smoking causes cancer essay

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How does smoking cause cancer?

• Smoking is the biggest cause of cancer in the UK, and worldwide.  
• Smoking damages the cells in our body and causes at least 15 different cancer types.  
• There is no safe level of smoking - s topping completely is the best thing you can do for your health, and there are tools and services to help you succeed.

What’s my cancer risk from smoking?

Smoking causes at least 15 different types of cancer and is the biggest cause of lung cancer in the UK. Smoking causes other diseases too, such as heart disease and various lung diseases.

If you smoke, stopping completely is the best thing you can do for your health.

Both the amount you smoke, and the length of time you’ve been smoking for, affect your cancer risk.

The more cigarettes you smoke a day, the higher your risk of cancer. So reducing the number of cigarettes you smoke a day is a good first step.

But the number of years you smoke for affects your cancer risk the most . So it’s important to make a plan to stop smoking completely.

The sooner you stop, the lower your risk of cancer. Everyone who smokes can benefit from stopping, and it’s never too late to stop - even if you’ve smoked for years. Speak to your doctor or pharmacist, free local stop smoking service, or visit NHS Smokefree to get support on how to stop smoking for good.

Find out more about how to stop smoking

What types of cancer does smoking cause?

The link between smoking and cancer is very clear. It causes at least 15 different types of cancer, including two of the most common types: lung cancer and bowel cancer.

Cancers caused by smoking include:

• nose and sinuses
• pharynx (upper throat)
• larynx (voice box)
• oesophagus (food pipe)
• some types of leukaemia

There is growing evidence that smoking also causes other types of cancer, including breast cancer. But we need more quality research to be able to say for certain that smoking causes breast cancer.

Smoking causes cancer in multiple ways. The main way is by damaging the DNA in our cells.

DNA controls how our cells grow and behave. Damage to DNA causes cells to behave in ways that they’re not supposed to. And the build-up of DNA damage over time can lead to cancer.

how_smoking_causes_cancer_v4_002.png

Cigarette smoke contains over 5000 chemicals and many of these are harmful - we know at least 70 can cause cancer.

When smoking, the harmful chemicals enter our lungs and affect the entire body.

These chemicals damage our DNA, including parts of our DNA that protect us against cancer.

Chemicals in cigarette smoke also make it harder for our cells to repair DNA damage. This means DNA damage can build up.

It’s the build-up of DNA damage in the same cell over time that leads to cancer.

You can find more information on the chemicals in cigarettes that cause cancer and what smoking does to the body on our webpage.

What causes lung cancer?

Smoking is the biggest cause of lung cancer. And lung cancer is the most common cause of cancer death.

Smoking causes more than 7 in 10 lung cancer cases in the UK. Both active smoking and passive smoking cause lung cancer. Passive smoking is when a person breathes in someone else’s tobacco smoke. You can find out more about passive smoking on our webpage.

There are some other things that increase your risk of lung cancer, which you can learn more about on our causes of lung cancer page.

People who smoke sometimes have a cough. But coughing can be a sign of lung cancer, as well as other health conditions.  If you have a persistent cough, breathlessness or any other symptom that’s new for you or won’t go away, it’s important that you tell your doctor about it. If you have any doubts, don’t ignore it.

Remember, it’s never too late to stop smoking and reduce your risk of lung cancer. The best way to reduce your risk is to stop smoking completely.

Our tips and support to help you stop smoking for good .

Does light, occasional and social smoking cause cancer?

Yes, ‘light’, ‘occasional’, or ‘social smoking’ still increases your risk of cancer.

Even smoking fewer cigarettes than 1 a day increases the risk of dying early, compared to people who have never smoked. And studies looking at people who smoke fewer than 10 cigarettes per day show an increased risk of smoking-related cancers and other diseases.

Reducing the number of cigarettes you smoke a day is a good first step. But, there is no safe level of smoking. The best thing you can do for your health is to stop smoking completely, and it is never too late to stop.

Key references

Brown, K. F. et al. The fraction of cancer attributable to modifiable risk factors in England, Wales, Scotland, Northern Ireland, and the United Kingdom in 2015. Br. J. Cancer. 118, 1130–1141 (2018).

Cancer Research UK. Lung cancer statistics. Cruk.org/health-professional/cancer-statistics/statistics-by-cancer-type/lung-cancer 

International Agency for Research on Cancer. Personal Habit and Indoor Combustion: Tobacco Smoking. 100 E, 377–504 (2012).

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• Published: 12 May 2017

Establishment of a Strong Link Between Smoking and Cancer Pathogenesis through DNA Methylation Analysis

• Yunlong Ma 1 , 2 &
• Ming D. Li 1 , 2 , 3  

Scientific Reports volume  7 , Article number:  1811 ( 2017 ) Cite this article

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• DNA methylation
• Risk factors

Smoking is a well-documented risk factor in various cancers, especially lung cancer. In the current study, we tested the hypothesis that abnormal DNAm loci associated with smoking are enriched in genes and pathways that convey a risk of cancer by determining whether smoking-related methylated genes led to enrichment in cancer-related pathways. We analyzed two sets of smoking-related methylated genes from 28 studies originating from blood and buccal samples. By analyzing 320 methylated genes from 26 studies on blood samples (N = 17,675), we found 57 enriched pathways associated with different types of cancer (FDR < 0.05). Of these, 11 were also significantly overrepresented in the 661 methylated genes from two studies of buccal samples (N = 1,002). We further found the aryl hydrocarbon receptor signaling pathway plays an important role in the initiation of smoking-attributable cancer. Finally, we constructed a subnetwork of genes important for smoking-attributable cancer from the 48 non-redundant genes in the 11 oncogenic pathways. Of these, genes such as DUSP4 and AKT3 are well documented as being involved in smoking-related lung cancer. In summary, our findings provide robust and systematic evidence in support of smoking’s impact on the epigenome, which may be an important contributor to cancer.

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Introduction.

Cigarette smoking is a common adverse behavior resulting in various cancers 1 . Notably, smoking confers a higher risk for lung cancer, on average between 5- and 10-fold. In developed countries, smoking is responsible for more than four of five cases of lung cancer 2 . A recent World Health Organization report 3 showed that smoking-related deaths worldwide are approximately 6 million annually, of which the main deadly cause is cancer.

More than 60 known carcinogens have been detected in cigarette smoke 4 , which include polycyclic aromatic hydrocarbons (PAHs), nitrosamines, and aromatic amines; all play a crucial role in tumorigenesis 5 . Nicotine per se not only is the main addictive compound causing smokers to continue to their habit but also makes a genotoxic contribution to the pathogenesis of cancer 6 . Most of these carcinogenic substances require metabolic activation to form DNA adducts that evoke genetic mutations and epigenetic reprogramming, which have been linked to genomic instability and other alterations 4 .

So far, many genetic association studies have revealed numerous variants underlying smoking-attributable cancers 7 , 8 , 9 . One of the most robust findings in genome-wide association studies is that variants in the CHRNA5 / A3 / B4 cluster on chromosome 15q24-25.1 show a significant association with both nicotine dependence and lung cancer 10 . However, current genetics-based evidence is lacking for elucidating the carcinogenic mechanisms of cigarette smoking-associated cancers, which leads many researchers to focus on the function of smoking-associated DNA methylation (SA-DNAm).

DNA methylation, a reversible and heritable alteration that attaches a methyl group to a nucleotide, influences the expression of a disease by mediating transcriptional regulation of genes 11 , alternative splicing 12 , or the integrity of the genome 13 . Recent studies have demonstrated an important role for changes in DNAm during the earlier stages of carcinogenesis 14 , 15 . Furthermore, multiple lines of evidence from candidate gene-specific methylation (GSM) studies 16 have indicated that aberrant DNAm in the promoter region of susceptibility genes for cigarette smoking confer a risk of cancer.

As high-throughput next-generational sequencing and array platforms emerge, our research approach and concept have been converted from hypothesis-driven exploration to data-driven hypothesis generation 17 . Many epigenome-wide association studies (EWASs) have revealed a greater number of DNAm loci associated significantly with in utero effects of either maternal smoking 18 or smoking in adulthood 19 . Besides, several studies have indicated that sustained exposure to cigarette smoke is an indicator of epigenetic reprogramming at a global level by measuring the methylation of repetitive elements, such as those of Sat2 20 and LINE-1 21 .

To the best of our knowledge, there has been no study that provides a systematic analysis of these identified SA-DNAm loci with the system biology approach for smoking behavior. Our working hypothesis was that abnormal DNAm loci associated with smoking are enriched in important genes and biological pathways, which convey a risk of the initiation and progression of cancer. The primary objective of this study was to test this hypothesis by determining whether these methylated genes in smokers are indeed enriched in well-documented biological pathways implicated in the etiology of cancer.

Genes enriched by SA-DNAm from blood samples

Following the procedure described in Supplementary Figure  S1 , 28 studies published between 2008 and 2015 were identified, which included 9 candidate GSM studies and 19 EWASs (N = 18,677 subjects; Supplementary Table  S1 ). Of them, 26 studies were from 17,675 blood samples. For the blood samples, 320 SA-DNAm-enriched genes with at least two independent pieces of evidence were included for the pathway-based analysis in the discovery stage. A list of the genes from the blood samples is shown in Supplementary Table  S2 .

Overrepresented pathways of genes from blood samples

In the discovery stage, we did pathway analysis of 320 genes significantly methylated by smoking, which revealed 90 overrepresented biological pathways with an FDR Q value of <0.05 (Supplementary Table  S4 ). Of these, 57 pathways were reported to be associated with the etiology of cancer (Supplementary Table  S5 ). For example, the most significant pathway of “MSP-RON signaling” (FDR Q value = 2.2 × 10 −4 ; see Table  1 ) has been implicated in regulating the activity of macrophages in response to inflammatory stimuli related to epithelial and leukemic carcinogenesis 22 . The second significant one, “RAR activation,” was overrepresented by 12 identified genes (FDR Q value = 3.7 × 10 −4 ) and has been prominently associated with the development of cancer 23 .

Furthermore, some of these overrepresented pathways cause vulnerability to a specific type of cancer (Supplementary Table  S5 ), such as the pathways of “non-small cell lung cancer signaling” (FDR Q value = 9.6 × 10 −3 ), “small cell lung cancer signaling” (FDR Q value = 0.012), “pancreatic adenocarcinoma signaling” (FDR Q value = 0.017), “renal cell carcinoma signaling” (FDR Q value = 0.026), “ovarian cancer signaling” (FDR Q value = 0.026), and “prostate cancer signaling” (FDR Q value = 0.041). In addition, many other overrepresented pathways are involved in the oncogenic process of various cancers, which include “actin cytoskeleton signaling” (FDR Q value = 7.1 × 10 −4 ), “signaling by rho family GTPases” (FDR Q value = 1.5 × 10 −3 ), “AMPK signalling” (FDR Q value = 1.6 × 10 −3 ), and “ERK/MAPK signaling” (FDR Q value = 5.8 × 10 −3 ) (Supplementary Table  S5 ).

Common molecular pathways in blood and buccal samples

To validate the findings from blood samples, we conducted a similar pathway-based analysis for significantly methylated genes from the buccal samples, which revealed 32 common pathways in the two kinds of samples (P < 0.05; Supplementary Table  S6 ). Among them, 11 pathways were associated with cancer (Table  2 ), including “RAR activation,” “actin cytoskeleton signaling,” “aryl hydrocarbon receptor signaling,” “signaling by rho family GTPases,” and “molecular mechanisms of cancer.” This provides evidence that these pathways are highly likely to contribute to the pathogenesis of smoking-attributable cancer.

Interestingly, various crucial cancer-related genes, such as AHRR , CYP1A1 , TNF , SMARCA4 , CDK6 , RARA , RXRB , CDKN1A , RARG , and NFE2L2 , were enriched in the “aryl hydrocarbon receptor signaling pathway” (Supplementary Table  S5 ), through which abnormal epigenetic programming may trigger smoking-attributable cancer (Fig.  1 ). Figure  2 presents a schematic model of major oncogenic pathways underlying the molecular mechanism of smoking-attributable cancer.

The pathway of “aryl hydrocarbon receptor signaling”-initiated smoking-related cancer. Arrows show event flow. –m represents hypomethylation, and +m represents hypermethylation. The plot was generated using Microsoft PowerPoint. Under normal circumstances, toxic substances from cigarette smoke, including PAHs, nitrosamines, and aromatic amines, could enter the bloodstream through the alveolar capillary system and be taken up by pulmonary cells. Toxic chemicals such as the PAHs bind to transcription factor AhR, which results from the dissociation of AhR and an associated chaperone protein (Chap) complex. After translocating to the nucleus, PAHs and AhR dissociate, and AhR is dimerized with ARNT, which is produced from the AhRR–ARNT complex. The resulting complex binds to the XRE in the promoter of CYP1A1 to enhance the expression of CYP1A1. The CYP1A1 then metabolizes PAHs into hydrophilic intermediates such as B[a]-7,8-dihydrodiol-9,10-epoxide (BPDE), which can be detoxified through the glutathione S-transferase (GST) family of enzymes or, in an alternative manner, form DNA adducts. Under abnormal circumstances, CYP1A1 is -m or AhRR has altered methylation (−m or +m) that may extraordinarily enhance the expression of CYP1A1, which could induce more DNA adduct formation that results in miscoding of the DNA sequence. Under long-term smoking exposure, the DNA sequence suffers persistent miscoding that triggers epigenetic changes in many critical cancer genes, such as NOTCH1 , ATK3 , DUSP4 , SMAD6 , and SMARCA4 .

Schematic representation of the major enriched pathways underlying smoking-attributable cancers. Accumulating evidence indicates that smoking prominently induces cancer development. Based on the DNAm-enriched genes associated with smoking, we identified various overrepresented pathways. The major pathways were then linked on the basis of their biological relations originating from the database of IPA and reported literature. The dashed line representing the link between two pathways was reviewed from the reported literature. The plot is generated using Microsoft PowerPoint.

Similar to pathway analysis, we did a GO analysis for those significantly methylated genes from both blood and buccal samples. In the blood sample, we found 19 enriched categories of molecular functions, with an FDR Q value < 0.05 (Supplementary Table  S7 ). The most significantly enriched gene set was “transcription activator activity,” with an enrichment of 3.22 (FDR Q value = 1.92 × 10 −4 ). The second most significant one was “sequence-specific DNA binding,” with an enrichment of 2.73 (FDR Q value = 1.92 × 10 −4 ). Seven categories of molecular functions were detected in the buccal samples as well (Table  3 ).

To gain insights from the pathological viewpoint, we did disease-focused enrichment analysis on those genes significantly methylated by smoking in both blood and buccal cells. The most significantly enriched disease was cancer (Supplementary Figure  S2 ). This again indicates that many of these genes methylated by smoking are indeed correlated with cancer.

Subnetwork constructed from the 11 common cancer-related pathways

Considering the presence of a significant number of overlapping genes among the 11 common pathways, we selected 48 non-redundant genes based on their biological functions and appearance frequencies among the common pathways and used them to construct a cancer-associated molecular subnetwork (Fig.  3 ). The well-documented cancer-related genes NOTCH1 , CDKN1A , EGR1 , AKT3 , TNF , MMP9 , and SMARCA4 are located in the center of this newly constructed subnetwork (Fig.  3 ).

Gene subnetwork constituted by genes from the 11 common oncogenic pathways. The protein–protein interactions were based on the database of STRING v 10.0. We used Cytoscape software to visualize the subnetwork. The color of a node indicates the methylation direction of CpG loci in a gene. Red = hypermethylation, green = hypomethylation, and yellow = both hyper- and hypomethylation at different sites. The edges of the genes represent predicted functional links. The number of edges in each gene was used for determining the node size, of which NOTCH1 is the biggest.

