Smoking causes cancer, lung disease and cardiovascular disease. In Southeast Asia, people have chewed betel nut for centuries. As it provides a stimulant effect, it stains their teeth and causes cancer. Alcohol is consumed worldwide for its ability to relax inhibitions and improve mood. In the United States alone, drunk driving causes tens of thousands of deaths every year.
Alcohol abuse destroys livers.
A huge percentage of Americans are obese. Their lifestyle choices put them at risk of diabetes and heart disease. A McDonald's Big Mac is tasty. Eat enough of them, and your arteries will become clogged with fat. It's a risky pleasure.