answer:The Lung Association has a very cool little chart about this.. Reposted below: Benefits When smokers quit, within twenty minutes of smoking that last cigarette the body begins a series of changes. At 20 minutes after quitting: * blood pressure decreases * pulse rate drops * body temperature of hands and feet increases At 8 hours: * carbon monoxide level in blood drops to normal * oxygen level in blood increases to normal At 24 hours: * chance of a heart attack decreases At 48 hours: * nerve endings start regrowing * ability to smell and taste is enhanced The first year after quitting: At 2 weeks to 3 months: * circulation improves * walking becomes easier * lung function increases 1 to 9 months: * coughing, sinus congestion, fatigue, shortness of breath decreases 1 year: * excess risk of coronary heart disease is decreased to half that of a smoker Long-term Benefits of Quitting At 5 years: * from 5 to 15 years after quitting, stroke risk is reduced to that of people who have never smoked. At 10 years: * risk of lung cancer drops to as little as one-half that of continuing smokers * risk of cancer of the mouth, throat, esophagus, bladder, kidney, and pancreas decreases * risk of ulcer decreases At 15 years: * risk of coronary heart disease is now similar to that of people who have never smoked * risk of death returns to nearly the level of people who have never smoked