48 smoking-related methylated genes contribute to lung cancer

To gain further evidence of the contribution of the 48 methylated genes to cancer, we investigated the relation between RNA expression and methylation for the genes in the TCGA dataset. Among these genes, we found 148 methylation sites in different regions, with the largest number located in the gene body and 5′UTR (Fig.  4a ). After examining the correlation between methylation loci and RNA expression in lung adenocarcinoma (LUAD) and lung squamous-cell carcinoma (LUSC) samples, we found that large portions of the methylation loci were significantly positively or negatively correlated with RNA expression in both LUAD (Fig.  4b and Supplementary Tables  S8 and S9 ) and LUSC (Fig.  4c and Supplementary Tables  S10 and S11 ). Most of the methylation loci correlated with RNA expression were located in the gene body and 5′-UTR in both LUAD (Supplementary Figure  S3a,b ) and LUSC (Supplementary Figure  S3c,d ).

Methylation loci of the 48 identified genes. ( a ) Proportion of methylation loci in different regions. ( b ) Proportion of methylation loci that showed no, positive, or negative correlation with RNA expression in LUAD samples. ( c ) Proportion of methylation loci that showed no, positive, or negative correlation with RNA expression in LUSC samples. ( d ) Venn diagram shows that many methylation loci correlate consistently with the degree of expression of the associated gene in both LUAD and LUSC.

Interestingly, the majority of methylation loci correlated with the expression of the associated genes in both the LUAD and LUSC samples showed consistent directions (Fig.  4d ). There were 18 methylation probes showing a positive correlation with RNA expression in both LUAD (51.4%) and LUSC (69.2%), and 25 methylation probes showing negative correlation with RNA expression in both LUAD (58.1%) and LUSC (67.6%). For example, the cg07151117 probe located in the 5′-UTR of DUSP4 , the cg27514333 probe located in the gene body of SMAD6 , and the cg26271591 probe located in the 5′-UTR of NFE2L2 correlated in a significantly negatively way with RNA expression in both LUAD (Table  4 , Fig.  5a,b , and Supplementary Figure  S4a,b ) and LUSC (Table  4 and Supplementary Figures  S5a,b and S6a,b ), and the cg11314684 probe in the gene body of AKT3 , the cg02385153 probe in the gene body of AHRR , and the cg24538512 probe in the gene body of NFATC1 were significantly positively correlated with RNA expression in both LUAD (Table  4 and Supplementary Figure  S4c,d ) and LUSC (Table  4 and Supplementary Figure  S5c,d ).

Two methylation probes of DUSP4 in LUAD samples. ( a ) Correlation of cg07151117 probe with RNA expression in control and cancer cells. ( b ) Correlation of cg24379915 probe with RNA expression in control and cancer cells. ( c ) Extent of methylation of cg07151117 probe in control and cancer cells. ( d ) Extent of methylation of cg24379915 probe in control and cancer cells. P value was calculated by the Wilcoxon-rank sum test.

On the other hand, we found that most of the methylation loci that correlated with RNA expression were significantly differentially expressed in the control tissues vs. cancer in both LUAD and LUSC samples (Supplementary Table  S12 and Supplementary Figures  S7 and S8 ). This is especially true for DUSP4 . There were two methylation probes (cg07151117 and cg24379915) of this gene showing significant correlation with RNA expression in both LUAD (Table  4 and Fig.  5a,b ) and LUSC (Table  4 and Supplementary Figure  S6a,b ). The cg07151117 probe showed the strongest inverse correlation between methylation and expression in LUAD samples (r = −0.742; P < 0.001; see Table  4 and Fig.  5a ). The cg24379915 probe was negatively correlated with DUSP4 expression in the LUAD samples (r = −0.657; P < 0.001; see Table  4 and Fig.  5b ). Compared with normal tissues, there were two hypomethylation probes of DUSP4 in cancer tissues (Fig.  5c,d and Supplementary Figure  S6c,d ). Consistently, the associations of smoking with the two methylation probes of DUSP4 in LUAD samples (Fig.  6a and b ) were in line with the finding that these two CpG loci of DUSP4 tended to be hypomethylated in smokers, as found by previous EWASs 24 , 25 .

Associations between smoking and methylation of DUSP4 in LUAD samples. ( a ) Methylation probe of cg07151117. ( b ) Methylation probe of cg24379915. *P < 0.05, **P < 0.01, and ***P < 0.001.

In recent years, many studies have emphasized the association of current smoking with DNAm, which is considered a critical mediating factor in the pathogenesis of cancer. In light of epidemiologic evidence indicating that cigarette smoking is highly correlated with cancer, we performed a systematic bioinformatics analysis with the goal of revealing the underlying mechanism of smoking-attributable cancer from an epigenetic point of view, which revealed a group of genes and pathways implicated in the pathology of interest. Based on the findings from the current study and previous biological evidence, we present a schematic model for elucidating the biological effects of smoking on cancer pathogenesis (Fig.  2 ).

There are two types of studies used to discern the association between smoking and DNAm: candidate GSM and EWAS. For candidate GSM studies, only a limited number of CpG sites mapped to a candidate gene of interest can be investigated. In contrast, a significant number of CpG sites can be studied with EWASs 24 , 25 , 26 . Although EWAS is powerful for identifying novel methylated CpG sites, many confounding factors remain unresolved. For example, in light of the tens of thousands of CpG sites that could be analyzed simultaneously in an EWAS, a significant proportion of reported studies might not have had a large enough sample to decrease the rate of false-positive associations evoked by multiple testing. Further, the presence of epigenetic and genetic heterogeneity and multiple interacting genes can limit the identification of the underlying molecular mechanism of complex diseases. Thus, pathway-based analysis is useful not only for reducing the influence of false-positive findings but also to collaborate the reported genes statistically based on particular biological functions to uncover the meaningful networks conveying the risk of smoking-induced cancer. In the current study, although we used three bioinformatics tools (i.e., IPA, EnrichNet, and GeneTrail) based on different databases to conduct the pathway-based analysis, the main findings were generated by the IPA.

Two independent SA-DNAm-enriched gene sets were extracted from blood and buccal samples. Among the genes from blood samples, many have strong association signals with smoking with multiple replications, such as AHRR , F2RL3 , AKT3 , and GFI1 . For example, AHRR , a tumor suppressor gene on chromosome 5p15.33, encodes a class E basic helix–loop–helix protein that dampens the translocation of AHR–ligand complex to the nucleus. Knockdown of AHRR is correlated with greater tumor cell invasiveness in many tissues, including those of the lung, colon, ovary, and breast 27 . The F2RL3 protein is related to platelet activation and coagulation, as well as to cell signaling. Epigenetic association studies 28 , 29 have provided consistent evidence that F2RL3 methylation predisposes to implicatation in lung or colon cancer. By performing a genome-wide methylation analysis, Fasanelli et al . 30 demonstrated that smoking-induced hypomethylation in AHRR and F2RL3 contributes to the risk of lung cancer, providing evidence of specific altered methylation that can mediate the effect of smoking on cancer pathogenesis. Very recently, Joehanes et al . 31 conducted a meta-analysis of genome-wide DNA methylation for the effect of smoking on DNA methylation based on 15,907 blood-derived DNA samples from subjects in 16 cohorts. By comparing current smokers (N = 2,433) with never smokers (N = 6,956), 18,760 CpG sites annotated to 7,201 genes were found to be differentially methylated at a genome-wide false discovery rate (FDR) <0.05. Although these results replicated many previously reported loci, including CpGs annotated to AHRR , RARA , and F2RL3 , the authors did not use an independent sample to replicate most of the identified CpG loci. By performing an enrichment analysis for smoking-related phenotypes in the NHGRI-EBI GWAS Catalog, these authors found that these smoking-related methylated genes were significantly overrepresented in all types of cancer (P = 8.0 × 10 −15 ), lung adenocarcinoma (P = 1.5 × 10 −3 ), and colorectal cancer (P = 1.4 × 10 −3 ), which is in line with our findings. In comparison, we found that 95.6% (306/320) of the genes identified in blood samples and 68.7% (454/661) of those in buccal samples overlapped with the genes (N = 7,201) of Joehanes’ study, which offers supportive evidence of the importance of the smoking-related methylated genes used in current study.

By employing a systematic statistical analysis, several intriguing findings emerged from our analyses, which probably never would have been identified in any individual epigenetic association study, including EWAS. Our analysis of methylated genes from blood corroborated the view that many oncogenic pathways were significantly associated with smoking, including non-small-cell lung cancer signaling, small-cell lung cancer signaling, prostate cancer signaling, and renal-cell carcinoma signaling. Furthermore, many other enriched pathways, for example MSP-RON signaling, RAR activation, rac signaling, and actin cytoskeleton signaling, which have been associated with the etiology of cancer in previous studies (Supplementary Table  S5 ), were remarkably linked with smoking. For instance, the retinoic acid receptors (RARs) have potent anti-proliferative and anti-inflammatory properties, suppressing the activity of transcription factors AP-1 and NF-κB. Our findings thus suggest that abnormalities in the pathway of “RAR activation” confer susceptibility to cancer. Recently, Guilhamon et al . 32 reported that the “RAR activation” pathway is affected by differential methylation in cancers.

To confirm our findings using blood samples, we conducted an independent pathway-based analysis of methylated genes from buccal cells, which validated 11 cancer-related pathways. This confirmation indicates that these common oncogenic pathways play important roles in the pathology of smoking-attributable cancer. Particularly, the pathway of aryl hydrocarbon receptor signaling plays a crucial role in detoxification of the toxic components of cigarette smoke, including PAHs, nitrosamines, and aromatic amines 33 . If there were aberrant modifications in this biological regulation, these toxic substances could directly influence the epigenetic profile of circulating whole blood cells or other tissues. Using mice lacking the aryl hydrocarbon receptor (AhR), several studies 34 have shown that AhR regulates angiogenesis by activating vascular endothelial growth factor in the endothelium and inactivating tumor growth factor-β in the stroma; both are important in supporting the proliferation of tumor cells by supplying nutrients and oxygen. Together, abnormal smoking-related DNAm in the aryl hydrocarbon receptor signaling pathway may induce more DNA adduct formation that leads to miscoding of the sequence of DNA (see Fig.  1 ). With long-term smoking exposure, the DNA sequence suffers persistent miscoding that triggers epigenetic changes in various vital oncogenes, such as NOTCH1 , ATK3 , DUSP4 , SMAD6 , and S MARCA4 , in the major enriched pathways (see Fig.  2 ) and leads to carcinogenesis, indicating that the aryl hydrocarbon receptor signaling pathway probably is implicated in the initiation of smoking-induced cancers.

Because pathway-based analysis cannot identify genes that work across different pathways, network analysis has been widely used to search for groups of functionally related genes that may collectively convey susceptibility to diseases such as cancer. In addition, because abnormal methylation may be implicated in cancer development through regulation of gene expression, we explored whether the smoking-associated methylation loci were correlated with RNA expression of genes identified in LUAD and LUSC. Thus, by using the web-based tool STRING 35 , we offer a subnetwork for the 48 non-redundant genes among the 11 common oncogenic pathways. Of note, 47 of the 48 genes (97.9%) in the subnetwork overlapped with the genes mapped by smoking-related CpG loci at a genome-wide FDR < 0.05 in Joehanes’s study 31 . Many of the 48 genes play essential roles and have been implicated in a variety of cancers. For example, the hub gene of NOTCH1 , encoding one of the four Notch receptors, has an important role in a signaling pathway that is involved in multifaceted regulation of cell survival, proliferation, tumor angiogenesis, and metastasis 36 . A substantial body of research shows that NOTCH1 is correlated with the pathology of cancer 37 . By cross-talking with many other critical cancer genes and pathways, NOTCH1 plays a fundamental role in cancer pathogenesis. Aberrant methylation of NOTCH1 may thus lead to a greater risk of smoking-induced cancer. Besides, the SWI/ShNF chromatin-remodeling complex, which has been linked to lung, pancreas, breast, and colon cancer 38 , is comprised of a catalytic subunit of either SMARCA4 or SMARCA2 . The product of SMARCA4 modulates gene expression by using the energy of ATP hydrolysis to modify chromatin structure. Both DNA mutation and methylation influence the expression of SMARCA4 in cancers such as Burkitt lymphoma 39 , ovarian carcinoma 40 , and lung cancer 41 . Consistently, two methylation loci (cg18040892 and cg23963476) were significantly inversely correlated with RNA expression of SMARCA4 in LUSC samples. The extent of methylation of the cg23963476 probe, which is hypomethylated in smokers 25 , was significantly lower in LUSC tissues than in control tissues, suggesting that smoking-associated hypomethylation of SMARCA4 elicits the development of lung cancer.

Furthermore, the DUSP4 gene, which interacts with the hub genes TNF and EGR1 , plays an important role in the subnetwork of 48 genes involved in oncogenesis. DUSP4 , which belongs to dual-specificity phosphatase (DUSPs) family, regulating the activity and location of MAPKs, is a negative regulator of extracellular-regulated kinase activity and is upregulated in EGFR-mutant lung cancer cell lines compared with K-ras-mutant cells 42 . Coincidently, a group of investigators reported that allelic loss of DUSP4 led to underexpression of DUSP4 in EGFR-mutant lung adenocarcinoma 43 . In addition, numerous studies have shown that DUSP4 acts as a tumor suppressor 44 , 45 or promotes cancer progression 46 , 47 depending on cancer type. In the present study, we found that two smoking-associated methylation probes (cg07151117 and cg24379915) that are correlated with RNA expression of DUSP4 were significantly hypomethylated in both LUAD and LUSC cancer tissues compared with the control samples. These results indicate that hypomethylated DUSP4 is involved in smoking-induced lung cancer. Together, our proposed subnetwork of 48 genes is not only enriched for genes associated with cancer but also associates with smoking-attributable cancer.

There are several limitations to the present study. First, a number of human genes are uncharacterized or not mapped to manually curated or computationally predicated pathways. Therefore, the effects of these unique genes cannot be delineated in our pathway-based analysis. Second, smoking-associated or methylation-associated confounding factors, such as alcohol consumption and body mass index, which were not adjusted for in many of the studies we included, may contribute to the heterogeneity. Third, 661 genes were collected from two buccal-based studies with 1,002 subjects, whereas 320 genes were extracted from 26 blood-based studies with a much larger number of 17,675 subjects. This might imply that there were more false-positive methylated genes in buccal-based studies than in blood-based studies. Thus, we used the methylated genes from blood samples more extensively for pathway-based analysis and used the methylated genes from buccal samples only for replication. Finally, because of the limitation of the cross-sectional design-based study, which was adopted by all the studies we examined, we could not determine whether changes in DNAm were direct consequences of smoking or part of its pathology.

In sum, the present study marks one of the first comprehensive pathway-based analyses of the abnormal methylation of DNA in adult smokers. Our findings indicate strongly that cigarette smoking causes prominent alterations in DNAm enriched in numerous genes and biologically meaningful pathways implicated in cancer pathology. This provides strongly and holistically epigenetics-based evidence in support of the carcinogenic effect of smoking on cancer. However, our understanding of the contribution of smoking-related DNAm to cancer pathogenesis is still in an early stage. More studies are warranted to reveal the specific function of aberrant methylation of particular genes in response to smoking in the development of cancer. Such understanding will have clinical implications for the personalized treatment of smoking-attributable cancer.

To identify all studies on the association of cigarette smoking with alterations in DNAm, a total of 1,447 studies published prior to June 13, 2015, were retrieved from the PubMed database. The key words used for the search were “smoking,” “smoke,” “tobacco,” “nicotine,” “cigarette,” and “methylation.” All abstracts of these reports were reviewed for potentially eligible papers. We also manually checked the references individually for additional studies not indexed by the PubMed database.

