During a nine-year study, researchers showed that older adults whose diets were high in folate reduced their risk of Alzheimer's disease by half compared with those whose diets contain less than the Recommended Dietary Allowances (RDA).
The study appears in the inaugural issue of Alzheimer's and Dementia: the Journal of the Alzheimer's Association.
Alzheimer's disease is a progressive brain disorder that gradually destroys memory and the ability to think and reason. An estimated 4 million people in the U.S. have dementia, most with Alzheimer's disease. By 2050, that number could be as high as 16 million, according to the Alzheimer's Association.
More Folate Needed
Using information gathered from the Baltimore Longitudinal Study of Aging, researchers identified the relationship between diet and Alzheimer's disease risk.
They analyzed the diets of 579 volunteers (359 men, 220 women) 60 and older without Alzheimer's disease and followed them for nine years. The researchers looked at what percentage of participants' diets contained antioxidant vitamins (E, C, carotenoids) and B vitamins (folate, B-6, and B-12).
Between 1984 and 1991, participants provided diaries describing their diet during a typical week. Total daily nutrient intake was estimated as the combined intake from diet and supplements.
Healthy Diet Important
Folate has also been shown to lower blood levels of homocysteine, a risk factor for heart disease. High homocysteine levels, as well as decreased folate and vitamin B-12 levels, have also been associated with stroke and Alzheimer's disease.