The real reason to suggest that smokers stop smoking is because it can kill them (and others). Facts that every smoker knows but ignores anyways: [spoiler]"SUMMARY OF FINDINGS FROM SURGEON GENERAL’S REPORTS ON SMOKING AND HEALTH 1. There is no safe level of exposure to tobacco smoke. Any exposure to tobacco smoke—even an occasional cigarette or exposure to secondhand smoke—is harmful. 2. Damage from tobacco smoke is immediate. Tobacco smoke contains more than 7,000 chemicals and chemical compounds that reach your lungs every time you inhale. Your blood then carries the poisons to all parts of your body. These poisons damage DNA, which can lead to cancer; damage blood vessels and cause clotting, which can cause heart attacks and strokes; and damage the lungs, which can cause asthma attacks, emphysema, and chronic bronchitis. 3. Smoking longer means more damage. Both the risk and the severity of many diseases caused by smoking are directly related to how long the smoker has smoked and the number of cigarettes smoked per day. 4. Cigarettes are designed for addiction. The design and contents of tobacco products make them more attractive and addictive than ever before. Nicotine addiction keeps people smoking even when they want to quit. 5. Even low levels of exposure, including exposure to secondhand tobacco smoke, are dangerous. You don’t have to be a heavy smoker or a long-time smoker to get a smoking-related disease or have a heart attack or stroke triggered by smoke. 6. There is no safe cigarette."[/spoiler] Edit: A bit of humor to break the tension.