To eliminate or minimize false-positive findings, we narrowed our selection criteria by choosing genes with significant reported associations with smoking. Once a paper met the inclusion criteria, the full text of the article was reviewed to ensure the conclusion was in accordance with the content. After rigorous and systematic screening, 28 epigenetic association studies consisting of 9 candidate GSM studies and 19 EWASs were included, among which 26 studies were conducted on DNA extracted from whole blood and 2 on DNA from buccal cells (Supplementary Table  S1 ).

At first, we used the genes from the blood samples (Supplementary Table  S2 ) to discover the underlying pathways associated with cigarette smoking. To enhance the reliability of our study, we included only those genes whose relevance is supported by at least two independent pieces of evidence (i.e., there are two or more significant CpG loci within a gene or there is only one significant methylation locus in a gene but the finding has been replicated in two or more independent samples). Under the same inclusion criteria, we also extracted an independent list of genes from buccal cells (Supplementary Table  S3 ) to validate the pathways identified from the blood samples.

Identification and validation of enriched biological pathways

To obtain a comprehensive understanding of the influence of smoking on cancer from an epigenetic perspective, we conducted stepwise pathway-based analyses for the two types of samples using the bioinformatics tools of Ingenuity Pathway Analysis (IPA) 48 , EnrichNet 49 , and Genetrail 50 .

For IPA, the core part is the Ingenuity Pathways Knowledge Base (IPKB), which is a well-organized proprietary database consisting of extensive information on the functions or interactions of each gene or protein. Based on defined biological knowledge, IPA can analyze a user-defined set of genes for molecular functions, canonical pathways, or cellular networks. With the IPA application, the significance of each identified pathway is calculated as follows: (1) the number of input genes mapped to a given pathway in the IPKB database, denoted by m ; (2) the number of genes included in the pathway, denoted by M ; (3) the total number of input genes mapped to the IPKB database, denoted by n ; and (4) the total number of known genes included in the IPKB database, denoted by N . The significance of gene enrichment in the canonical pathways then is calculated using a one-tailed Fisher’s exact test 51 . A P value of <0.05 indicates a statistically significant link between the gene and a given pathway. Nevertheless, because many canonical pathways are examined simultaneously, we used the method of Benjamini-Hochberg 52 to correct for multiple testing.

Two other web-based bioinformatics tools (i.e., EnrichNet and GeneTrail) for pathway analysis depend on popular public databases, such as the Kyoto Encyclopedia of Genes and Genomes (KEGG) 53 , Wiki pathways 54 , and Biocarta pathway 55 . By using overrepresentation analysis, these tools could be applied for identification, prioritization, and analysis of functional associations between user-collected gene sets and specified canonical pathways. Furthermore, we used the Biological Networks Gene Ontology tool (BiNGO; v 2.44) 56 for Gene Ontology (GO) analysis, where GO terms are significantly overrepresented in a set of genes calculated by the hypergeometric test 57 (FDR Q value < 0.05). ReViGO with default parameters 58 was used to remove the redundant GO terms according to the enrichment in molecular functions. After obtaining the common pathways from both blood and buccal samples, we selected the non-redundant genes among the pathways to construct a cancer-associated molecular subnetwork based on the database of STRING v 10.0 35 . We used the software of Cytoscape 59 to visualize the cancer-associated molecular subnetwork.

We also downloaded level 3 DNA methylation data (i.e., JHC_USC HumanMethylation450K) 60 , 61 and level 3 RNA expression data (i.e., UNC IlluminaHiSeq_RNASeqV2) 60 , 61 on lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) from the large-scale database of TCGA 62 to provide validation for the identified smoking-related oncogenes. The RNA expression data are log-transformed before being utilized for statistical analysis and data visualization. By using the web-based tool of MEXPRESS 63 , which has two main functions of Pearson correlation 64 and the non-parametric Wilcoxon rank-sum test 65 , we determined whether methylation probes were correlated with the extent of expression of the associated genes in both LUAD and LUSC samples and the different status of methylation loci correlated with RNA expression between control and cancer in LUAD or LUSC samples. The R packages ( http://www.r-project.org/ ), such as VennDiagram 66 and ggplot2 67 were utilized for other statistical analyses and data visualization. By using multiple bioinformatics tools based on different databases, we were able to identify the important genes and biologically meaningful pathways contributing to the vulnerability to smoking-attributable cancer.

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Acknowledgements

We thank Dr. David L. Bronson for excellent editing of this manuscript. This study was supported in part by the China Precision Medicine Initiative (2016YFC0906300), the Research Center for Air Pollution and Health of Zhejiang University, the Ministry of Science and Technology of China (2012 AA020405), and U.S. National Institutes of Health grant DA012844.

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Y.M. performed data collection and analysis and wrote the manuscript. M.D.L. conceived the study and helped write the manuscript.

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Ma, Y., Li, M.D. Establishment of a Strong Link Between Smoking and Cancer Pathogenesis through DNA Methylation Analysis. Sci Rep 7 , 1811 (2017). https://doi.org/10.1038/s41598-017-01856-4

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Harms of Cigarette Smoking and Health Benefits of Quitting

What harmful chemicals does tobacco smoke contain.

Tobacco smoke contains many chemicals that are harmful to both smokers and nonsmokers. Breathing even a little tobacco smoke can be harmful ( 1 - 4 ).

Of the more than 7,000 chemicals in tobacco smoke, at least 250 are known to be harmful, including hydrogen cyanide , carbon monoxide , and ammonia ( 1 , 2 , 5 ).

Among the 250 known harmful chemicals in tobacco smoke, at least 69 can cause cancer. These cancer-causing chemicals include the following ( 1 , 2 , 5 ):

• Acetaldehyde
• Aromatic amines
• Beryllium (a toxic metal)
• 1,3–Butadiene (a hazardous gas)
• Cadmium (a toxic metal)
• Chromium (a metallic element)
• Ethylene oxide
• Formaldehyde
• Nickel (a metallic element)
• Polonium-210 (a radioactive chemical element)
• Polycyclic aromatic hydrocarbons (PAHs)
• Tobacco-specific nitrosamines
• Vinyl chloride

What are some of the health problems caused by cigarette smoking?

Smoking is the leading cause of premature, preventable death in this country. Cigarette smoking and exposure to tobacco smoke cause about 480,000 premature deaths each year in the United States ( 1 ). Of those premature deaths, about 36% are from cancer, 39% are from heart disease and stroke , and 24% are from lung disease ( 1 ). Mortality rates among smokers are about three times higher than among people who have never smoked ( 6 , 7 ).

Smoking harms nearly every bodily organ and organ system in the body and diminishes a person’s overall health. Smoking causes cancers of the lung, esophagus, larynx, mouth, throat, kidney, bladder, liver, pancreas, stomach, cervix, colon, and rectum, as well as acute myeloid leukemia ( 1 – 3 ).

Smoking also causes heart disease, stroke, aortic aneurysm (a balloon-like bulge in an artery in the chest), chronic obstructive pulmonary disease (COPD) ( chronic bronchitis and emphysema ), diabetes , osteoporosis , rheumatoid arthritis, age-related macular degeneration , and cataracts , and worsens asthma symptoms in adults. Smokers are at higher risk of developing pneumonia , tuberculosis , and other airway infections ( 1 – 3 ). In addition, smoking causes inflammation and impairs immune function ( 1 ).

Since the 1960s, a smoker’s risk of developing lung cancer or COPD has actually increased compared with nonsmokers, even though the number of cigarettes consumed per smoker has decreased ( 1 ). There have also been changes over time in the type of lung cancer smokers develop – a decline in squamous cell carcinomas but a dramatic increase in adenocarcinomas . Both of these shifts may be due to changes in cigarette design and composition, in how tobacco leaves are cured, and in how deeply smokers inhale cigarette smoke and the toxicants it contains ( 1 , 8 ).

Smoking makes it harder for a woman to get pregnant. A pregnant smoker is at higher risk of miscarriage, having an ectopic pregnancy , having her baby born too early and with an abnormally low birth weight, and having her baby born with a cleft lip and/or cleft palate ( 1 ). A woman who smokes during or after pregnancy increases her infant’s risk of death from Sudden Infant Death Syndrome (SIDS) ( 2 , 3 ). Men who smoke are at greater risk of erectile dysfunction ( 1 , 9 ).

The longer a smoker’s duration of smoking, the greater their likelihood of experiencing harm from smoking, including earlier death ( 7 ). But regardless of their age, smokers can substantially reduce their risk of disease, including cancer, by quitting.

What are the risks of tobacco smoke to nonsmokers?

Secondhand smoke (also called environmental tobacco smoke, involuntary smoking, and passive smoking) is the combination of “sidestream” smoke (the smoke given off by a burning tobacco product) and “mainstream” smoke (the smoke exhaled by a smoker) ( 4 , 5 , 10 , 11 ).

The U.S. Environmental Protection Agency, the U.S. National Toxicology Program, the U.S. Surgeon General, and the International Agency for Research on Cancer have classified secondhand smoke as a known human carcinogen (cancer-causing agent) ( 5 , 11 , 12 ). Inhaling secondhand smoke causes lung cancer in nonsmoking adults ( 1 , 2 , 4 ). Approximately 7,300 lung cancer deaths occur each year among adult nonsmokers in the United States as a result of exposure to secondhand smoke ( 1 ). The U.S. Surgeon General estimates that living with a smoker increases a nonsmoker’s chances of developing lung cancer by 20 to 30% ( 4 ).

Secondhand smoke causes disease and premature death in nonsmoking adults and children ( 2 , 4 ). Exposure to secondhand smoke irritates the airways and has immediate harmful effects on a person’s heart and blood vessels. It increases the risk of heart disease by an estimated 25 to 30% ( 4 ). In the United States, exposure to secondhand smoke is estimated to cause about 34,000 deaths from heart disease each year ( 1 ). Exposure to secondhand smoke also increases the risk of stroke by 20 to 30% ( 1 ). Pregnant women exposed to secondhand smoke are at increased risk of having a baby with a small reduction in birth weight ( 1 ).        

Children exposed to secondhand smoke are at an increased risk of SIDS, ear infections, colds, pneumonia, and bronchitis. Secondhand smoke exposure can also increase the frequency and severity of asthma symptoms among children who have asthma. Being exposed to secondhand smoke slows the growth of children’s lungs and can cause them to cough, wheeze, and feel breathless ( 2 , 4 ).

Is smoking addictive?

Smoking is highly addictive. Nicotine is the drug primarily responsible for a person’s addiction to tobacco products, including cigarettes. The addiction to cigarettes and other tobacco products that nicotine causes is similar to the addiction produced by using drugs such as heroin and cocaine ( 13 ). Nicotine is present naturally in the tobacco plant. But tobacco companies intentionally design cigarettes to have enough nicotine to create and sustain addiction. 

The amount of nicotine that gets into the body is determined by the way a person smokes a tobacco product and by the nicotine content and design of the product. Nicotine is absorbed into the bloodstream through the lining of the mouth and the lungs and travels to the brain in a matter of seconds. Taking more frequent and deeper puffs of tobacco smoke increases the amount of nicotine absorbed by the body.

Are other tobacco products, such as smokeless tobacco or pipe tobacco, harmful and addictive?

Yes. All forms of tobacco are harmful and addictive ( 4 , 11 ). There is no safe tobacco product.

In addition to cigarettes, other forms of tobacco include smokeless tobacco , cigars , pipes , hookahs (waterpipes), bidis , and kreteks . 

• Smokeless tobacco : Smokeless tobacco is a type of tobacco that is not burned. It includes chewing tobacco , oral tobacco, spit or spitting tobacco, dip, chew, snus, dissolvable tobacco, and snuff. Smokeless tobacco causes oral (mouth, tongue, cheek and gum), esophageal, and pancreatic cancers and may also cause gum and heart disease ( 11 , 14 ).
• Cigars : These include premium cigars, little filtered cigars (LFCs), and cigarillos. LFCs resemble cigarettes, but both LFCs and cigarillos may have added flavors to increase appeal to youth and young adults ( 15 , 16 ). Most cigars are composed primarily of a single type of tobacco (air-cured and fermented), and have a tobacco leaf wrapper. Studies have found that cigar smoke contains higher levels of toxic chemicals than cigarette smoke, although unlike cigarette smoke, cigar smoke is often not inhaled ( 11 ). Cigar smoking causes cancer of the oral cavity, larynx, esophagus, and lung. It may also cause cancer of the pancreas. Moreover, daily cigar smokers, particularly those who inhale, are at increased risk for developing heart disease and other types of lung disease.
• Pipes : In pipe smoking, the tobacco is placed in a bowl that is connected to a stem with a mouthpiece at the other end. The smoke is usually not inhaled. Pipe smoking causes lung cancer and increases the risk of cancers of the mouth, throat, larynx, and esophagus ( 11 , 17 , 18 ).
• Hookah or waterpipe (other names include argileh, ghelyoon, hubble bubble, shisha, boory, goza, and narghile): A hookah is a device used to smoke tobacco (often heavily flavored) by passing the smoke through a partially filled water bowl before being inhaled by the smoker. Although some people think hookah smoking is less harmful and addictive than cigarette smoking ( 19 ), research shows that hookah smoke is at least as toxic as cigarette smoke ( 20 – 22 ).
• Bidis : A bidi is a flavored cigarette made by rolling tobacco in a dried leaf from the tendu tree, which is native to India. Bidi use is associated with heart attacks and cancers of the mouth, throat, larynx, esophagus, and lung ( 11 , 23 ).
• Kreteks : A kretek is a cigarette made with a mixture of tobacco and cloves. Smoking kreteks is associated with lung cancer and other lung diseases ( 11 , 23 ).

Is it harmful to smoke just a few cigarettes a day?

There is no safe level of smoking. Smoking even just one cigarette per day over a lifetime can cause smoking-related cancers (lung, bladder, and pancreas) and premature death ( 24 , 25 ).

What are the immediate health benefits of quitting smoking?

The immediate health benefits of quitting smoking are substantial:

• Heart rate and blood pressure , which are abnormally high while smoking, begin to return to normal.
• Within a few hours, the level of carbon monoxide in the blood begins to decline. (Carbon monoxide reduces the blood’s ability to carry oxygen.)
• Within a few weeks, people who quit smoking have improved circulation, produce less phlegm , and don’t cough or wheeze as often.
• Within several months of quitting, people can expect substantial improvements in lung function ( 26 ).
• Within a few years of quitting, people will have lower risks of cancer, heart disease, and other chronic diseases than if they had continued to smoke.

What are the long-term health benefits of quitting smoking?

Quitting smoking reduces the risk of cancer and many other diseases, such as heart disease and COPD , caused by smoking.

Data from the U.S. National Health Interview Survey show that people who quit smoking, regardless of their age, are less likely to die from smoking-related illness than those who continue to smoke. Smokers who quit before age 40 reduce their chance of dying prematurely from smoking-related diseases by about 90%, and those who quit by age 45-54 reduce their chance of dying prematurely by about two-thirds ( 6 ).

Regardless of their age, people who quit smoking have substantial gains in life expectancy, compared with those who continue to smoke. Data from the U.S. National Health Interview Survey also show that those who quit between the ages of 25 and 34 years live about 10 years longer; those who quit between ages 35 and 44 live about 9 years longer; those who quit between ages 45 and 54 live about 6 years longer; and those who quit between ages 55 and 64 live about 4 years longer ( 6 ).

Also, a study that followed a large group of people age 70 and older ( 7 ) found that even smokers who quit smoking in their 60s had a lower risk of mortality during follow-up than smokers who continued smoking.

Does quitting smoking lower the risk of getting and dying from cancer?

Yes. Quitting smoking reduces the risk of developing and dying from cancer and other diseases caused by smoking. Although it is never too late to benefit from quitting, the benefit is greatest among those who quit at a younger age ( 3 ).

The risk of premature death and the chances of developing and dying from a smoking-related cancer depend on many factors, including the number of years a person has smoked, the number of cigarettes smoked per day, and the age at which the person began smoking.

Is it important for someone diagnosed with cancer to quit smoking?

