JAMA patient page. Smoking cessation.

Tobacco smoking has devastating effects on health. The smoke damages the lungs, resulting in a diminished ability of oxygen to enter the body. Smoke long enough and eventually you will get emphysema. Various chemicals in smoke enhance the development of atherosclerosis (hardening of the arteries), leading to strokes and heart attacks. One of tobacco’s chemicals, nicotine, acts directly on the brain, causing an addiction to smoking. Smoking is related to a number of cancers. If you smoke, you have a 50% chance of dying from a smoking-related complication and will live 10 fewer years than if you did not smoke. Despite these risks, 20% of all adult Americans smoke.