Eating a group of specific foods — known as the MIND diet — may slow cognitive decline among aging adults, even when the person is not at risk of developing Alzheimer’s disease, according to researchers at Rush University Medical Center.
This finding supplements a previous study by the research team, reported by KurzweiliAI in March, that found that the MIND diet may reduce a person’s risk in developing Alzheimer’s disease.
The researchers’ new study shows that older adults who followed the MIND diet more rigorously showed an equivalent of being 7.5 years younger cognitively than those who followed the diet least. Results of the study were recently published online in the journal Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.
So what is the MIND diet?
The MIND diet, which is short for “Mediterranean-DASH Diet Intervention for Neurodegenerative Delay,” was developed by Martha Clare Morris, ScD, a nutritional epidemiologist, and her colleagues. As the name suggests, the MIND diet is a hybrid of the Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets. Both have been found to reduce the risk of cardiovascular conditions, like hypertension, heart attack and stroke.
“Everyone experiences decline with aging; and Alzheimer’s disease is now the sixth leading cause of death in the U.S., which accounts for 60 to 80 percent of dementia cases. Therefore, prevention of cognitive decline, the defining feature of dementia, is now more important than ever,” Morris says. “Delaying dementia’s onset by just five years can reduce the cost and prevalence by nearly half.”
The MIND diet has 15 dietary components, including 10 “brain-healthy food groups” and five “unhealthy groups” to avoid — red meat, butter and stick margarine, cheese, pastries and sweets, and fried or fast food.
To adhere to and benefit from the MIND diet, a person would need to eat at least three servings of whole grains, a green leafy vegetable and one other vegetable every day — along with a glass of wine (or red-grape juice) — snack most days on nuts, have beans every other day or so, eat poultry and berries at least twice a week and fish at least once a week.
In addition, the study found that to have a real shot at avoiding the devastating effects of cognitive decline, he or she must limit intake of the designated unhealthy foods, especially butter (less than 1 tablespoon a day), sweets and pastries, whole fat cheese, and fried or fast food (less than a serving a week for any of the three).
Berries are the only fruit specifically to be included in the MIND diet. “Blueberries are one of the more potent foods in terms of protecting the brain,” Morris says, and strawberries also have performed well in past studies of the effect of food on cognitive function.
The National Institute of Aging-funded study evaluated cognitive change over a period of 4.7 years among 960 older adults who were free of dementia on enrollment. Averaging 81.4 years in age, the study participants also were part of the Rush Memory and Aging Project, a study of residents of more than 40 retirement communities and senior public housing units in the Chicago area.
During the course of the study, they received annual, standardized testing for cognitive ability in five areas — episodic memory, working memory, semantic memory, visuospatial ability and perceptual speed. The study group also completed annual food frequency questionnaires, allowing the researchers to compare participants’ reported adherence to the MIND diet with changes in their cognitive abilities as measured by the tests.
Abstract of MIND diet slows cognitive decline with aging
Background: The Mediterranean and dash diets have been shown to slow cognitive decline; however, neither diet is specific to the nutrition literature on dementia prevention.
Methods: We devised the Mediterranean-Dietary Approach to Systolic Hypertension (DASH) diet intervention for neurodegenerative delay (MIND) diet score that specifically captures dietary components shown to be neuroprotective and related it to change in cognition over an average 4.7 years among 960 participants of the Memory and Aging Project.
Results: In adjusted mixed models, the MIND score was positively associated with slower decline in global cognitive score (β = 0.0092; P < .0001) and with each of five cognitive domains. The difference in decline rates for being in the top tertile of MIND diet scores versus the lowest was equivalent to being 7.5 years younger in age.
Conclusions: The study findings suggest that the MIND diet substantially slows cognitive decline with age. Replication of these findings in a dietary intervention trial would be required to verify its relevance to brain health.