Brain-Healthy Diets

Eating certain foods could sharply lower your odds of developing Alzheimer’s disease.


A GROWING BODY OF RESEARCH suggests that a diet rich in the nutrients found in vege- tables, whole grains, beans, nuts, vegetable oils and fish could help lower the risk of developing Alzheimer’s disease.

Two diets show promising results, based on studies that show links between people’s diets and brain health. The CANADIAN BRAIN HEALTH FOOD GUIDE, created
by scientists in Toronto, is associated with a 36% re- duction in the risk of devel- oping Alzheimer’s disease. The MIND DIET, which comes from experts at Rush Uni- versity Medical Center in Chicago and the Harvard T.H. Chan School of Public Health, lowered the risk
of Alzheimer’s by 53%. Re- searchers will launch clini- cal trials to study both diets this year.

It’s not yet well under- stood how nutrition affects the brains of older adults. But a poor diet can increase the risk of developing hy- pertension, cardiovascular disease, obesity and diabe- tes, which can compromise an individual’s cognitive function. A good diet that reduces the risk of chronic illness is beneficial to the brain. Also, what people eat appears to influence brain cells and how they function.

Foods that help the aging brain. The diets differ in several respects, reflecting varying interpretations of research regarding nutri- tion’s impact on the aging brain. The MIND diet rec- ommends two servings of vegetables and at least three servings of whole grains every day, plus five half-cup portions of berries and one serving of seafood each week. The Canadian diet calls for five servings of veg- etables and four servings of fruit each day and suggests that seafood be eaten three times a week (it doesn’t make a specific recommen- dation for whole grains).

Martha Clare Morris, a nutritional epidemiologist at Rush University Medical


Center and originator of the MIND diet, says several nu- trients have been shown to have biological mechanisms critical to brain health. One is vitamin E, a powerful an- tioxidant found in oils, nuts, seeds, whole grains and leafy green vegetables. It’s associated with slower cog- nitive decline, a lower risk of dementia and reduced accumulation of beta amy- loid proteins—a culprit in Alzheimer’s disease.

Also on her to-eat list
is vitamin B12—found in meat, eggs, cheese and fish—and vitamin B9 (fo- late), found in green leafy vegetables, grains, nuts and beans. Aging affects stom- ach acids that assist in the absorption of B12. A deficiency can lead to confusion and memory problems, while folate deficiency is associated with cognitive decline and an increased risk of dementia.

Omega-3 fatty acids (found in fish and nut oils), especially DHA (docosa- hexaenoic acid), are highly concentrated in the brain, where they are incorpo- rated in cell membranes and play a role in the trans- mission of signals between cells. Because maintaining healthy blood vessels to the brain is so important, brain health recommendations are similar in many ways to heart health recommenda- tions, says Carol Green- wood, professor of nutrition at the University of Toronto and a key force behind the Canadian diet.

Foods to avoid. For the most part, the Canadian and MIND diets concur
on the types of foods you should avoid or limit to once a week: sweets, butter, red meat, fried and processed foods, and saturated fats, found in pastries.

Studies promoting the cognitive benefits of drink- ing tea or eating blueberries have garnered headlines, but what really matters is dietary patterns and the ways components of various foods interact to promote brain health. The bottom line: Concentrate on eating an assortment of foods that are good for you.