After less than 30 minutes of smoking your last cigarette:

• pulse returns to normal*
• blood pressure drops down to normal*
• temperature of hands and feet increase to normal*

After 8 hours:

• blood's oxygen level returns to normal*
• carbon monoxide level in blood decreases to normal*

After 24 hours:

• risk of heart attack decreases

After 48 hours:

• sense of smell and taste increase
• nerve endings begin regrowth

After 72 hours:

• breathing becomes easier after bronchial tubes relax
• lung capacity increases

After 2 weeks to 3 months:

• lung ability increases by as much as 30%
• circulation improves
• walking is easier

After 1 to 9 months:

• body's energy level increases
• sinus congestion, coughing, fatigue, shortness of breath decrease
• lungs increase their ability to handle mucus, reduce infection and clean themselves

After 5 years:

• death rate because of lung cancer decreases about 50% for the average, one-pack-a-day smoker

After 10 years:

• pre-cancerous cells are replaced
• death rate from lung cancer becomes about equal to that of non-smokers
• risks for other cancers (mouth, larynx, pancreas, bladder, kidney and esophagus) decrease*

"Normal" refers to what was an average level for you before smoking your last cigarette, depending on your fitness level and other factors.

The above information is provided by the American Cancer Society.