Heart problems

Smoking increases the chance of heart disease. Several ingredients of tobacco lead to the narrowing of blood vessels, increasing the likelihood of a blockage, and thus a heart attack or stroke. According to a study by an international team of researchers, people under 40 are five times more likely to have a heart attack if they smoke.

Other tobacco chemicals lead to high blood pressure. Also, some chemicals may damage the inside of arteries, for example making it possible for cholesterol to adhere to the artery wall, possibly leading to a heart attack.