Don’t smoke, and avoid secondhand smoke

The worst thing you can do for your health is to smoke. Smoking greatly increases the risk of heart attacks, strokes, respiratory diseases such as chronic obstructive pulmonary disease (COPD), and many types of cancer, including cancer of the lung, throat, mouth, colon, and bladder. No amount of smoking is safe—not even one cigarette a day. Breathing secondhand smoke also increases the risk of cardiovascular disease and cancer.

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