Smoking here refers to cigarette smoking. Smoking other hard drugs is not considered here. Cigarette contain about 330 active chemicals including arsenic, hydrogen sulphide, acids, and lead used in paints. Irrespective of the amount smoked, the health issues remain the same, that is someone who smokes 2 cigarettes a day or another who smokes 20 cigarettes a day or unfortunately prolonged exposure to second hand smoke seems to carry the same health risks from latest research.

Smoking causes lung disease, asthma, emphysema, high BP, cancers, diabetes, and psychological problems. Children exposed to second hand smoke suffer more lung and ear infections that others.

Giving up smoking add up to 10 years to life expectancy of an individual.