Health effects of smoking and second-hand smoke
Tobacco use (commercial tobacco) is the leading preventable cause of premature death and diseases in Canada.
Indigenous peoples have been using tobacco traditionally for thousands of years. To many First Nations and some Métis communities in Canada, tobacco is considered sacred. Sacred tobacco is harvested and used differently than commercial tobacco (such as cigarettes, cigars and chewing tobacco).
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Health risks of tobacco use
Tobacco use can cause disease and other serious health outcomes, including cancer, respiratory ailments, and heart disease. People who smoke and anyone exposed to second-hand smoke are at risk.
Chemicals
Tobacco smoke contains over 7000 chemicals, of which over 70 are known to cause cancer. Tobacco leaves naturally contain some of these chemicals.
Burning a tobacco product like a cigarette, cigar, or pipe releases most of the other chemicals, including:
- tar
- benzene
- formaldehyde
- carbon monoxide
- hydrogen cyanide
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Diseases and conditions
Lung cancer
Lung cancer is the leading cause of death due to cancer in Canada. Smoking tobacco is the single most important preventable cause of lung cancer. Tobacco smoke causes genetic changes in the cells of the lungs that can lead to the development of lung cancer.
Other cancers
Research shows that smoking tobacco can lead to:
- leukemia
- respiratory and upper digestive tract cancers, particularly cancer of the:
- mouth
- esophagus
- throat (pharynx)
- voice box (larynx)
- cancers of the:
Respiratory diseases
The respiratory diseases associated with smoking are often grouped together and referred to as Chronic Obstructive Pulmonary Disease (COPD). COPD includes emphysema and chronic bronchitis.
Cigarette smoking can also increase the risk of respiratory symptoms, including:
- phlegm
- coughing
- wheezing
- difficult or laboured breathing (dyspnea)
Cardiovascular diseases
Cardiovascular diseases are diseases and injuries of the heart, the blood vessels of the heart, and the system of blood vessels (veins and arteries) in the body and brain.
Cardiovascular diseases caused by smoking include:
- heart attacks
- angina (coronary heart diseases)
- strokes (cerebrovascular diseases)
- blockages in the legs (peripheral vascular disease)
Information on other smoking-related diseases:
- Tobacco and Peripheral Vascular Disease
- Tobacco and Type 2 Diabetes
- Premature death
- Smoking and age-related macular degeneration
- Tobacco and impotence
- The visible health consequences of smoking
Benefits of quitting
Beyond improving your overall health and wellbeing, there are also social and environmental benefits to quitting smoking. Learn about more the Benefits to quitting.