The studies, found that people with the greatest exposure to second-hand smoke were twice as likely to develop Alzheimer's compared with those who had very little exposure.
"Very disturbing because we can control whether or not we smoke, but we can't always control the second-hand smoke we're going to inhale," says Dr. John Swartzberg, head of the editorial board at the U.C. Berkeley Wellness Letter.
"We know it increases your chance for a heart attack, and there's good data that it increases your chance for a stroke. And that's all talking about the effects of second-hand smoke on your blood vessels. So, the thinking is that this may be very much the case with Alzheimer's disease as well. But there are other causes of dementia and many of those have a relationship to our vascular supply. So, second-hand smoke certainly plays a role with that."
More Information: Secondhand Smoke Boosts Risk for Alzheimer's