Nicotine safe, helps in Alzheimer's, Parkinson's
Smoking, of course, damages the lungs and blood vessels, and contributes to an array of health problems, but nicotine — the calming chemical that cigarettes deliver — might actually be good for the aging brain.
Smokers, for example, are less likely to develop Alzheimer's disease — a phenomenon that has long puzzled scientists because smoking contributes to cardiovascular disease, which strongly increases the risk of Alzheimer's.
But closer investigation revealed that smoking doesn't confer the protection; nicotine does.
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