20 Minutes After Quitting:

Your blood pressure drops to a level close to that before the last cigarette. The temperature of your hands and feet increases to normal.

8 Hours After Quitting:

The carbon monoxide level in your blood drops to normal.

24 hours After Quitting:

Your chance of heart attack decreases.

2 Weeks-3 Months After Quitting:

Your circulation improves and your lung function increases up to 30 percent.

1-9 Months After Quitting:

Coughing, sinus congestion, fatigue, and shortness of breath decreases; cilia (tiny hair-like structures that move mucus out of the lung) regain normal function in the lungs, increasing the ability to handle mucus, clean the lungs and reduce infection.

1 Year After Quitting:

The excess risk of coronary heart disease is half that of a smoker's.

5-15 Years After Quitting:

Your stroke risk is reduced to that of a nonsmoker 5-15 years after quitting.

10 Years After Quitting:

The lung cancer death rate is about half that of a continuing smoker's. The risk of cancer of the mouth, throat, espohagus, bladder, kidney and pancreas decreases.

15 Years After Quitting:

The risk of coronary heart disease is that of a nonsmoker's.

Source: American Cancer Society