Women who stop smoking by age 30 will enjoy huge health benefits and add about 10 years to their life, according to a new study. Those who quit by age 30 still lose roughly a month, and 40-year-olds lose about a year, but smoking into middle age is particularly deadly—even for those who don't light up often, the BBC reports. "Stopping works, amazingly well actually," says Sir Richard Peto, lead researcher of the Oxford study. "Smoking kills, stopping works, and the earlier you stop the better."
The study looked at 1.2 million women who picked up smoking in the 1950s and 60s—the first generation to smoke as much as men. Only now can researchers observe the long-term effects of smoking on women, which, it turns out, are the same as on men. But experts say the study doesn't give women license to puff away in their 20s, for smoking can still age skin prematurely and affect fertility and pregnancy. "The best thing for your health is to avoid smoking at all," says the head of the British Lung Foundation.