Quitting smoking improves the prognosis of cancer patients. For patients with some cancers, quitting smoking at the time of diagnosis may reduce the risk of dying by 30% to 40% ( 1 ). For those having surgery, chemotherapy, or other treatments, quitting smoking helps improve the body’s ability to heal and respond to therapy ( 1 , 3 , 27 ). It also lowers the risk of pneumonia and respiratory failure ( 1 , 3 , 28 ). In addition, quitting smoking may lower the risk that the cancer will recur, that a second cancer will develop, or that the person will die from the cancer or other causes ( 27 , 29 – 32 ).

Where can I get help to quit smoking?

NCI and other agencies and organizations can help smokers quit:

• Visit Smokefree.gov for access to free information and resources, including Create My Quit Plan , smartphone apps , and text message programs
• Call the NCI Smoking Quitline at 1–877–44U–QUIT ( 1–877–448–7848 ) for individualized counseling, printed information, and referrals to other sources.
• See the NCI fact sheet Where To Get Help When You Decide To Quit Smoking .

235 Smoking Essay Topics & Examples

Looking for smoking essay topics? Being one of the most serious psychological and social issues, smoking is definitely worth writing about.

🏆 Best Smoking Essay Examples & Topic Ideas

🥇 good titles for smoking essay, 👍 best titles for research paper about smoking, ⭐ simple & easy health essay titles, 💡 interesting topics to write about health, ❓ essay questions about smoking.

In your essay about smoking, you might want to focus on its causes and effects or discuss why smoking is a dangerous habit. Other options are to talk about smoking prevention or to concentrate on the reasons why it is so difficult to stop smoking. Here we’ve gathered a range of catchy titles for research papers about smoking together with smoking essay examples. Get inspired with us!

Smoking is a well-known source of harm yet popular regardless, and so smoking essays should cover various aspects of the topic to identify the reasons behind the trend.

You will want to discuss the causes and effects of smoking and how they contributed to the persistent refusal of large parts of the population to abandon the habit, even if they are aware of the dangers of cigarettes. You should provide examples of how one may become addicted to tobacco and give the rationales for smokers.

You should also discuss the various consequences of cigarette use, such as lung cancer, and identify their relationship with the habit. By discussing both sides of the issue, you will be able to write an excellent essay.

Reasons why one may begin smoking, are among the most prominent smoking essay topics. It is not easy to begin to enjoy the habit, as the act of smoke inhalation can be difficult to control due to a lack of experience and unfamiliarity with the concept.

As such, people have to be convinced that the habit deserves consideration by various ideas or influences. The notion that “smoking is cool” among teenagers can contribute to the adoption of the trait, as can peer pressure.

If you can find polls and statistics on the primary factors that lead people to tweet, they will be helpful to your point. Factual data will identify the importance of each cause clearly, although you should be careful about bias.

The harmful effects of tobacco have been researched considerably more, with a large body of medical studies investigating the issue available to anyone.

Lung cancer is the foremost issue in the public mind because of the general worry associated with the condition and its often incurable nature, but smoking can lead to other severe illnesses.

Heart conditions remain a prominent consideration due to their lethal effects, and strokes or asthma deserve significant consideration, as well. Overall, smoking has few to no beneficial health effects but puts the user at risk of a variety of concerns.

As such, people should eventually quit once their health declines, but their refusal to do so deserves a separate investigation and can provide many interesting smoking essay titles.

One of the most prominent reasons why a person would continue smoking despite all the evidence of its dangers and the informational campaigns carried out to inform consumers is nicotine addiction.

The substance is capable of causing dependency, a trait that has led to numerous discussions of the lawfulness of the current state of cigarettes.

It is also among the most dangerous aspects of smoking, a fact you should mention.

Lastly, you can discuss the topics of alternatives to smoking in your smoking essay bodies, such as e-cigarettes, hookahs, and vapes, all of which still contain nicotine and can, therefore, lead to considerable harm. You may also want to discuss safe cigarette avoidance options and their issues.

Here are some additional tips for your essay:

• Dependency is not the sole factor in cigarette consumption, and many make the choice that you should respect consciously.
• Cite the latest medical research titles, as some past claims have been debunked and are no longer valid.
• Mortality is not the sole indicator of the issues associated with smoking, and you should take chronic conditions into consideration.

Find smoking essay samples and other useful paper samples on IvyPanda, where we have a collection of professionally written materials!

