Two studies on smoking and mortality published this week in the New England Journal of Medicine have shown that quitting smoking helped to reduce the risk of death associated with smoking.

One study was led by Dr. Prabhat Jha of the Center for Global Health Research inToronto, while the other study was led by Michael J. Thun of the American Cancer Society.

Smokers lose at least one decade of life expectancy over nonsmokers on average.

Those who kick the habit before age 40 reduce the excess risk of death associated with continued smoking by about 90%.

Women are now as likely to die from smoking-related illnesses as men. In the early 1960s, women smokers were 2.73 times more likely to die from lung cancer than their nonsmoking counterparts; by 2010, they were 25.66 times more likely to die of the disease.