The women who quit smoking can get to their normal health within five years, but it can take decades to repair respiratory damage and ward off the risks of lung cancer, articulated a study released on Tuesday.

According to the study published in the May 7 issue of theJournal of the American Medical Association, the women who quit smoking have a 21 % lower risk of dying from coronary heart disease within five years of blowing out their last cigarette. The risks of dying from other conditions also decline after quitting, but it takes much more time to get normal.

The study found that those who stopped had a 13 percent reduction in the risk of death from all causes, including heart and vascular problems, within the first five years, and after 20 years, the risk of death from any cause was the same for those who quit as for those who had never smoked.

The study articulated that for deaths due specifically to respiratory diseases, there was an 18 percent reduction within 5 to 10 years of quitting, reaching the level found in nonsmokers after 20 years. But while there was a 21 percent reduction in the risk of lung cancer death within five years, it took 30 years for that excess risk to disappear.

Study author Stacey Kenfield, "The harms of smoking are reversible and can decline to the level of nonsmokers. For some conditions like chronic obstructive pulmonary disease, it can take more than 20 years, but there is a rapid reduction for others."

Kenfield, who is a postdoctoral research fellow in the department of epidemiology at the Harvard School of Public Health in Boston, said, "It's never too early to stop, and it's never too late to stop smoking.”
 
“Our findings indicate that 64 percent of deaths in current smokers and 28 percent of deaths in past smokers are attributable to smoking. Quitting reduces the excess mortality rates for all major causes of death examined,” said the researchers.