• Conclusion of Smoking Should Be Banned on College Campuses Essay However, it is hard to impose such a ban in some colleges because of the mixed reactions that are held by different stakeholders about the issue of smoking, and the existing campus policies which give […]
• Should Smoking Be Banned in Public Places? Besides, smoking is an environmental hazard as much of the content in the cigarette contains chemicals and hydrocarbons that are considered to be dangerous to both life and environment.
• How Smoking Is Harmful to Your Health The primary purpose of the present speech is to inform the audience about the detrimental effects of smoking. The first system of the human body that suffers from cigarettes is the cardiovascular system.
• Smoking: Problems and Solutions To solve the problem, I would impose laws that restrict adults from smoking in the presence of children. In recognition of the problems that tobacco causes in the country, The Canadian government has taken steps […]
• Causes and Effects of Smoking Some people continue smoking as a result of the psychological addiction that is associated with nicotine that is present in cigarettes.
• Smoking Cigarette Should Be Banned Ban on tobacco smoking has resulted to a decline in the number of smokers as the world is sensitized on the consequences incurred on 31st May.
• On Why One Should Stop Smoking Thesis and preview: today I am privileged to have your audience and I intend to talk to you about the effects of smoking, and also I propose to give a talk on how to solve […]
• Smoking: Effects, Reasons and Solutions This presentation provides harmful health effects of smoking, reasons for smoking, and solutions to smoking. Combination therapy that engages the drug Zyban, the concurrent using of NRT and counseling of smokers under smoking cessation program […]
• Advertisements on the Effect of Smoking Do not Smoke” the campaign was meant to discourage the act of smoking among the youngsters, and to encourage them to think beyond and see the repercussions of smoking.
• Smoking and Its Negative Effects on Human Beings Therefore, people need to be made aware of dental and other health problems they are likely to experience as a result of smoking.
• Smoking Among Teenagers as Highlighted in Articles The use of tobacco through smoking is a trend among adolescents and teenagers with the number of young people who involve themselves in smoking is growing each day.
• Smoking and Youth Culture in Germany The report also assailed the Federal Government for siding the interest of the cigarette industry instead of the health of the citizens.
• Health Promotion Plan: Smokers in Mississippi The main strategies of the training session are to reduce the number of smokers in Mississippi, conduct a training program on the dangers of smoking and work with tobacco producers.
• Public Health Education: Anti-smoking Project The workshop initiative aimed to achieve the following objectives: To assess the issues related to smoking and tobacco use. To enhance the health advantages of clean air spaces.
• Smoking and Its Effects on Human Body The investigators explain the effects of smoking on the breath as follows: the rapid pulse rate of smokers decreases the stroke volume during rest since the venous return is not affected and the ventricles lose […]
• Causes and Effects of Smoking in Public The research has further indicated that the carcinogens are in higher concentrations in the second hand smoke rather than in the mainstream smoke which makes it more harmful for people to smoke publicly.
• Smoking Habit, Its Causes and Effects Smoking is one of the factors that are considered the leading causes of several health problems in the current society. Smoking is a habit that may be easy to start, but getting out of this […]
• “Thank You For Smoking” by Jason Reitman Film Analysis Despite the fact that by the end of the film the character changes his job, his nature remains the same: he believes himself to be born to talk and convince people.
• Summary of “Smokers Get a Raw Deal” by Stanley Scott Lafayette explains that people who make laws and influence other people to exercise these laws are obviously at the top of the ladder and should be able to understand the difference between the harm sugar […]
• Aspects of Anti-Smoking Advertising Thus, it is safe to say that the authors’ main and intended audience is the creators of anti-smoking public health advertisements.
• Introducing Smoking Cessation Program: 5 A’s Intervention Plan The second problem arises in an attempt to solve the issue of the lack of counseling in the unit by referring patients to the outpatient counseling center post-hospital discharge to continue the cessation program.
• Teenage Smoking and Solution to This Problem Overall, the attempts made by anti-smoking campaigners hardly yield any results, because they mostly focus on harmfulness of tobacco smoking and the publics’ awareness of the problem, itself, but they do not eradicate the underlying […]
• Smoking Qualitative Research: Critical Analysis Qualitative research allows researchers to explore a wide array of dimensions of the social world, including the texture and weave of everyday life, the understandings, experiences and imaginings of our research participants, the way that […]
• Tobacco Debates in “Thank You for Smoking” The advantage of Nick’s strategy is that it offers the consumer a role model to follow: if smoking is considered to be ‘cool’, more people, especially young ones, will try to become ‘cool’ using cigarettes.
• The Change of my Smoking Behavior With the above understanding of my social class and peer friends, I was able to create a plan to avoid them in the instances that they were smoking.
• Inequality and Discrimination: Impact on LGBTQ+ High School Students Consequently, the inequality and discrimination against LGBTQ + students in high school harm their mental, emotional, and physical health due to the high level of stress and abuse of various substances that it causes.
• Factors Affecting the Success in Quitting Smoking of Smokers in West Perth, WA Australia Causing a wide array of diseases, health smoking is the second cause of death in the world. In Australia, the problem of smoking is extremely burning due to the high rates of diseases and deaths […]
• Health Promotion for Smokers The purpose of this paper is to show the negative health complications that stem from tobacco use, more specifically coronary heart disease, and how the health belief model can help healthcare professionals emphasize the importance […]
• Gender-Based Assessment of Cigarette Smoking Harm Thus, the following hypothesis is tested: Women are more likely than men to believe that smoking is more harmful to health.
• Hazards of Smoking and Benefits of Cessation Prabhat Jha is the author of the article “The Hazards of Smoking and the Benefits of Cessation,” published in a not-for-profit scientific journal, eLife, in 2020.
• The Impact of Warning Labels on Cigarette Smoking The regulations requiring tobacco companies to include warning labels are founded on the need to reduce nicotine intake, limit cigarette dependence, and mitigate the adverse effects associated with addiction to smoking.
• Psilocybin as a Smoking Addiction Remedy Additionally, the biotech company hopes to seek approval from FDA for psilocybin-based therapy treatment as a cigarette smoking addiction long-term remedy.
• Tobacco Smoking: The Health Outcomes Tobacco smoke passing through the upper respiratory tract irritates the membrane of the nasopharynx, and other organism parts, generating copious separation of mucus and saliva.
• Investing Savings from Quitting Smoking: A Financial Analysis The progression of interest is approximately $50 per year, and if we assume n equal to 45 using the formula of the first n-terms of the arithmetic progression, then it comes out to about 105 […]
• Smoking as a Community Issue: The Influence of Smoking A review of the literature shows the use of tobacco declined between 1980 and 2012, but the number of people using tobacco in the world is increasing because of the rise in the global population.
• Smoking Public Education Campaign Assessment The major influence of the real cost campaign was to prevent the initiation of smoking among the youth and prevent the prevalence of lifelong smokers.
• Smoking Cessation Therapy: Effectiveness of Electronic Cigarettes Based on the practical experiments, the changes in the patients’ vascular health using nicotine and electronic cigarettes are improved within one-month time period. The usage only of electronic cigarettes is efficient compared to when people […]
• Quitting Smoking and Related Health Benefits The regeneration of the lungs will begin: the process will touch the cells called acini, from which the mucous membrane is built. Therefore, quitting the habit of smoking a person can radically change his life […]
• Smoking and Stress Among Veterans The topic is significant to explore because of the misconception that smoking can alleviate the emotional burden of stress and anxiety when in reality, it has an exacerbating effect on emotional stress.
• Smoking as a Predictor of Underachievement By comparing two groups smoking and non-smoking adolescents through a parametric t-test, it is possible to examine this assumption and draw conclusions based on the resulting p-value.
• Smoking and the Pandemic in West Virginia In this case, the use of the income variable is an additional facet of the hypothesis described, allowing us to evaluate whether there is any divergence in trends between the rich and the poor.
• Anti-Smoking Policy in Australia and the US The anti-smoking policy is to discourage people from smoking through various means and promotion of a healthy lifestyle, as well as to prevent the spread of the desire to smoke.
• Smoking Prevalence in Bankstown, Australia The secondary objective of the project was to gather and analyze a sufficient amount of auxiliary scholarly sources on smoking cessation initiatives and smoking prevalence in Australia.
• Drug Addiction in Teenagers: Smoking and Other Lifestyles In the first part of this assignment, the health problem of drug addiction was considered among teens and the most vulnerable group was established.
• Anti-Smoking Communication Campaign’s Analysis Defining the target audience for an anti-smoking campaign is complicated by the different layers of adherence to the issue of the general audience of young adults.
• Smoking as a Risk Factor for Lung Cancer Lung cancer is one of the most frequent types of the condition, and with the low recovery rates. If the problem is detected early and the malignant cells are contained to a small region, surgery […]
• Smoking Cessation Project Implementation In addition, the review will include the strengths and weaknesses of the evidence presented in the literature while identifying gaps and limitations.
• Smoking Cessation and Health Promotion Plan Patients addicted to tobacco are one of the major concerns of up-to-date medicine as constant nicotine intake leads to various disorders and worsens the health state and life quality of the users.
• Maternal and Infant Health: Smoking Prevention Strategies It is known that many women know the dangers of smoking when pregnant and they always try to quit smoking to protect the lives of themselves and the child.
• A Peer Intervention Program to Reduce Smoking Rates Among LGBTQ Therefore, the presumed results of the project are its introduction into the health care system, which will promote a healthy lifestyle and diminish the level of smoking among LGBTQ people in the SESLHD.
• Tackling Teenage Smoking in Community The study of the problem should be comprehensive and should not be limited by the medical aspect of the issue. The study of the psychological factor is aimed at identifying the behavioral characteristics of smoking […]
• Peer Pressure and Smoking Influence on Teenagers The study results indicate that teenagers understand the health and social implications of smoking, but peer pressure contributes to the activity’s uptake.
• Smoking Cessation Programs Through the Wheel of Community Organizing The first step of the wheel is to listen to the community’s members and trying to understand their needs. After the organizer and the person receiving treatment make the connection, they need to understand how […]
• Smoking: Benefits or Harms? Hundreds of smokers every day are looking for a way to get rid of the noose, which is a yoke around the neck, a cigarette.
• The Culture of Smoking Changed in Poland In the 1980-90s, Poland faced the challenge of being a country with the highest rates of smoking, associated lung cancer, and premature mortality in the world.
• The Stop Smoking Movement Analysis The paper discusses the ideology, objective, characteristics, context, special techniques, organization culture, target audience, media strategies, audience reaction, counter-propaganda and the effectiveness of the “Stop Smoking” Movement.”The Stop Smoking” campaign is a prevalent example of […]
• Smoking Health Problem Assessment The effects of smoking correlate starkly with the symptoms and diseases in the nursing practice, working as evidence of the smoking’s impact on human health.
• Integration of Smoking Cessation Into Daily Nursing Practice Generally, smoking cessation refers to a process structured to help a person to discontinue inhaling smoked substances. It can also be referred to as quitting smoking.
• E-Cigarettes and Smoking Cessation Many people argue that e-cigarettes do not produce secondhand smoke. They believe that the e-fluids contained in such cigarettes produce vapor and not smoke.
• Outdoor Smoking Ban in Public Areas of the Community These statistics have contributed to the widespread efforts to educate the public regarding the need to quit smoking. However, most of the chronic smokers ignore the ramifications of the habit despite the deterioration of their […]
• Nicotine Replacement Therapy for Adult Smokers With a Psychiatric Disorder The qualitative research methodology underlines the issue of the lack of relevant findings in the field of nicotine replacement therapy in people and the necessity of treatment, especially in the early stages of implementation.
• Smoking and Drinking: Age Factor in the US As smoking and drinking behavior were both strongly related to age, it could be the case that the observed relationship is due to the fact that older pupils were more likely to smoke and drink […]
• Poland’s Smoking Culture From Nursing Perspective Per Kinder, the nation’s status as one of Europe’s largest tobacco producers and the overall increase in smoking across the developing nations of Central and Eastern Europe caused its massive tobacco consumption issues.
• Smoking Cessation Clinic Analysis The main aim of this project is to establish a smoking cessation clinic that will guide smoker through the process of quitting smoking.
• Cigarette Smoking Among Teenagers in the Baltimore Community, Maryland The paper uses the Baltimore community in Maryland as the area to focus the event of creating awareness of cigarette smoking among the teens of this community.
• Advocating for Smoking Cessation: Health Professional Role Health professionals can contribute significantly to tobacco control in Australia and the health of the community by providing opportunities for smoking patients to quit smoking.
• Lifestyle Management While Quitting Smoking Realistically, not all of the set goals can be achieved; this is due to laxity in implementing them and the associated difficulty in letting go of the past lifestyle.
• Smoking in the Actuality The current use of aggressive marketing and advertising strategies has continued to support the smoking of e-cigarettes. The study has also indicated that “the use of such e-cigarettes may contribute to the normalization of smoking”.
• Analysis of the Family Smoking Prevention and Tobacco Control Act The law ensures that the FDA has the power to tackle issues of interest to the public such as the use of tobacco by minors.
• “50-Year Trends in Smoking-Related Mortality in the United States” by Thun et al. Thun is affiliated with the American Cancer Society, but his research interests cover several areas. Carter is affiliated with the American Cancer Society, Epidemiology Research Program.
• Pulmonology: Emphysema Caused by Smoking The further development of emphysema in CH can lead to such complications caused by described pathological processes as pneumothorax that is associated with the air surrounding the lungs.
• Smoking and Lung Cancer Among African Americans Primarily, the research paper provides insight on the significance of the issue to the African Americans and the community health nurses.
• Health Promotion and Smoking Cessation I will also complete a wide range of activities in an attempt to support the agency’s goals. As well, new studies will be conducted in order to support the proposed programs.
• Maternal Mental Health and Prenatal Smoking It was important to determine the variables that may lead to postpartum relapse or a relapse during the period of pregnancy. It is important to note that the findings are also consistent with the popular […]
• Nursing Interventions for Smoking Cessation For instance, the authors are able to recognize the need to classify the level of intensity in respect to the intervention that is employed by nurses towards smoking cessation.
• Smoking and Cancer in the United States In this research study, data on tobacco smoking and cancer prevalence in the United States was used to determine whether cancer in the United States is related to tobacco smoking tobacco.
• Marketing Plan: Creating a Smoking Cessation Program for Newton Healthcare Center The fourth objective is to integrate a smoking cessation program that covers the diagnosis of smoking, counseling of smokers, and patient care system to help the smokers quit their smoking habits. The comprehensive healthcare needs […]
• Smoking Among the Youth Population Between 12-25 Years I will use the theory to strengthen the group’s beliefs and ideas about smoking. I will inform the group about the relationship between smoking and human health.
• Risks of Smoking Cigarettes Among Preteens Despite the good news that the number of preteen smokers has been significantly reducing since the 1990s, there is still much to be done as the effects of smoking are increasingly building an unhealthy population […]
• Healthy People Program: Smoking Issue in Wisconsin That is why to respond to the program’s effective realization, it is important to discuss the particular features of the target population in the definite community of Wisconsin; to focus on the community-based response to […]
• Health Campaign: Smoking in the USA and How to Reduce It That is why, the government is oriented to complete such objectives associated with the tobacco use within the nation as the reduction of tobacco use by adults and adolescents, reduction of initiation of tobacco use […]
• Smoking Differentials Across Social Classes The author inferred her affirmations from the participant’s words and therefore came to the right conclusion; that low income workers had the least justification for smoking and therefore took on a passive approach to their […]
• Cigarette Smoking Side Effects Nicotine is a highly venomous and addictive substance absorbed through the mucous membrane in the mouth as well as alveoli in the lungs.
• Long-Term Effects of Smoking The difference between passive smoking and active smoking lies in the fact that, the former involves the exposure of people to environmental tobacco smoke while the latter involves people who smoke directly.
• Smoking Cessation Program Evaluation in Dubai The most important program of this campaign is the Quit and Win campaign, which is a unique idea, launched by the DHCC and is in the form of an open contest.
• Preterm Birth and Maternal Smoking in Pregnancy The major finding of the discussed research is that both preterm birth and maternal smoking during pregnancy contribute, although independently, to the aortic narrowing of adolescents.
• Enforcement of Michigan’s Non-Smoking Law This paper is aimed at identifying a plan and strategy for the enforcement of the Michigan non-smoking law that has recently been signed by the governor of this state.
• Smoking Cessation for Patients With Cardio Disorders It highlights the key role of nurses in the success of such programs and the importance of their awareness and initiative in determining prognosis.
• Legalizing Electronic Vaping as the Means of Curbing the Rates of Smoking However, due to significantly less harmful effects that vaping produces on health and physical development, I can be considered a legitimate solution to reducing the levels of smoking, which is why it needs to be […]
• Self-Efficacy and Smoking Urges in Homeless Individuals Pinsker et al.point out that the levels of self-efficacy and the severity of smoking urges change significantly during the smoking cessation treatment.
• “Cigarette Smoking: An Overview” by Ellen Bailey and Nancy Sprague The authors of the article mentioned above have presented a fair argument about the effects of cigarette smoking and debate on banning the production and use of tobacco in America.
• “The Smoking Plant” Project: Artist Statement It is the case when the art is used to pass the important message to the observer. The live cigarette may symbolize the smokers while the plant is used to denote those who do not […]
• Dangers of Smoking While Pregnant In this respect, T-test results show that mean birthweight of baby of the non-smoking mother is 3647 grams, while the birthweight of smoking mother is 3373 grams. Results show that gestation value and smoking habit […]
• The Cultural Differences of the Tobacco Smoking The Middle East culture is connected to the hookah, the Native American cultures use pipes, and the Canadian culture is linked to cigarettes.
• Ban on Smoking in Enclosed Public Places in Scotland The theory of externality explains the benefit or cost incurred by a third party who was not a party to the reasoning behind the benefit or cost. This will also lead to offer of a […]
• How Smoking Cigarettes Effects Your Health Cigarette smoking largely aggravates the condition of the heart and the lung. In addition, the presence of nicotine makes the blood to be sticky and thick leading to damage to the lining of the blood […]
• Alcohol and Smoking Abuse: Negative Physical and Mental Effects The following is a range of effects of heavy alcohol intake as shown by Lacoste, they include: Neuropsychiatric or neurological impairment, cardiovascular, disease, liver disease, and neoplasm that is malevolent.
• Smoking Prohibition: Local Issues, Personal Views This is due to the weakening of blood vessels in the penis. For example, death rate due to smoking is higher in Kentucky than in other parts of the country.
• Smoking During Pregnancy Issues Three things to be learned from the research are the impact of smoking on a woman, possible dangers and complications and the importance of smoking cessation interventions.
• The Smoking Problem: Mortality, Control, and Prevention The article presents smoking as one of the central problems for many countries throughout the world; the most shocking are the figures related to smoking rate among students. Summary: The article is dedicated to the […]
• Tobacco Smoking: Bootleggers and Baptists Legislation or Regulation The issue is based on the fact that tobacco smoking also reduces the quality of life and ruins the body in numerous ways.
• Ban Smoking in Cars Out of this need, several regulations have been put in place to ensure children’s safety in vehicles is guaranteed; thus, protection from second-hand smoke is an obvious measure that is directed towards the overall safety […]
• Smoking: Causes and Effects Considering the peculiarities of a habit and of a disease, smoking can be considered as a habit rather than a disease.
• Smoking Behavior Under Clinical Observation The physiological aspect that influences smokers and is perceived as the immediate effect of smoking can be summarized as follows: Within ten seconds of the first inhalation, nicotine, a potent alkaloid, passes into the bloodstream, […]
• Smoking and Its Effect on the Brain Since the output of the brain is behavior and thoughts, dysfunction of the brain may result in highly complex behavioral symptoms. The work of neurons is to transmit information and coordinate messengers in the brain […]
• Smoking Causes and Plausible Arguments In writing on the cause and effect of smoking we will examine the issue from the point of view of temporal precedence, covariation of the cause and effect and the explanations in regard to no […]
• Post Smoking Cessation Weight Gain The aim of this paper is to present, in brief, the correlation between smoking cessation and weigh gain from biological and psychological viewpoints.
• Marketing a Smoking Cessation Program In the case of the smoking cessation program, the target group is made up of smokers who can be further subdivided into segments such as heavy, medium, and light smokers.
• Smoking Cessation for Ages 15-30 The Encyclopedia of Surgery defines the term “Smoking Cessation” as an effort to “quit smoking” or “withdrawal from smoking”. I aim to discuss the importance of the issue by highlighting the most recent statistics as […]
• Motivational Interviewing as a Smoking Cessation Intervention for Patients With Cancer The dependent variable is the cessation of smoking in 3 months of the interventions. The study is based on the author’s belief that cessation of smoking influences cancer-treated patients by improving the efficacy of treatment.
• Media Effects on Teen Smoking But that is not how an adult human brain works, let alone the young and impressionable minds of teenagers, usually the ads targeted at the youth always play upon elements that are familiar and appealing […]
• “Passive Smoking Greater Health Hazard: Nimhans” by Stephen David The article focuses on analyzing the findings of the study and compares them to the reactions to the ban on public smoking.
• Partnership in Working About Smoking and Tobacco Use The study related to smoking and tobacco use, which is one of the problematic areas in terms of the health of the population.
• Cigar Smoking and Relation to Disease The article “Effect of cigar smoking on the risk of cardiovascular disease, chronic obstructive pulmonary disease and cancer in Men” by Iribarren et al.is a longitudinal study of cigar smokers and the impact of cigar […]
• Quitting Smoking: Motivation and Brain As these are some of the observed motivations for smoking, quitting smoking is actually very easy in the sense that you just have to set your mind on quitting smoking.
• Health Effects of Tobacco Smoking in Hispanic Men The Health Effects of Tobacco Smoking can be attributed to active tobacco smoking rather than inhalation of tobacco smoke from environment and passive smoking.
• Smoking in Adolescents: A New Threat to the Society Of the newer concerns about the risks of smoking and the increase in its prevalence, the most disturbing is the increase in the incidences of smoking among the adolescents around the world.
• The Importance of Nurses in Smoking-Cessation Programs When a patient is admitted to the hospital, the nursing staff has the best opportunity to assist them in quitting in part because of the inability to smoke in the hospital combined with the educational […]
• New Jersey Legislation on Smoking The advantages and disadvantages of the legislation were discussed in this case because of the complexity of the topic at hand as well as the potential effects of the solution on the sphere of public […]
• Environmental Health: Tabaco Smoking and an Increased Concentration of Carbon Monoxide The small size of the town, which is around 225000 people, is one of the reasons for high statistics in diseases of heart rate.
• Advanced Pharmacology: Birth Control for Smokers The rationale for IUD is the possibility to control birth without the partner’s participation and the necessity to visit a doctor just once for the device to be implanted.
• Legislation Reform of Public Smoking Therefore, the benefit of the bill is that the health hazard will be decreased using banning smoking in public parks and beaches.
• Female Smokers Study: Inferential Statistics Article The article “Differential Effects of a Body Image Exposure Session on Smoking Urge between Physically Active and Sedentary Female Smokers” deepens the behavioral mechanisms that correlate urge to smoke, body image, and physical activity among […]
• Smoking Bans: Protecting the Public and the Children of Smokers The purpose of the article is to show why smoking bans aim at protecting the public and the children of smokers.
• Clinical Effects of Cigarette Smoking Smoking is a practice that should be avoided or controlled rigorously since it is a risk factor for diseases such as cancer, affects the health outcomes of direct and passive cigarette users, children, and pregnant […]
• Public Health and Smoking Prevention Smoking among adults over 18 years old is a public health issue that requires intervention due to statistical evidence of its effects over the past decades.
• Smoking in the US: Statistics and Healthcare Costs According to the Centers for Disease Control and Prevention, tobacco smoking is the greatest preventable cause of death in the US.
• Smoking Should Be Banned Internationally The questions refer to the knowledge concerning the consequences of smoking and the opinions on smoking bans. 80 % of respondents agree that smoking is among the leading causes of death and 63, 3 % […]
• Microeconomics: Cigarette Taxes and Public Smoking Ban The problem of passive smoking will be minimized when the number of smokers decreases. It is agreeable that the meager incomes of such families will be used to purchase cigarettes.
• Alcohol and Smoking Impact on Cancer Risk The research question is to determine the quantity of the impact that different levels of alcohol ingestion combined with smoking behavioral patterns make on men and women in terms of the risks of cancer.
• Teenagers Motivated to Smoking While the rest of the factors also matter much in the process of shaping the habit of smoking, it is the necessity to mimic the company members, the leader, or any other authority that defines […]
• Indoor Smoking Restriction Effects at the Workplace Regrettably, they have neglected research on the effect of the legislation on the employees and employers. In this research, the target population will be the employees and employers of various companies.
• Hypnotherapy Session for Smoking Cessation When I reached the age of sixty, I realized that I no longer wanted to be a smoker who was unable to take control of one’s lifestyle.
• Stopping Tobacco Smoking: Lifestyle Management Plan In addition, to set objective goals, I have learned that undertaking my plan with reference to the modifying behaviour is essential for the achievement of the intended goals. The main intention of the plan is […]
• Smoking Epidemiology Among High School Students In this way, with the help of a cross-sectional study, professionals can minimalize the risk of students being afraid to reveal the fact that they smoke. In this way, the number of students who smoke […]
• Social Marketing: The Truth Anti-Smoking Campaign The agreement of November 1998 between 46 states, five territories of the United States, the District of Columbia, and representatives of the tobacco industry gave start to the introduction of the Truth campaign.
• Vancouver Coastal Health Smoking Cessation Program The present paper provides an evaluation of the Vancouver Coastal Health smoking cessation program from the viewpoint of the social cognitive theory and the theory of planned behavior.
• Smoking Experience and Hidden Dangers When my best college friend Jane started smoking, my eyes opened on the complex nature of the problem and on the multiple negative effects of smoking both on the smoker and on the surrounding society.
• South Illinois University’s Smoking Ban Benefits The purpose of this letter is to assess the possible benefits of the plan and provide an analysis of the costs and consequences of the smoking ban introduction.
• Smoking Cessation in Patients With COPD The strategy of assessing these papers to determine their usefulness in EBP should include these characteristics, the overall quality of the findings, and their applicability in a particular situation. The following article is a study […]
• Smoking Bans: Preventive Measures There have been several public smoking bans that have proved to be promising since the issue of smoking prohibits smoking in all public places. This means it is a way of reducing the exposure to […]
• Ban Smoking Near the Child: Issues of Morality The decision to ban smoking near the child on father’s request is one of the demonstrative examples. The father’s appeal to the Supreme Court of California with the requirement to prohibit his ex-wife from smoking […]
• The Smoking Ban: Arguments Comparison The first argument against banning smoking employs the idea that smoking in specially designated areas cannot do harm to the health of non-smokers as the latter are supposed to avoid these areas.
• Smoking Cessation and Patient Education in Nursing Pack-years are the concept that is used to determine the health risks of a smoking patient. The most important step in the management plan is to determine a date when the man should quit smoking.
• Philip Morris Company’s Smoking Prevention Activity Philip Morris admits the existence of scientific proof that smoking leads to lung cancer in addition to other severe illnesses even after years of disputing such findings from health professionals.
• Tobacco Smoking and Its Dangers Sufficient evidence also indicates that smoking is correlated with alcohol use and that it is capable of affecting one’s mental state to the point of heightening the risks of development of disorders.
• Virginia Slims’ Impact on Female Smokers’ Number Considering this, through the investigation of Philip Morris’ mission which it pursued during the launch of the Virginia Slims campaign in 1968-1970 and the main regulatory actions undertaken by the Congress during this period, the […]
• Cigarette Smoking and Parkinson’s Disease Risk Therefore, given the knowledge that cigarette smoking protects against the disease, it is necessary to determine the validity of these observations by finding the precise relationship between nicotine and PD.
• Tuberculosis Statistics Among Cigarette Smokers The proposal outlines the statistical applications of one-way ANOVA, the study participants, the variables, study methods, expected results and biases, and the practical significance of the expected results.
• Smoking Ban and UK’s Beer Industry However, there is an intricate type of relationship between the UK beer sector, the smoking ban, and the authorities that one can only understand by going through the study in detail The history of smoking […]
• Status of Smoking around the World Economic factors and level of education have contributed a lot to the shift of balance in the status of smoking in the world.
• Redwood Associates Company’s Smoking Ethical Issues Although employees are expected to know what morally they are supposed to undertake at their work place, it is the responsibility of the management and generally the Redwood’s hiring authority to give direction to its […]
• Smokers’ Campaign: Finding a Home for Ciggy Butts When carrying out the campaign, it is important to know what the situation on the ground is to be able to address the root cause of the problem facing the population.
• Mobile Applications to Quit Smoking A critical insight that can be gleaned from the said report is that one of the major factors linked to failure is the fact that smokers were unable to quit the habit on their own […]
• Behavior Modification Technique: Smoking Cessation Some of its advantages include: its mode of application is in a way similar to the act of smoking and it has very few side effects.
• Quitting Smoking: Strategies and Consequences Thus, for the world to realize a common positive improvement in population health, people must know the consequences of smoking not only for the smoker but also the society. The first step towards quitting smoking […]
• Effects of Thought Suppression on Smoking Behavior In the article under analysis called I suppress, Therefore I smoke: Effects of Thought Suppression on Smoking Behavior, the authors dedicate their study to the evaluation of human behavior as well as the influence of […]
• Suppressing Smoking Behavior and Its Effects The researchers observed that during the first and the second weeks of the suppressed behavior, the participants successfully managed to reduce their intake of cigarettes.
• Smoking Cessation Methods These methods are a part of NRT or nicotine replacement therapy, they work according to the principle of providing the smoker with small portions of nicotine to minimize the addiction gradually and at the same […]
• Understanding Advertising: Second-Hand Smoking The image of the boy caught by the smoke is in the center of the picture, and it is in contrast with the deep black background.
• People Should Quit Smoking
• Importance of Quitting Smoking
• Cigarette Smoking in Public Places
• Ban of Tobacco Smoking in Jamaica
• Anti-Smoking Campaign in Canada
• Electronic Cigarettes: Could They Help University Students Give Smoking Up?
• Psychosocial Smoking Rehabilitation
• The Program on Smoking Cessation for Employees
• Tips From Former Smokers (Campaign)
• Combating Smoking: Taxation Policies vs. Education Policies
• The Program to Quit Smoking
• Smoking Culture in Society
• Possible Smoking Policies in Florida
• Smoking Ban in the State of Florida
• Core Functions of Public Health in the Context of Smoking and Heart Disease
• Smoking: Pathophysiological Effects
• Putting Out the Fires: Will Higher Taxes Reduce the Onset of Youth Smoking?
• Hookah Smoking and Its Risks
• Smoking Bans in US
• Smoking as Activity Enhancer: Schizophrenia and Gender
• Health Care Costs for Smokers
• Medical Coverage for Smoking Related Diseases
• Exposure to mass media proliferate smoking
• The Realm of reality: Smoking
• Ethical Problem of Smoking
• The Rate of Smoking Among HIV Positive Cases.
• Studying the Government’s Anti-Smoking Measures
• Smoking Should Be Banned In the United States
• Effectiveness of Cognitive Behavioral Theory on Smoking Cessation
• Effectiveness of the Cognitive Behavioral Therapy for Smoking Cessation
• Wayco Company’s Non-smoking Policy
• Adverse Aspects of Smoking
• Negative Impacts of Smoking on Individuals and Society
• Dealing With the Increase in the Number of Smokers Between Ages 17 and 45
• Cannabis Smoking in Canada
• Smoking Ban in the United States of America
• Dangers of Smoking Campaign
• Should Cigarettes Be Banned? Essay
• Smoking Ban in New York
• Smoking and Adolescents
• Trends in Smoking Prevalence by Race/Ethnicity
• Business Ethics: Smoking Issue
• Should Smoking Tobacco Be Classified As an Illegal Drug?
• Where Does the Path to Smoking Addiction Start?
• Public Health Communication: Quit Smoking
• Are Estimated Peer Effects on Smoking Robust?
• Are There Safe Smoking and Tobacco Options?
• What Are the Health Risks of Smoking?
• Does Cigarette Smoking Affect Body Weight?
• Does Cigarette Smuggling Prop Up Smoking Rates?
• What Foods Help You Quit Smoking?
• How Can People Relax Without Smoking?
• Does Education Affect Smoking Behaviors?
• Is Vaping Worse Than Smoking?
• Do Movies Affect Teen Smoking?
• What Is Worse: Drinking or Smoking?
• Does Smoking Affect Breathing Capacity?
• Does Smoking Cause Lung Cancer?
• Does Having More Children Increase the Likelihood of Parental Smoking?
• Does Smoking Cigarettes Relieve Stress?
• Does Time Preference Affect Smoking Behavior?
• How Does Smoking Affect Cardiovascular Endurance?
• How Hypnosis Can Help You Quit Smoking?
• How Does Smoking Affect Brain?
• How Nicotine Affects Your Quit Smoking Victory?
• How Does Secondhand Smoking Affect Us?
• Why Is Smoking Addictive?
• How Smoking Bans Are Bad for Business?
• Why Smoking Should Not Be Permitted in Restaurants?
• Why Public Smoking Should Be Banned?
• Why Has Cigarette Smoking Become So Prominent Within the American Culture?
• What Makes Smoking and Computers Similar?
• Does Smoking Affect Schooling?
• What Effects Can Cigarette Smoking Have on the Respiratory System?
• What Are the Most Prevalent Dangers of Smoking and Drinking?
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IvyPanda . "235 Smoking Essay Topics & Examples." February 29, 2024. https://ivypanda.com/essays/topic/smoking-essay-examples/.

