October 15, 2021
New evidence supports the idea that what you eat can have benefits for brain health. The study found that eating a diet rich in leafy greens, whole grains and vegetables may help to preserve thinking and memory skills in old age, even for people at high risk for Alzheimer’s disease.
The findings come from researchers at Rush University Medical Center in Chicago, who followed 569 men and women for up to 16 years, beginning in 2004. All were part of the large and ongoing Rush Alzheimer’s Disease Center’s ongoing Memory and Aging Project, which includes people living in the Chicago area.
None of the study participants were known to have Alzheimer’s disease or other forms of dementia while alive. But all agreed to undergo annual clinical evaluations and, after they died, a brain autopsy to look for the telltale amyloid plaques and tau tangles (or neurofibrillary tangles) that are a hallmark of Alzheimer’s disease. It is important to note, however, that a good number of people have plaques and tangles in their brains but do not have serious memory problems that might lead to a diagnosis of Alzheimer’s.
Participants completed detailed food questionnaires about their typical diets, including how often they ate 144 specific food items the previous year. Foods were divided into 10 “brain healthy” food groups and 5 “brain unhealthy” food groups, according to the MIND Diet developed by researchers at Rush.
The MIND diet combines elements of two diets that have been shown to be beneficial for heart health: the traditional Mediterranean diet, rich in fruits, vegetables, whole grains, legumes and olive oil; and the DASH (Dietary Approaches to Stop Hypertension) diet, low in salt and also rich in vegetables, fruits, low-fat dairy and nuts. Previous studies have found that the MIND diet may reduce a person’s risk of developing Alzheimer’s disease and other forms of dementia.
To adhere to the MIND diet, a person would need to eat, for example, at least three servings of whole grains, leafy greens and a vegetable daily (a glass of wine would also be fine); have beans every other day or so; eat berries and poultry at least twice a week and fish once a week; and snack on foods like nuts (in moderation). Foods to be avoided or eaten less often would include red meat, saturated fats like butter (no more than one-and-a-half teaspoons a day) and stick margarine, sugary sweets and pastries, whole fat cheese, and fried or fast food.
Study participants were scored according to how closely they adhered to a MIND style diet over the course of the study, until the person died. Regardless of how many plaques and tangles they had in their brains, the MIND diet appeared to help protect them against developing serious memory and thinking problems.
“We found that a higher MIND diet score was associated with better memory and thinking skills, independently of Alzheimer’s disease pathology and other common age-related brain pathologies,” said Dr. Klodian Dhana, the study’s lead author and an Assistant Professor at Rush Medical College. “The diet seemed to have a protective capacity and may contribute to cognitive resilience in the elderly. There are fairly simple diet and lifestyle changes a person could make that may help to slow cognitive decline with aging and contribute to brain health.”
Previous research from Rush has suggested that following a brain-healthy MIND diet over many years may slow aging-related cognitive decline in healthy seniors by an average of seven-and-a-half years. While it might look difficult to adhere to such a diet all of the time, following it partially will already be better than eating few of these foods at all.
The findings add to growing evidence that what we eat can affect our brain health over the long term. A diet rich in leafy greens, whole grains and vegetables and moderate amounts of alcoholic drinks may help to keep memory sharp in old age, while diets heavy in red meat, butter, cheese, cakes and sweets, and fried or especially fast food may have the opposite effect, spurring memory decline.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Marc Flajolet, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Klodian Dhana, Bryan D. James, Puja Agarwal, et al: “MIND Diet, Common Brain Pathologies, and Cognition in Community-Dwelling Older Adults.” Journal of Alzheimer’s Disease, September 14, 2021. Rush University Medical Center.