Most people know that smoking cigarettes can cause lung cancer. However, smoking is also a major risk factor for a heart attack. Substances in cigarette smoke not only reduce the amount of oxygen in the blood, but also promote the development of atherosclerosis and the formation of blood clots. Cigar and pipe smoking also increase the risk of heart attacks but not to the same degree as cigarette smoking, probably because cigar and pipe users are less likely to inhale.
If you smoke, your risk of having a heart attack is more than twice that of a nonsmoker, and you're more likely to have a fatal heart attack. No amount of smoking is safe. If you want to put the brakes on your risk, you need to stop smoking entirely. Fortunately, even after many years of a cigarette habit, you can return your risk of a heart attack to that of a nonsmoker within about five years of quitting, although the elevated risk of developing lung cancer persists.
If you are not a smoker, watch out for secondhand smoke. It also can contribute to heart attacks. In fact, cities that institute indoor smoking bans also see a decrease in the rate of hospital admissions for heart attacks.