Individuals use tobacco in various forms all over the world for recreational purposes. However, users should be aware of the adverse effects of tobacco. Epidemiological research focuses primarily on cigarette tobacco smoking, which has been studied more extensively than any other form of consumption such as chewable tobacco and snuff. Globally, tobacco use is the single greatest cause of preventable death. According to the World Health Organization (WHO), tobacco causes more than 6 million deaths each year.

Tobacco smoke contains more than 7,000 chemicals, with 250 known to be harmful substances including tar, carbon monoxide, benzene, formaldehyde, and hydrogen cyanide. In addition, tobacco contains a highly addictive drug, nicotine. These chemicals cause tobacco to be an important risk factor for many diseases including the following:

• Heart disease: Cigarette smoking causes about one in every five deaths in the United States each year.
• Stroke: Approximately one-quarter of all strokes are in direct correlation with smoking tobacco. 
• Cancer: Research from the National Health Interview Survey and death certificate data from the National Center for Health Statistics proposed that smoking causes 30% of all cancer deaths. 
• Chronic obstructive pulmonary disease (COPD): The same survey found 80% of all chronic obstructive pulmonary disease deaths came from tobacco smoking.

Smokers tend to lose between 13 to 15 years of their lives if they do not choose to quit smoking. Each cigarette is calculated to shorten your life by 11 minutes. Non-smokers, both children and adults, can feel the adverse effects of tobacco through second-hand tobacco smoke generated by another person smoking. According to the Centers for Disease Control and Prevention (CDC), 2.5 million non-smokers have died from exposure to secondhand smoke since 1964.

Even third-hand smoking can cause detrimental effects where tobacco residue from clothing and surfaces are inhaled by an individual. Research presented at the 247th National Meeting and Exposition of the American Chemical Society advises that third-hand smoke damages DNA and may cause cancer. Another study from the University of California-Riverside suggested that third-hand smoke may be linked to liver, lung, and skin problems.

The probability of a person contracting a disease directly correlates with the length of time and with the amount smoked. Luckily, if someone chooses to stop smoking and stop being around smoke, their body begins to repair itself and the chances of getting a disease gradually reduces with time. After one year of quitting, the risk of contracting heart disease drops to half compared to a person who continues to smoke. Though, the risk varies depending on how long the former user smoked and the types of cigarettes smoked when they used the substance.

Smoking cessation can improve your quality of life. If you are looking for a way to feel rejuvenated, then talk to your doctor about ways to stop smoking safely to avoid smoking withdrawal and the negative effects of quitting smoking. 

Additional resources:

Danaei, G., Ding, E. L., Mozaffarian, D., Taylor, B., Rehm, J., Murray, C. J., & Ezzati, M. (2009). The preventable causes of death in the United States: comparative risk assessment of dietary, lifestyle, and metabolic risk factors.PLoS medicine, 6(4), e1000058.

Girot, M. (2009). Smoking and stroke. Presse Médicale, 38(7/8), 1120-1125.

Hang, B., Sarker, A. H., Havel, C., Saha, S., Hazra, T. K., Schick, S., ... & Gundel, L. A. (2013). Thirdhand smoke causes DNA damage in human cells.Mutagenesis, 28(4), 381-391.

Martins-Green, M., Adhami, N., Frankos, M., Valdez, M., Goodwin, B., Lyubovitsky, J., ... & Curras-Collazo, M. (2014). Cigarette smoke toxins deposited on surfaces: implications for human health. PloS one, 9(1), e86391.

National Toxicology Program. Report on Carcinogens. Eleventh Edition. U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program, 2005.

Shah, R. S., & Cole, J. W. (2010). Smoking and stroke: the more you smoke the more you stroke. Expert review of cardiovascular therapy, 8(7), 917-932.

U.S. Department of Health and Human Services. The Health Consequences of Smoking—50 Years of Progress: A Report of the Surgeon General. Atlanta: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014.

U.S. Department of Health and Human Services. How Tobacco Smoke Causes Disease: The Biology and Behavioral Basis for Smoking-Attributable Disease: A Report of the Surgeon General. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2010.

U.S. Department of Health and Human Services. The Health Consequences of Smoking: A Report of the Surgeon General. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2004.

Helpful Peer-Reviewed Medical Articles:

US Department of Health and Human Services. (2004). The health consequences of smoking: a report of the Surgeon General.

Hofhuis, W., De Jongste, J. C., & Merkus, P. J. F. M. (2003). Adverse health effects of prenatal and postnatal tobacco smoke exposure on children. Archives of disease in childhood, 88(12), 1086-1090.

US Department of Health and Human Services. (2006). The health consequences of involuntary exposure to tobacco smoke: a report of the Surgeon General. Atlanta, GA: US department of health and human services, centers for disease control and prevention, Coordinating center for health promotion, National center for chronic disease prevention and health promotion, Office on smoking and health, 709.

Satarug, S., & Moore, M. R. (2004). Adverse health effects of chronic exposure to low-level cadmium in foodstuffs and cigarette smoke. Environmental health perspectives, 1099-1103.

Mitchell, B. E., Sobel, H. L., & Alexander, M. H. (1999). The adverse health effects of tobacco and tobacco-related products. Primary Care: Clinics in Office Practice, 26(3), 463-498.