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Smoking and cancer: What percentage of smokers get lung cancer?

H ave you wondered what percentage of smokers get lung cancer, and how smoking affects all the body parts because of the harmful carcinogens from the fumes that come out from a cigarette or a vape?

Other than lung cancer, smoking causes several other types of cancers and complications, so smoking is not encouraged, therefore, if are are a user, you should consider quitting immediately.

Any amount of smoking for any time period can cause cardiovascular diseases and even lead to cancer, so the longer you smoke, the more your cancer-prone you become.

Let's now delve deep into how much harm can smoking cause, and what percentage of smokers get lung cancer.

What percentage of smokers get lung cancer?

What percentage of smokers get lung cancer:According to the Centers for Disease Control and Prevention, lung cancer caused by smoking is seen in 10-20% of smokers.

Nine of ten people who smoke have the risk of getting this disease, and it depends on how much you smoke and for how long you have been smoking. The ones who are affected by lung cancer die very young if they do not get proper treatment.

Nicotine is what makes cigarettes addictive, and once you are used to it, it's very difficult to leave it completely. But every time you smoke , you are exposed to toxic fumes that not only damage your lungs and decrease lung capacity but also affect other organs.

Why do most smokers do not get lung cancer?

According to a study by scientists at Albert Einstein College of Medicine published in natural genetics, smokers develop robust mechanisms that protect them from lung cancer by limiting mutations.

A co-senior author of the same study named Professor Simon Spivack said:

"This may prove to be an important step toward the prevention and early detection of lung cancer risk and away from current Herculean efforts needed to battle late-stage disease, where the majority of health expenditures and misery occur."

What are the other cancers caused by smoking?

• Cervical cancer
• Liver cancer
• Mouth cancer
• Throat cancer
• Bladder cancer and the list goes on.

Smoking can also cause high blood pressure , blood clots, damage to arteries, type 2 diabetes, poor vision, erectile dysfunction in men and fertility issues in females.

Lung cancer treatment

If you're a chain smoker, you must do an annual lung cancer screening to check your lung health and capacity first.

If you're diagnosed with lung cancer, you will have to discuss with your doctor about the treatment. It will depend on a lot of factors, including your age, stage of cancer and more.

If you opt for surgery, the surgeon might remove a small or a large portion of your lung, which is affected. Sometimes an entire lobe is removed too, and chemotherapy could be used along with radiation therapy or a lung surgery to stop a relapse.

Immunotherapy can also be used to treat lung cancer for cases that are in the last stages, have spread to other organs and need immediate attention.

What are your chances of recovering?

It depends on a lot of factors. According to CANCER RESEARCH UK, people who are in stage one of this cancer type - 65% of them live for five years or more after they are found to have the disease.

With the second stage, the chances of survival come down to 40%, while with the third stage, it's 15%. In the fourth and final stage, the chances of survival become as low as 5%.

Every time you buy a pack of cigarettes or a vape, think about the consequences by just looking at the warning on the label. Do not let smoking take your life.

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Let’s start with some facts. Antiperspirants, cell phones, root canals or wired bras do not cause cancer. Sugar or dairy products do not “feed” the disease. You cannot cure cancer with an alkaline diet, crystals, juices, shark cartilage, apricot pits, magnets, mistletoe, soursop, chlorella, black walnuts, coconut oil, cesium chloride, reiki, psychic surgery, baking soda, antineoplastons, bioresonance machines, orgone accumulators, Rife frequency generators or coffee enemas.

All of this comes to mind now because I was forwarded a link to a document entitled “Everyday Products Linked to Cancer” which also offers solutions to the problem. So, I clicked. I quickly learned that the discoverer of “the missing link” to “conquering cancer” is identified as a “natural health researcher and certified holistic cancer coach.” That immediately set my alarm bells ringing. This is not terminology that would ever be used to describe a legitimate scientist. And those bells really started to clamor when I encountered phrases like “groundbreaking,” “unveil cancer care known only to a few,” “challenge the one-sided, conventional understanding and offer more effective ways to conquer cancer,” “discover the proven protocols that have helped hundreds of thousands of people prevent and conquer cancer,” and “discover why many cancer treatments and prevention protocols fail.”

It seems Nathan Crane, also described as a “plant-based athlete,” has found the secret that has eluded thousands and thousands of researchers around the globe and is now equipped to “pave the way for future generations to live cancer free.” A search for this sage’s educational background reveals only that he went to Belgrade High School in Montana.

What is the key to living cancer-free? Staying away from “toxic household and personal care products” and “turning to nature” for replacements. Of course, we also need to fortify our body against toxins. How? By making use of “the power of nature’s detoxifiers.” Let me point out that the term “detoxify” is generally indicative of pseudoscience since the toxins being removed are never identified nor is the mechanism by which they are eliminated elucidated.

There is nothing novel in this “Conquering Cancer” manuscript. The Internet and bookstores brim with articles and books about purported carcinogens in everyday products and secret cures hidden by “Big Pharma” for fear of losing profits from the sale of ineffective, toxic chemotherapeutic agents. The idea of secret cures is nonsense, but when it comes to chemicals found in consumer products, there are some legitimate issues. However, fear-mongering documents, such as this one, generally smack of an ignorance of dose-response relationships and claim to have greater knowledge of the impact of these chemicals on health than what actually exists. Suppositions are presented as facts.

Some personal care products and cleaning agents contain chemicals that can be classified as endocrine disruptors or carcinogens. Furthermore, some of these can be detected in our bloodstream and urine. But it is critical to understand that the presence of a chemical cannot be equated to the presence of risk. Labeling a substance as an endocrine disruptor or carcinogen is in general based on cell culture or animal studies that use amounts far greater than what humans can possibly encounter. This does not mean that concerns about the likes of phthalates, bisphenol A, dioxane and nonylphenol ethoxylates should be swept under the carpet, but proclamations that “we’re poisoning ourselves” by using products that contain traces of these substances magnify whatever risk they may pose in an unrealistic fashion.

While reducing our use of products that contain chemicals that have the shadow of carcinogen or endocrine disruptor hanging over them has merit, the claim that turmeric, ginger, cayenne pepper, cinnamon, frankincense, Camu Camu or blueberries are “nature’s detoxifiers” and protect us from cancer is not evidence-based.

However, my biggest problem with this publication is the simplistic view it presents about preventing cancer. This is a very complex disease in which genetics, diet, infections, overweight, smoking, alcohol consumption, certain chemicals, exposure to ionizing radiation, changes in hormone levels, physical activity and age can all play roles. Suggestions that cancer risk can be significantly reduced by adding turmeric to the diet or replacing a commercial cleaning agent with vinegar, or switching from store-bought shampoo to a homemade concoction of aloe vera gel, coconut milk and castile soap, are naïve.

Something else is bothersome about this publication. The talk about “dangerous” everyday products and the use of herbs to “bolster our natural defenses” seems to be just bait to hook people to click on a link to a docuseries about “Conquering Cancer.” We are asked if we are “ready to explore the hidden cause of cancer that has eluded experts for years” and told that we will discover “how to starve your cancer cells without chemo, radiation or surgery.” The latter is a hallmark of quackery.

I did not take the bait because I follow cancer research closely and know that there are no hidden causes or magical cures. Certainly not any that have been discovered by a “certified holistic cancer coach.” I also suspect that if I were to click on the link for a “free ticket” to the series that promises to reveal “how natural, proven methods have helped over 591,753 people prevent and treat this life-threatening disease,” I might at some point be prompted to dig out my credit card for some over-hyped dietary supplement or a book with an assortment of twisted facts. But that’s just a guess.

@JoeSchwarcz

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Tobacco smoking: Health impact, prevalence, correlates and interventions

Robert west.

a Department of Behavioural Science and Health , University College London , London, UK

Background and objectives : Despite reductions in prevalence in recent years, tobacco smoking remains one of the main preventable causes of ill-health and premature death worldwide. This paper reviews the extent and nature of harms caused by smoking, the benefits of stopping, patterns of smoking, psychological, pharmacological and social factors that contribute to uptake and maintenance of smoking, the effectiveness of population and individual level interventions aimed at combatting tobacco smoking, and the effectiveness of methods used to reduce the harm caused by continued use of tobacco or nicotine in some form.

Results and conclusions : Smoking behaviour is maintained primarily by the positive and negative reinforcing properties of nicotine delivered rapidly in a way that is affordable and palatable, with the negative health consequences mostly being sufficiently uncertain and distant in time not to create sufficient immediate concern to deter the behaviour. Raising immediate concerns about smoking by tax increases, social marketing and brief advice from health professionals can increase the rate at which smokers try to stop. Providing behavioural and pharmacological support can improve the rate at which those quit attempts succeed. Implementing national programmes containing these components are effective in reducing tobacco smoking prevalence and reducing smoking-related death and disease.

Introduction

The continued popularity of tobacco smoking appears to defy rational explanation. Smokers mostly acknowledge the harm they are doing to themselves and many report that they do not enjoy it – yet they continue to smoke (Fidler & West, 2011 ; Ussher, Brown, Rajamanoharan, & West, 2014 ). The reason is that nicotine from cigarettes generates strong urges to smoke that undermine and overwhelm concerns about the negative consequences of smoking, and the resolve not to smoke in those trying to stop (West & Shiffman, 2016 ). Progress is being made in many countries in reducing smoking prevalence but it remains one of the main causes of ill health and premature death worldwide (Gowing et al., 2015 ).

