Whether you're a smoker or not, you probably know it can harm your body. But you might not know that smoking can cause cancer and other diseases. Emphysema Among the many effects of smoking on the body is damage to the lungs. When cigarette smoke enters the lungs, it damages the cilia, the cells that clean the airways. This leads to an obstruction in the flow of oxygen and carbon dioxide and makes it difficult for the lungs to breathe. The alveoli, or minor, thin-walled air sacs, are also damaged. These air sacs lose their ability to expand and contract. This shrinking of the alveoli forces carbon dioxide out of the body. When they cannot grow, the air sacs become thick and swollen and impede breathing. Heart disease Compared to non-smokers, smoking increases heart attack and stroke risk. Cigarette smoke contains 4,000 chemicals, some of which are carcinogens. They damage the cells that line the heart, blood vessels, and other organs. Several studies have outlined the relationship...