For all of you out there who might be trying to quit smoking, a massive new study headed by researchers with the American Cancer Society, the National Cancer Institute and others brings some encouraging news: If you quit by by 40, you can avoid the worst of what is in store.
In a retrospective study, the scientists tried to isolate the effects of smoking on hundreds of thousands of people whose health has been tracked for some time over a fifty year window. What they found was that, though a lifetime of smoking will “cut at least 10 years” off your life, if you quit by the time you’re 40 then pretty much all of this damage will be avoided. Really, they found that quitting at any point is way, way better for your health than not quitting or than simply cutting down. But kicking the butt by 40 means that “nearly all the excess risk can be avoided.”
It is not, however, says the CBC, a magic switch : “The researchers cautioned it is not safe to smoke until 40 and then stop because the risk is still substantial.”
Most of the gains in life expectancy come because the twin risks of heart disease and stroke quickly drop after smoking ends. Both diseases occur as the byproducts of tobacco smoke trigger clotting in the arteries, a process that can rapidly reverse.
Damage to the lungs, meanwhile, takes longer to heal. “The risk for lung cancer doesn’t disappear and the risk of respiratory disease doesn’t disappear” in former smokers, said Jha. “But the acute risk for heart attack or stroke pretty much disappears.”
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