A Major Threat to Health Smoking and health Smoking is the number one health hazard in the U.S. Smokers are much more likely to suffer crippling poor health as they get older than nonsmokers are.
Smokers also are more likely to die early.
In recent years, people have become ever more aware of the dangers of smoking. Only 1 adult in 4 in the U.S. now smokes, compared with 1 in 3 a few years ago. Studies have shown that even people who have smoked heavily benefit from quitting. Studies have also shown that breathing smoke from other people's cigarettes can be harmful. Smoking and cancer Cigarette smoking is the main cause of lung cancer.