This paper provides a broad overview of smoking in terms of: the health effects, benefits of stopping, prevalence and patterns of use, psychological, pharmacological and social factors leading to uptake and maintenance of the behaviour, effectiveness of population level and individual level interventions to combat it, and methods used to reduce the harm despite continued use of tobacco or nicotine.

Definitions of smoking and smoking cessation

Tobacco smoking consists of drawing into the mouth, and usually the lungs, smoke from burning tobacco (West & Shiffman, 2016 ). The type of product smoked is most commonly cigarettes, but can also include cigarillos, cigars, pipes or water pipes. ‘Smokeless’ tobacco is also popular in some parts of the world. This typically involves using tobacco preparations for chewing, sniffing into the nose or placing as a wad in the mouth between the cheeks and gums (Critchley & Unal, 2003 ). Smokeless tobacco use has features that are similar to smoking and can carry significant health risks (Critchley & Unal, 2003 ); however, this article focuses on smoked tobacco only as this has been the subject of by far the largest volume of research and is the most harmful form of tobacco use.

Stopping smoking usually involves an intention not to smoke any more cigarettes from a given point in time (a ‘quit attempt’), followed by self-conscious resistance of urges to smoke resulting in a period of abstinence. If someone making a quit attempt smokes one or more cigarettes on an occasion but then resumes abstinence, this is usually termed a ‘lapse’. If this person resumes smoking on a regular basis s/he is said to have ‘relapsed’. ‘Short-term abstinence’ is commonly defined in terms of achieving up to 4 weeks of abstinence. ‘Long-term abstinence’ often refers to abstinence for at least 6 months but more typically involves abstinence for at least 12 months. There is no agreed criterion for deciding when someone has ‘stopped smoking’ so it is essential when using the term to be clear about how long the abstinence period has been.

Health impact of smoking and the benefits of stopping

Tobacco smoking increases the risk of contracting a wide range of diseases, many of which are fatal. Stopping smoking at any age is beneficial compared with continuing to smoke. For some diseases, the risk can be reversed while for others the risk is approximately frozen at the point when smoking stopped.

Health impact of smoking

Table ​ Table1 1 lists the main causes of death from smoking. Tobacco smoking is estimated to lead to the premature death of approximately 6 million people worldwide and 96,000 in the UK each year (Action on Smoking and Health, 2016b ; World Health Organization, 2013 ). A ‘premature death from smoking’ is defined as a death from a smoking-related disease in an individual who would otherwise have died later from another cause. On average, these premature deaths involve 10 years of life years lost (US Department of Health and Human Services, 2004 ). Many of these deaths occur in people who have stopped smoking but whose health has already been harmed by smoking. It also happens to be the case that smokers who do not stop smoking lose an average of 10 years of life expectancy compared with never-smokers and they start to suffer diseases of old age around 10 years earlier than non-smokers (Jha & Peto, 2014 ).

Most smoking-related deaths arise from cancers (mainly lung cancer), respiratory disease (mainly chronic obstructive pulmonary disease – COPD), and cardiovascular disease (mainly coronary heart disease) (Action on Smoking and Health, 2016b ). Smoking is an important risk factor for stroke, blindness, deafness, back pain, osteoporosis, and peripheral vascular disease (leading to amputation) (US Department of Health and Human Services, 2004 ). After the age of 40, smokers on average have higher levels of pain and disability than non-smokers (US Department of Health and Human Services, 2004 ).

Smoking in both women and men reduces fertility (Action on Smoking and Health, 2013 ). Smoking in pregnancy causes underdevelopment of the foetus and increases the risk of miscarriage, neonatal death, respiratory disease in the offspring, and is probably a cause of mental health problems in the offspring (Action on Smoking and Health, 2013 ).

People used to think that smoking was protective against Alzheimer’s disease but we now know that the opposite is the case: it is a major risk factor for both Alzheimer’s and vascular dementia (Ferri et al., 2011 ; US Department of Health and Human Services, 2004 ).

There is a positive association between average daily cigarette consumption and risk of smoking-related disease, but in the case of cardiovascular disease the association is non-linear, so that low levels of cigarette consumption carry a higher risk than would be expected from a simple linear relationship (US Department of Health and Human Services, 2004 ).

Tobacco smoke contains biologically significant concentrations of known carcinogens as well as many other toxic chemicals. Some of these, including a number of tobacco-specific nitrosamines (particularly NNK and NNN) are constituents of tobacco, largely as a result of the way it is processed, while others such as benzopyrine result from combustion of tobacco (Action on Smoking and Health, 2014b ). These chemicals form part of the particulate matter in smoke. Tobacco smoke also contains the gas, carbon monoxide (CO). CO is a potent toxin, displacing oxygen from haemoglobin molecules. However, acutely the amount of CO in tobacco smoke is too small to lead to hypoxia and the body produces increased numbers of red blood cells to compensate.

The nicotine in tobacco smoke may cause a small part of the increase in cardiovascular disease but none or almost none of the increase in risk of respiratory disease or cancer (Benowitz, 1997 , 1998 ). It is the other components of cigarette smoke that do almost all the damage. It has been proposed on the basis of studies with other species that nicotine damages the adolescent brain but there is no evidence for clinically significant deficits in cognition or emotion in adults who smoked during adolescence and then stopped (US Department of Health and Human Services, 2004 ).

Exposure to second-hand smoke carries a significant risk for both children and adults. Thus, non-smokers who are exposed to a smoky environment have an increased risk of cancer, heart disease and respiratory disease (Action on Smoking and Health, 2014a ).

Benefits of stopping smoking

Table ​ Table1 1 lists the main benefits of stopping smoking. Smokers who stop before their mid-30s have approximately the same life expectancy as never smokers (Doll, Peto, Boreham, & Sutherland, 2004 ; Pirie, Peto, Reeves, Green, & Beral, 2013 ). After the age of 35 years or so, stopping smoking recovers 2–3 months of healthy life expectancy for every year of smoking avoided, or 4–6 h for every day (Jha & Peto, 2014 ).

Stopping smoking has different effects on different smoking-related diseases. Excess risk of heart attack caused by smoking reduces by 50% within 12 months of stopping smoking. Stopping smoking returns the rate of decline in lung function to the normal age-related decline, but does not reverse this; it reduces the frequency of ‘exacerbations’ (acute attacks of breathing difficulty resulting in death or hospitalisation) in COPD patients (US Surgeon General, 1990 ). Stopping smoking ‘freezes’ the risk of smoking-related cancers at the level experienced when stopping occurs but does not decrease it in absolute terms (US Surgeon General, 1990 ).

Smokers who stop show reduced levels of stress and mood disorder than those who continue (Royal College of Physicians and Royal College of Psychiatrists, 2013 ). They also report higher levels of happiness and life satisfaction than those who continue (Shahab & West, 2009 , 2012 ). This suggests that smoking may harm mental health, though other explanations cannot be ruled out on the current evidence.

Prevalence and patterns of smoking

Smoking prevalence.

There are estimated to be approximately 1 billion tobacco smokers worldwide (Eriksen, Mackay, & Ross, 2013 ), amounting to approximately 30% of men and 7% of women (Gowing et al., 2015 ).

Cigarette smoking prevalence in Great Britain was estimated to be 16.9% in 2015, the most recent year for which figures are available at the time of writing: slightly lower in women than men (Office of National Satistics, 2016 ). Smoking in Great Britain has declined by 0.7 percentage points per year since 2001 (from 26.9% of adults in 2001). In Australia, daily cigarette smoking has declined by 0.6 percentage points per year over a similar time period (from 22.4% of adults aged 18 + years in 2001 to 14.5% in 2015) (Australian Bureau of Statistics, 2015 ). However, international comparisons are confused by different countries using a different definition of what counts as being a smoker, and different methods for assessing prevalence. Australia only counts daily smokers in their headline figures. The situation in the US is even more misleading. The headline prevalence figure for the US is below 16%, but this does not include occasional smokers and people who smoke cigarillos which are essentially cigarettes in all but name and which have become increasingly popular in recent years. So the figure for prevalence that is most comparable to the figure for Great Britain is 20% (Jamal, 2016 ).

With the above caveats in mind, the figures in Table ​ Table2 2 for smoking prevalence in world regions in men and women provide very broad estimates (Gowing et al., 2015 ). Most noteworthy is that smoking prevalence in men is more than four times that in women globally but that the difference is much less in most parts of Europe, and that Eastern Europe as a whole has the highest smoking prevalence of any region in the world.

Note: Current smoking of any tobacco product, adults aged 15 years and older, age-standardised rate, by gender. ‘Tobacco smoking’ includes cigarettes, cigars, pipes or any other smoked tobacco products. ‘Current smoking’ includes both daily and non-daily or occasional smoking. From Gowing et al. ( 2015 ).

Smoking patterns

The most common age of first trying a cigarette in countries that have been studied is 10–15 years (Action on Smoking and Health, 2015b ; Talip, Murang, Kifli, & Naing, 2016 ); take up of regular smoking usually continues up to early 20s (Dierker et al., 2008 ).

Average daily cigarette consumption among smokers in the US and UK has declined steadily since the 1970s. In the UK, it is currently 11 cigarettes per day, and non-daily smoking is very rare (Action on Smoking and Health, 2016c ; Jarvis, Giovino, O’Connor, Kozlowski, & Bernert, 2014 ). Smokers take in an average of 1–1.5 mg of nicotine per cigarette (US Department of Health Human Services, 2014 ). The US figures on patterns of smoking are distorted by not counting ‘cigarillos’ and other smoked tobacco products which are used very much like cigarettes, whose prevalence has increased in recent years (Jamal et al., 2015 ). The reduction in daily cigarette consumption has not been accompanied by a reduction in daily nicotine intake (Jarvis et al., 2014 ). This could be due to the use of other smoked tobacco products (in the case of the US) or smokers smoking their cigarettes more intensively (taking more, deeper or longer puffs).

Smokers in England spend an average of £23 per week on cigarettes and this figure is slowly rising (West & Brown, 2015 ). In the UK, hand-rolled cigarettes have become increasingly popular with 34% of smokers currently reporting use of these products (Action on Smoking and Health, 2016c ). Men and people in more deprived socio-economic groups are more likely to smoke hand-rolled cigarettes (Action on Smoking and Health, 2016c ).

In most countries, there are strong negative associations between smoking prevalence and educational level, affluence and mental health; and positive associations with alcohol use disorder and substance use disorder (Action on Smoking and Health, 2016a , 2016c ; Royal College of Physicians and Royal College of Psychiatrists, 2013 ; Talati, Keyes, & Hasin, 2016 ). In the UK, average daily cigarette consumption is higher for men than women, and higher in smokers in more deprived socio-economic groups and those with mental health problems (Action on Smoking and Health, 2016c ).

Psychological, pharmacological and social factors involved in smoking and smoking cessation

The natural history of smoking can be modelled as states and factors that influence the transition between these. Figure ​ Figure1 1 shows transitions that have been researched – the variables identified in the diagram are listed descriptively without attempting to explain how they may be connected.

Factors associated with transitions in the natural history of smoking (parentheses indicate negative associations).

Smoking initiation

Important factors predicting initiation in western societies are: having friends who smoke, having parents who smoke, low social grade, tendency to mental health problems and impulsivity (Action on Smoking and Health, 2015b ). Transition to daily smoking follows a highly variable pattern sometimes being very rapid and sometimes taking several years (Schepis & Rao, 2005 ). Important factors predicting transition to regular smoking are: having friends who smoke, weak academic orientation, low parental support, pro-smoking attitudes, drinking alcohol and low socio-economic status (Action on Smoking and Health, 2015b ).

Smoking initiation has a ‘heritability’ (the proportion of variance in a characteristic that is attributable to genetic rather than environmental variance) of approximately 30–50% in western societies (Vink, Willemsen, & Boomsma, 2005 ). This means that differences in genetic make-up account for almost half of the difference in likelihood of starting smoking between individuals. This does not mean that environmental factors do not also play a crucial role as is evident from the very large decline in smoking initiation since the 1970s in many western countries.

The heritability of cigarette addiction (as distinct from smoking) is approximately 70–80% in western societies (Vink et al., 2005 ). Cigarette addiction here refers to the extent to which someone experiences a strong need to smoke. It is usually indexed by a combination of number of cigarettes per day and time from waking to smoking the first cigarette of the day (Kozlowski, Porter, Orleans, Pope, & Heatherton, 1994 ). It can also be indexed by the self-reported strength of urges to smoke (Fidler, Shahab, & West, 2011 ). Heritability of cigarette addiction, as indexed by failure of attempts to stop, is higher than the heritability for smoking and for initiation of smoking. This suggests that differences in genetic inheritance play a larger role in being able to stop smoking than in starting to smoke.

Cigarette addiction

Cigarette addiction stems from the fact that smoking provides highly controllable doses of the drug, nicotine, rapidly to the brain in a form that is accessible, affordable and palatable (West, 2009 ; West & Shiffman, 2016 ). Nicotine provided more slowly, for example by the nicotine transdermal patch, is much less addictive. It is possible that one or more mono-amine oxidase inhibitors in cigarette smoke add to, or synergise, the addictive properties of nicotine (Hogg, 2016 ).

The psychopharmacology of cigarette addiction is complex and far from fully understood. The following paragraphs summarise the current narrative.

Nicotine resembles the naturally occurring neurotransmitter, acetylcholine, sufficiently to attach itself to a subset of neuronal receptors for this neurotransmitter in the brain. These are called ‘nicotinic acetylcholine receptors’. When it does this with receptors in the ventral tegmental area in the midbrain, it causes an increased rate of firing of the nerves projecting forward from that area to another part of the brain called the nucleus accumbens. This causes release of another neurotransmitter called dopamine in the nucleus accumbens.

Dopamine release and uptake by neurones in the nucleus accumbens is believed to be central to all addictive behaviours. It acts as a neural ‘teaching signal’ which causes the brain to form an association between the current situation as perceived and the impulse to engage in whatever action immediately preceded this release. In the case of smoking, this creates an urge to smoke in situations in which smoking frequently occurs. These are often referred to as ‘cue-driven smoking urges’ or ‘situational cravings’ (West, 2009 ; West & Shiffman, 2016 ). This explains why even non-daily smokers often find it difficult to stop smoking altogether.

Repeated ingestion of nicotine from cigarettes causes changes to the functioning of the ventral tegmental area and nucleus accumbens such that when brain concentrations of nicotine are lower than usual, there is an abnormally low level of neural activity in these regions. This leads to feelings of need for behaviours that have in the past restored normal functioning, typically smoking. This feeling of need can be thought of as a kind of ‘nicotine hunger’, also called ‘background craving’ (West, 2009 ; West & Shiffman, 2016 ). This is probably why time between waking and first cigarette of the day is a useful predictor of difficulty stopping smoking (Vangeli, Stapleton, Smit, Borland, & West, 2011 ). So ‘cue-driven smoking urges’ and ‘nicotine hunger’ are important factors contributing to smoking behaviour and thought to be the primary mechanisms underpinning cigarette addiction (West, 2009 ; West & Shiffman, 2016 ).

When smokers abstain from cigarettes, within a few hours many of them start to experience nicotine withdrawal symptoms. Withdrawal symptoms from a drug are temporary symptoms that arise when the drug dose is reduced or use is terminated. They arise from neural adaptation to the presence of the drug in the central nervous system. For smoking, the most common early onset symptoms are: irritability, restlessness and difficult concentrating. Depression and anxiety have also been observed in some smokers. These symptoms typically last 1 to 4 weeks (West, 2009 ; West & Shiffman, 2016 ).

After a day or two of stopping smoking, many smokers experience other symptoms: increased appetite, constipation, mouth ulcers, cough, and weight gain. Increased appetite tends to last for at least 3 months; weight gain (averaging around 6 kg) tends to be permanent; other symptoms tend to last a few weeks. The increased appetite, weight gain and constipation arise from termination of nicotine intake but the others are probably related to other effects of stopping smoking (West, 2009 ; West & Shiffman, 2016 ).

