A new study published in Alzheimer’s & Dementia provides evidence that the MIND diet—a hybrid of the Mediterranean and DASH diets—may help slow cognitive decline in older adults, though its effects vary by race. While both Black and White participants showed benefits, White adults needed only moderate adherence to the diet to see improvements, whereas Black adults required stricter adherence.
Alzheimer’s disease and other forms of dementia are growing public health concerns, particularly for underrepresented racial and ethnic groups. Black and Hispanic older adults have higher rates of dementia than their White counterparts, often due to a combination of socioeconomic disparities, healthcare access issues, and vascular risk factors.
While dietary patterns like the Mediterranean, DASH, and MIND diets are known to benefit cognitive health, most existing research has focused on predominantly White populations. This new study aimed to investigate whether the MIND diet’s protective effects against cognitive decline apply across diverse racial groups and whether benefits differ within specific racial and gender subgroups.
“I am a trained nutritionist and a nutritional epidemiologist and was always interested in learning more about the preventive aspects of nutrition for various diseases, specifically neurodegenerative diseases of aging where there are very limited cures,” said study author Puja Agarwal, an assistant professor at the Rush Alzheimer’s Disease Center at Rush University Medical Center.
The MIND diet emphasizes the consumption of 10 brain-healthy food groups, including leafy green vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and a moderate amount of wine, while limiting five unhealthy food groups such as red meats, butter, cheese, sweets, and fried or fast foods. By focusing on foods rich in antioxidants, healthy fats, and nutrients linked to better cognitive function, the diet is designed to reduce the risk of cognitive decline and neurodegenerative diseases like Alzheimer’s.
For their study, the researchers used data from the Chicago Health and Aging Project (CHAP), a long-term study of older adults in Chicago neighborhoods. The study involved 5,259 participants aged 65 and older, 62% of whom were Black. Participants were followed for an average of nearly eight years, undergoing periodic cognitive tests and dietary assessments.
Diet was measured using a modified Harvard Food Frequency Questionnaire, which asked participants about their intake of 144 food items. From this, researchers calculated MIND diet scores on a scale from 0 to 15, with higher scores indicating greater adherence to the diet’s guidelines.
Cognitive function was assessed using a battery of tests that measured memory, attention, and processing speed. The researchers analyzed how changes in MIND diet scores corresponded to changes in cognitive performance over time. They also adjusted their analyses for factors such as age, education, socioeconomic status, physical activity, and vascular health.
The findings confirmed that adherence to the MIND diet was associated with slower cognitive decline in older adults.
“Eating healthy may help your brain age slower,” Agarwal told PsyPost. “We found that the MIND diet may prevent cognitive decline with aging in both non-Hispanic White and Black older adults. We found that adding one MIND diet-recommended component or limiting any unhealthy component resulted in a rate reduction of cognitive decline equivalent to being two years younger in age.”
However, the relationship between diet and cognitive function was not uniform across racial groups. Among White participants, moderate adherence to the diet—scoring around 7 out of 15 on the MIND diet scale—was sufficient to observe cognitive benefits. In contrast, Black participants needed stricter adherence, scoring at least 8.5, to experience similar effects. This difference suggests that the diet’s protective impact may be influenced by broader social, environmental, or biological factors that vary by race.
Interestingly, the diet’s effectiveness for Black participants diminished when researchers adjusted for lifestyle and vascular health factors, such as physical activity, hypertension, and diabetes. In White participants, however, the association between the MIND diet and slower cognitive decline remained strong, even after accounting for these factors. These findings suggest that disparities in health and lifestyle factors could play a significant role in shaping how dietary patterns influence cognitive aging in different populations.
The researchers also uncovered gender-specific trends within racial groups. Among White participants, women benefited more from the MIND diet than men, suggesting potential biological or behavioral differences in how diet impacts cognition. No such gender differences were observed among Black participants, highlighting the need for further investigation into how intersecting factors like race, gender, and lifestyle interact with diet to affect brain health.
“Different risk factors impact brain health, and these risk factors vary in diverse populations who are underrepresented in Alzheimer’s research,” Agarwal explained. “We need more studies in this space, as diet varies by race/ethnicity, geographical location, socioeconomic status, and personal preferences.”
“Additionally, we need to further examine and understand the mechanistic link between diet and cognition in different subgroups with varying degrees of vascular and lifestyle factors or preexisting comorbidities. With recent advancements in science, using novel biomarkers may help us better understand the role of nutrition in brain health and may help design more targeted nutrition interventions for dementia prevention.”
“Our future goal is to further understand culturally appropriate diets as a critical lifestyle modification to reduce dementia risk in populations at higher risk and explore the factors that impact them.”
The study, “Association of MIND diet with cognitive decline among Black and White older adults,” was authored by Puja Agarwal, Lisa L. Barnes, Klodian Dhana, Xiaoran Liu, Yanyu Zhang, Todd Beck, Marilyn C. Cornelis, Christy Tangney, and Kumar B. Rajan.
