The MIND diet combines elements of the Mediterranean and the DASH (Dietary Approaches to Stop Hypertension) diets.rostovtsevayulia/Getty Images
Research increasingly shows that everyday lifestyle choices, including diet, play an important role in preserving brain health as we age.
Studies suggest the MIND diet, for example, can slow cognitive decline and reduce the risk of Alzheimer’s disease. (MIND is short for Mediterranean-DASH Diet Intervention for Neurodegenerative Delay.)
Evidence connecting the healthy dietary pattern to long‑term changes in brain structure is sparse, but a new study published in the Journal of Neurology, Neurosurgery & Psychiatry strengthens the case for the MIND diet’s cognitive benefits.
Closer adherence was associated with slower progression of key brain structural changes that are widely recognized as markers of brain aging.
Here’s what to know about the research, plus a breakdown of the MIND diet.
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About the latest research
For the study, published March 17, participants were drawn from the Framingham Heart Study Offspring cohort, a second-generation arm of the landmark U.S. Framingham Heart Study, which launched in 1948.
The ancillary study involved 1,647 middle-aged and older adults who were tracked for about 12 years on average.
Participants completed detailed dietary questionnaires, underwent at least two brain MRI assessments between 1999 and 2019 and were free of dementia and stroke at their first brain MRI.
Researchers used their dietary intake data to calculate MIND diet scores. These ranged from 0 to 15, with a higher score indicating closer adherence.
What is the MIND diet?
The MIND diet, focused on protecting the aging brain, was developed by researchers at Rush University Medical Center in Chicago.
The diet combines elements of the Mediterranean and the DASH (Dietary Approaches to Stop Hypertension) diets. It also targets specific foods and nutrients that past studies linked to brain protection.
The dietary pattern emphasizes nutrient-dense whole plant foods, plentiful in antioxidants and anti-inflammatory phytochemicals, and limits foods associated with vascular risk and accelerated brain aging, such as red and processed meats, as well as foods high in added sugars and saturated fat.
What the new study found
Greater adherence to the MIND diet was consistently linked to slower brain atrophy over the 12-year follow-up period. Specifically, participants had a slower loss of grey matter, the part of the brain involved in thinking, memory, information processing and decision-making.
Each three-point increase in the MIND diet score was associated with 20-per-cent less grey matter shrinkage, equivalent to a 2½-year delay in brain aging over the study period.
Brain imaging also identified slower enlargement of brain ventricles among participants with higher scores, which equated to about one less year of brain aging. Ventricles in the brain are fluid-filled spaces that expand to fill the void left when brain tissue atrophies.
Stronger associations were observed in older participants, suggesting greater benefits among those at higher risk of brain aging.
Protective effects were also more pronounced in people who were more physically active and in those with a healthy body weight, implying combining the MIND diet with other healthy lifestyle strategies provides greater value.
To arrive at these findings, the researchers adjusted for other risk factors including age, sex, education level, daily calorie intake, body mass index, physical activity and smoking status, as well as health factors such as depression, type 2 diabetes, hypertension, high cholesterol and cardiovascular disease.
This was an observational study that identified associations; it did not prove that the MIND diet directly slows brain aging.
Even so, with more than a decade of observations, the findings provide additional support for the potential cognitive benefits of long‑term adherence to this brain-focused diet.
What to eat – and limit – on the MIND diet
The MIND diet has daily and weekly consumption guidelines for nine brain-healthy food groups.
Leafy greens such as spinach, kale and arugula are recommended daily (at least a half-cup cooked or one cup raw), as are other vegetables (at least one half-cup).
Other daily foods are whole grains (at least three half-cup servings) and olive oil (two tablespoons).
Brain‑healthy foods to eat weekly include berries (at least five half-cup servings), nuts (five one‑ounce servings), beans and legumes (at least three half-cup servings), fish (at least one three- to five‑ounce serving) and poultry (at least two three- to five‑ounce servings).
The diet also puts limits on five brain-unhealthy food groups.
These include red and processed meats (no more than three servings a week), butter and stick margarine (no more than one teaspoon a day, or seven teaspoons a week) and full‑fat cheese (no more than one small serving a week, about one ounce).
Pastries and sweets should be limited to no more than four small servings a week and fried or fast foods to no more than one meal a week.
You don’t have to follow the MIND diet perfectly. Even moderate adherence has been associated with cognitive benefits in observational studies.
Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan.
