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Alzheimer's Disease and the Environment

Recent studies have shown that genetics is hardly the only factor that determines who develops Alzheimer's disease and who does not. But CBS Correspondent Cynthia Bowers takes a closer look at some findings no one expected--findings that send a clear message to older Americans.

It was a finding that surprised even the scientists. After studying two groups living on different continents, researchers found that African Americans are twice as likely to develop Alzheimer's as genetically similar black Nigerians.

"You would think that with all of the public health problems and nutritional problems and everything else in Nigeria you would expect to find rates of illness, any illness, a little higher," says Dr. Hugh Hendrie of Indiana University.

But that wasn't the case at all. Not only were the Nigerians less likely to develop any form of dementia: They also had lower cholesterol, lower blood pressure, and lower rates of hypertension and diabetes as well.

This study, which tracked blacks in Indianapolis and members of the Yoruba tribe in Nigeria for 10 years, strongly suggests its not just your genes, but how you live that can trigger the disease. The Yoruba eat mainly vegetables and live in a poor area that promotes exercise. Researchers feel the way the Yoruba live their lives may play a key role in their ability to avoid Alzheimer's.

"It's going to be a genetic environmental interaction we're sure, but I think it confirms we're on the right track and we should look for some sort of combination of factors," says Hendrie.

Eighty-one-year-old Evelyn Mason of Indianapolis, who was one of the participants, takes heart from the results. She eats well and keeps both her brain and body active.

"I say now, What would I do in case I have a case of Alzheimer's and it progressed?" asks Mason. "What would happen? That's why I fight so hard. That's why I see it as a challenge--that I have a part to play, too. I'm going to play my part to the nth degree."

Even so she still worries about Alzheimer's everyday, but 81-year-old Ethel Germany lives with it, and so does her daughter.

"It needs to be researched, it needs to be addressed. The African-American community needs to be aware: This is not a taboo, this is not a personal issue, this is everybody's," says Karen Jackson.

Doctors here say they feel they are racing the clock trying to isolate the cause and find a cure. By the middle of this century, 14 million Americans will be diagnosed with Alzheimer's, and for them time is running out.

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