Researchers in the Netherlands have found that a diet rich in nuts, leafy green vegetables and other antioxidant-rich foods may reduce the risk of Alzheimer's disease.

"This and a number of important population studies have pointed to vitamin E as possibly protective against oxidative damage or other mechanisms associated with cognitive decline and dementia," said Neil Buckholtz, Ph.D., head of the Dementias of Aging Branch at the National Institute on Aging.

The Rotterdam Study, a population-based study, included 5395 participants, aged 55 or older at the beginning of the trial (1990-1993). All were dementia-free and non-institutionalized, with reliable dietary evaluations.

Participants were re-examined in 1993-1994 and again in 1997-1999, and consistently monitored for incident dementia. After an average six-year follow-up, 197 had developed dementia, including 146 who were diagnosed with Alzheimer's.

The researchers, reporting in The Journal of the American Medical Association, found a strong link between those with a high intake of vitamins C and E and a reduced risk of Alzheimer's. Likewise, smokers with a high intake of the antioxidants beta-carotene and flavonoids cut their risk of Alzheimer's as well.

But Buckholtz emphasized that researchers have not determined the safety, effectiveness and proper amounts needed of antioxidant supplements, and urged that high doses of vitamin E and other supplements not be taken until more is known about their effects.

"The only way this association can really be tested is through clinical studies and trials now underway. These will help us determine whether vitamin E in food or in supplements -- or taken together -- can prevent or slow down the development of mid cognitive impairment or Alzheimer's disease."

Other Sources: Journal of the American Medical Association, National Institute of Aging