If you happen to be a smoker, the best thing you can do for your heart is stop. People who smoke are up to 6 times more likely to suffer a heart attack than nonsmokers. The risk of heart attack increases with the number of cigarettes smoked each day.
The good news is that quitting smoking will immediately begin to reduce your risk, and the benefit in reduced risk will continue to increase over time. Just one year after you stop smoking, your risk will have dropped by more than half.