Any of the above effects of abstinence may in individual cases promote resumption of smoking following a quit attempt but statistically the association is inconsistent and weak; the main factors driving relapse appear to be cue-driven smoking urges and nicotine hunger (Fidler & West, 2011 ; West, 2009 ; West & Shiffman, 2016 ).

Many smokers report that smoking helps them cope with stress and increases their ability to concentrate. However, this appears to be because when they go for a period without smoking they experience nicotine withdrawal symptoms that are relieved by smoking. Long-term smokers who stop report lower levels of stress than when they were smoking and no reduction in ability to concentrate (West, 2009 ; West & Shiffman, 2016 ).

It is commonly thought that smokers with mental health problems are using cigarettes to ‘self-medicate’ or treat their psychological symptoms. However, the evidence indicates that neither nicotine nor smoking improves psychological symptoms, and people with serious mental health disorders who stop smoking do not experience a worsening of mental health. In fact some studies have found an improvement (Royal College of Physicians and Royal College of Psychiatrists, 2013 ).

Smoking cessation

For most smokers, cessation requires a determined attempt to stop and then sufficient resolve in the following weeks and months to overcome what are often powerful urges to smoke. Factors that predict quit attempts differ from those that predict the success of those attempts (Vangeli et al., 2011 ). Approximately 5% of unaided quit attempts succeed for at least 6 months (Hughes, Keely, & Naud, 2004 ). Relapse after this point is estimated to be around 50% over subsequent years (Stapleton & West, 2012 ).

The most common self-reported reasons for smoking are stress relief and enjoyment, with around half of smokers reporting these smoking motives. Weight control, aiding concentration and socialising are also quite commonly cited (Fidler & West, 2009 ). Smoking for supposed stress relief, improved concentration, weight control or other functions has not been found to be related to attempts to stop or success of attempts to stop (Fidler & West, 2009 ). Smokers who report enjoying smoking are less likely to try to stop but not less likely to succeed if they do try (Fidler & West, 2011 ). In addition, having a positive smoker identity (liking being a smoker) predicts not trying to quit, over and above enjoyment of smoking (Fidler & West, 2009 ).

No clear association has been found between the number of times smokers have tried to stop in the past and their chances of success the next time they try (Vangeli et al., 2011 ). However, having tried to stop in the past few months is predictive of failure of the next quit attempt (Zhou et al., 2009 ). Belief in the harm caused by smoking is predictive of smokers making quit attempts but not the success of those attempts (Vangeli et al., 2011 ).

Some clinical studies have found that women were less likely to succeed in quit attempts than men but large population studies have found no difference in success rates between the genders (Vangeli et al., 2011 ) so it may be the case that women who seek help with stopping have greater difficulty than men who seek help with stopping.

Number of cigarettes smoked per day, time between waking and the first cigarette of the day and rated strength of urges to smoke prior to a quit attempt have been found to predict success of quit attempts (Vangeli et al., 2011 ).

Quit attempts that involve gradual reduction are less likely to succeed than those that involve quitting abruptly, even after controlling statistically for measures of cigarette addiction, confidence in quitting, other methods used to quit (e.g. nicotine replacement therapy) and sociodemographic factors (Lindson-Hawley et al., 2016 ).

Interventions to combat smoking

There is extensive evidence on interventions that can reduce smoking prevalence, either by reducing initiation or promoting cessation. Table ​ Table3 3 lists those that have the strongest evidence.

Population-level interventions

Increasing the financial cost of smoking through tax increases and control of illicit supply on average reduces overall consumption with a typical price elasticity globally of 0.4 (meaning that for every 10% increase in the real cost there is a 4% decrease in the number of cigarettes purchased). Most of the effect is in getting smokers to reduce their daily cigarette consumption so the effect on smoking prevalence has been found to be an average of a 1–2 percentage point prevalence reduction for every 10% increase in the real cost (Levy, Huang, Havumaki, & Meza, 2016 ). It has been claimed that increasing taxes on tobacco increases the amount of smuggling of cheap tobacco, but the evidence does not support this (Action on Smoking and Health, 2015a ; Joossens & Raw, 2003 ).

Social marketing campaigns (e.g. TV advertising) can prevent smoking uptake, increase the rate at which smokers try to quit and improve the chances of success. This can lead to a reduction in smoking prevalence. Their effectiveness varies considerably with intensity, type of campaign and context (Bala, Strzeszynski, Topor-Madry, & Cahill, 2013 ; Hoffman & Tan, 2015 ).

Legislating to ban smoking in all indoor public areas may have a one-off effect on reducing smoking prevalence but findings are inconsistent across different countries (Bala et al., 2013 ). For example, in countries such as France it was not possible to detect an effect while in England, there did appear to be a decline in prevalence following the ban.

Although it is hard to show conclusively, circumstantial evidence suggests that banning tobacco advertising and putting large graphic health warnings on cigarette packets may have reduced smoking prevalence in some countries (Hoffman & Tan, 2015 ; Noar et al., 2016 ).

Individual-level interventions to promote smoking cessation

Brief advice.

Brief advice to stop smoking from a physician and offer of support to all smokers, regardless of motivation to quit, has been found in randomised trials to increase rate of quitting by an average of 2 percentage points of all those receiving it, whether or not they were initially interested in quitting (Stead et al., 2013 ). The offer of support appears to be more effective in getting smokers to try to quit than just advising smokers to stop (Aveyard, Begh, Parsons, & West, 2012 ).

Pharmacotherapy

Using a form of nicotine replacement therapy (NRT: transdermal patch, chewing gum, nasal spray, mouth spray, lozenge, inhalator, dissolvable strip) for at least 6 weeks from the start of a quit attempt increases the chances of long-term success of that quit attempt by about 3–7 percentage points if the user is under the care of a health professional or provided as part of a structured support programme (Stead et al., 2012 ). Some studies have found that NRT when bought from a shop and used without any additional structured support does not improve the chances of success at stopping (Kotz, Brown, & West, 2014a , 2014b ). A small proportion of people who use NRT to stop smoking continue to use it for months or even years after stopping smoking, but NRT appears to carry minimal risk to long-term users (Royal College of Physicians, 2016 ; Stead et al., 2012 ).

Data are sparse but at present, using an electronic cigarette in a quit attempt appears to increase the chances of success at stopping on average by an amount broadly similar to that from NRT; the variety of products available and the greater similarity to smoking appear to make them more attractive to many smokers as a means of stopping than NRT (McNeill et al., 2015 ; Royal College of Physicians, 2016 ). Electronic cigarettes deliver nicotine to users by heating a liquid containing nicotine, propylene glycol or glycerol and usually flavourings to create a vapour that is inhaled. They appear to carry minimal acute risk to users. If they are used long-term, their risk is almost certainly much less than that of smoking (based on concentrations of chemicals in the vapour) (McNeill et al., 2015 ; Royal College of Physicians, 2016 ).

‘Dual-form NRT’ (combining a transdermal NRT patch and one of the other forms) increases the chances of success at stopping more than ‘single-form NRT’ (just using one of the products) (Stead et al., 2012 ). Starting to use a nicotine transdermal patch several weeks before the target quit date may improve the chances of success at quitting compared with starting on the quit date (Stead et al., 2012 ).

Taking the prescription anti-depressant, bupropion (brand name Zyban), improves the chances of success of quit attempts by a similar amount to single-form NRT (Hughes, Stead, Hartmann-Boyce, Cahill, & Lancaster, 2014 ). Bupropion often leads to sleep disturbance and carries a very small risk of seizure. Bupropion probably works by reducing urges to smoke rather than any effect on depressed mood, but how it does this is not known. It is contra-indicated in pregnant smokers and people with an elevated seizure risk or history of eating disorder (Hughes et al, 2014 ). Taking the tricyclic anti-depressant, nortriptyline also improves the chances of success of quit attempts, probably by about the same amount as bupropion and NRT (Hughes et al., 2014 ). Its mechanism of action is not known. Nortriptyline often leads to dry mouth and sleep disorder and can be fatal in overdose (Hughes et al., 2014 ).

Taking the nicotinic-acetylcholine receptor partial agonist, varenicline (brand name Chantix in the US and Champix elsewhere), improves the chances of success by about 50% more than bupropion or single-form NRT (Cahill, Lindson-Hawley, Thomas, Fanshawe, & Lancaster, 2016 ). This is true for smokers with or without a psychiatric disorder (Anthenelli et al., 2016 ). Varenicline appears to work both by reducing urges to smoke and the rewarding effect of nicotine should a lapse occur (West, Baker, Cappelleri, & Bushmakin, 2008 ). Varenicline often leads to sleep disturbance and nausea. Serious neuropsychiatric and cardiovascular adverse reactions have been reported, but in comparative studies these have not been found to be more common than placebo or NRT (Anthenelli et al., 2016 ; Cahill et al., 2016 ; Sterling, Windle, Filion, Touma, & Eisenberg, 2016 ).

Taking the nicotinic-acetylcholine receptor partial agonist, cytisine, appears to improve the chances of success at least as much as single-form NRT and probably more (Cahill et al., 2016 ). Cytisine often causes nausea. No serious adverse reactions have been reported to date (Cahill et al., 2016 ). Where it is licensed for sale, cytisine is less than 1/10th the cost of other smoking cessation medications (Cahill et al., 2016 ).

Behavioural support

There is good evidence that behavioural interventions of many kinds, delivered though several modalities can help smokers to stop. Thus, behavioural support (encouragement, advice and discussion) from a trained stop-smoking specialist, provided at least weekly until at least 4 weeks following the target quit date can increase the chances of long-term success of a quit attempt by about 3–7 percentage points, whether it is given by phone or face-to-face (Lancaster & Stead, 2005 ). Group behavioural support (specialist-led groups of smokers stopping together and engaging in a structured discussion about their experiences), involving at least weekly sessions lasting until at least 4 weeks after the target quit date can increase the chances of success of a quit attempt by a similar amount or possibly more than individual support (Stead & Lancaster, 2005 ). Scheduled, multi-session telephone support can improve rates of success at stopping smoking by a broadly similar amount (Stead, Hartmann-Boyce, Perera, & Lancaster, 2013 ) but some large studies have failed to detect an effect so contextual factors and/or the precise type of support could be crucial to success. The effects of behavioural support and medication/NRT on success at stopping smoking appear to combine roughly additively (Stead, Koilpillai, & Lancaster, 2015 ). Smoking cessation support appears to be effective in primary care, secondary care and worksite settings (Cahill & Lancaster, 2014 ; West et al., 2015 ). Financial incentives, in the form of vouchers, have been found to increase smoking cessation rates for as long as they are in place (Cahill, Hartmann-Boyce, & Perera, 2015 ; Higgins & Solomon, 2016 ). Printed self-help materials can improve the chances of success at stopping long term by around 1–2 percentage points (Hartmann-Boyce, Lancaster, & Stead, 2014 ).

There is still relatively limited evidence on the effectiveness of digital support interventions for smoking cessation. Thus, while there is evidence that tailored, interactive websites can improve the chances of success at stopping smoking compared with no support, brief written materials or static information websites, many of those tested have not been found to be effective and it is not clear what differentiates those that are effective from those that are not (Graham et al., 2016 ). Text messaging programmes have been found to increase the chances of success of quit attempts by about 2–7 percentage points (Whittaker, McRobbie, Bullen, Rodgers, & Gu, 2016 ). There is currently insufficient evidence to know whether smartphone applications can improve success rates of quit attempts, although preliminary data suggest that they might (Whittaker et al., 2016 ). Evidence on alternative and complementary therapies is not sufficient to make confident statements about their effectiveness as aids to smoking cessation (Barnes et al., 2010 ; White, Rampes, Liu, Stead, & Campbell, 2014 ).

Overall, the highest smoking cessation rates appear to be achieved using specialist face-to-face behavioural support together with either varenicline or dual form NRT. With this support, continuous abstinence rates up to 52 weeks, verified by expired-air carbon monoxide tests, of more than 40% have been achieved (Kralikova et al., 2013 ). More commonly, 52-week continuous abstinence rates with this treatment are between 15 and 25% (West et al., 2015 ).

Smoking cessation support for pregnant smokers

In pregnant smokers, there is some evidence that NRT can help promote smoking cessation but evidence for an effect sustained to end of pregnancy is not conclusive (Sterling et al., 2016 ). There is also evidence that written self-help materials and face-to-face behavioural support can aid smoking cessation (Jones, Lewis, Parrott, Wormall, & Coleman, 2016 ), and financial incentives have also been found to improve quitting rates among pregnant smokers (Tappin et al., 2015 ). Almost half of women who stop smoking during pregnancy as a result of a clinical intervention relapse to smoking within 6 months of the birth (Jones et al., 2016 ).

Effectiveness of programmes to reduce smoking uptake

School-based programmes that involve both social competence training and peer-led social influence have been found to reduce smoking uptake (Georgie, Sean, Deborah, Matthew, & Rona, 2016 ) but educational programmes have not (Thomas, McLellan, & Perera, 2013 ). Mass media campaigns and increasing the financial cost of smoking reduce smoking uptake (Brinn, Carson, Esterman, Chang, & Smith, 2012 ; van Hasselt et al., 2015 ).

Reducing the harm from tobacco and nicotine use

Smokers who report that they are reducing their cigarette consumption smoke only 1–2 fewer cigarettes per day on average than when they say they are not (Beard et al., 2013 ). Clinical trials have found that use of NRT while smoking can substantially reduce cigarette consumption compared with placebo (Royal College of Physicians, 2016 ) but national surveys show very little reduction in cigarette consumption when smokers take up use of NRT in real-world settings (Beard et al., 2013 ). The benefit from using NRT while continuing to smoke appears to be in promoting subsequent smoking cessation. Using NRT (or varenicline) to reduce cigarette smoking with no immediate plans to quit leads to increased rates of quitting subsequently (Wu, Sun, He, & Zeng, 2015 ).

‘Snus’, a form of tobacco that is placed between the gums and the cheek and which is prepared in a way that is very low in carcinogens, gives high doses of nicotine but without evidence of an increase in risk of major tobacco-related cancers and either no, or a small, increase in risk of heart disease. It does appear to increase risk of periodontal disease, however. Snus is very popular in Sweden. Sweden has very low rates of smoking and tobacco-related disease indicating that a form of nicotine intake other than smoking can become popular and suggesting that this can contribute to a substantial reduction in tobacco-related harm (Royal College of Physicians, 2016 ).

The introduction of complete bans on smoking in indoor public areas can also be considered as a harm reduction measure. In this case, the main issue is harm to non-tobacco users. The evidence shows that such bans have been rapidly followed in the UK and several other jurisdictions by a reduction in heart attacks in non-smokers (Action on Smoking and Health, 2014a ).

Conclusions

Tobacco smoking causes death and disability on a huge scale and only about half of smokers report enjoying it. Despite this, approximately 1 billion adults engage in this behaviour worldwide and only around 5% of unaided quit attempts succeed for 6 months or more. The main reason appears to be that cigarettes deliver nicotine rapidly to the brain in a form that is convenient, and palatable. Nicotine acts on the brain to create urges to smoke in situations where smoking would normally occur and when brain nicotine levels become depleted. Concern about the harm from, and financial cost of, smoking are mostly not sufficient to counter this.

Governments can reduce smoking prevalence by raising the cost of smoking through taxation, mounting sustained social marketing campaigns, ensuring that health professionals routinely advise smokers to stop and offer support for quitting, and make available pharmacological and behavioural support for stopping.

Statement of competing interests

RW has, within the past 3 years, undertaken research and consultancy for companies that develop and manufacture smoking cessation medications (Pfizer, GSK, and J&J). He is an unpaid advisor to the UK’s National Centre for Smoking cessation and Training. His salary is funded by Cancer Research UK.

Disclosure statement

No potential conflict of interest was reported by the author.

This work was supported by Cancer Research UK [grant number C1417/A22962].

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