When a smoker stops smoking:
In 8 hours, their oxygen level is back to normal.
In 24 hours, their risk of having a heart attack has decreased.
In 2 weeks, lung function has improved 30 percent.
In 10 years, the risk of having a stroke decreases by 50%.
In 10 years, the risk of lung cancer has decreased to the same as non-smokers!
Normal Lungs: Smoker’s Lungs: