Mediterranean diet linked to better brain health in Hispanic/Latino adults

Closely following a Mediterranean diet was associated with having better brain health among Hispanic/Latino adults in a preliminary study to be presented at the American Stroke Association's International Stroke Conference 2025. The meeting is in Los Angeles, Feb. 5-7, 2025, and is a world premier meeting for researchers and clinicians dedicated to the science of stroke and brain health.

A Mediterranean-style diet typically includes eating plenty of fruits, vegetables, whole grains; beans, nuts and seeds; with olive oil as a primary fat source; and low-to-moderate amounts of dairy products, eggs, fish and poultry.

Researchers noted that the positive impact of the Mediterranean diet on brain health is not entirely influenced by cardiovascular risk factors such as blood pressure, cholesterol levels and blood sugar, nor by behavioral risk factors such as smoking and physical activity, all known to affect brain health.

We have observed that cardiovascular health directly impacts brain structures; the effect of the Mediterranean diet on communication between regions of the brain remains somewhat independent of cardiovascular health. Even when considering age and cardiovascular health in people who ate a Mediterranean diet, the brain demonstrated improved organization of the fibers connecting different brain regions and enhanced communication, known as white matter integrity."

Gabriela Trifan, M.D., lead researcher, assistant professor of neurology, University of Illinois, Chicago

"Other studies have shown that adherence to the Mediterranean diet is associated with less brain shrinkage – called atrophy. This is the first large study focused solely on Hispanics/Latinos – who are projected to be the fastest-growing ethnic group in the U.S.," she said.

Researchers tapped into a multisite, population-based longitudinal study of Hispanic/Latino adults aged 18 to 74 years to explore how to preserve their brain integrity.

Researchers used specialized imaging techniques to investigate the microscopic and the visible changes in the brain. Adherence to Mediterranean diet intake was measured at baseline, and each participant received a score between 0-9, with higher scores indicating higher adherence. The average Mediterranean diet score was 5.01.

After considering other factors that could affect brain health, the analysis found that for each point increase in the Mediterranean diet score:

• there was an improvement in white matter integrity (organization and communication within the brain); and

• there was less evidence of structural damage in the brain, as assessed by the white matter hyperintensity burden (an important marker of small vessel brain disease).

"This suggests that even small improvements in diet improved brain integrity," Trifan said. "It has been suggested that healthy diets, and particularly the Mediterranean diet, improve white matter integrity by reducing inflammation, reducing oxidative stress and through maintaining the health of the brain's blood vessels' function and stable blood sugar levels, all important factors for optimal brain health."

"These results matter because many health care professionals may not know about the eating habits of Hispanic/Latino adults, who consume many foods from the Mediterranean diet. The findings support the American Heart Association's advice to follow this diet as one of the dietary plans that may help prevent strokes and potentially avoid cognitive issues. The study suggests that the Mediterranean diet can benefit brain health and integrity, specifically concerning white matter. White matter is a crucial part of the brain that connects different areas and networks, helping us to function effectively. However, we still need to learn more about brain health and the Mediterranean diet, as the positive effects were only partly related to vascular risk factors," said Philip B. Gorelick, M.D., M.P.H., FAHA, immediate past chair of the American Heart Association's Stroke Brain Health Science Subcommittee and professor of neurology in the Ken & Ruth Davee Department of Neurology at Northwestern University's Feinberg School of Medicine in Chicago. Gorelick was not involved in the study.

Study background and details:

• Study of Latinos-Investigation of Neurocognitive Aging-MRI Ancillary study included approximately 2,800 participants aged 18 to 74 years old, 45% men, 55% women.
• Participants completed 24-hour dietary recalls of predefined food and nutritional categories at baseline (2008-2011). A second dietary recall was conducted roughly 30 days later. Dietary intake was determined for participants with two dietary recalls by calculating the average of both recall questionnaires to calculate the Mediterranean diet score (range 0-9). The Mediterranean diet was confirmed only at the baseline visit.
• The magnetic resonance imaging (MRI) acquisition began in 2017 and ended in 2022.
• Researchers used specialized brain MRI techniques and sequencing called diffusion tensor imaging and fluid-attenuated inversion recovery (FLAIR) to investigate microscopic and visible changes in the brain.
• Cardiovascular health was assessed using the American Heart Association Life's Simple 7 score components - exercising regularly, eating a healthy diet, not smoking, avoiding excess weight, and keeping blood pressure, cholesterol and blood sugar levels within a healthy range. Note: In June 2022, the Association updated Life's Simple 7 to Life's Essential 8, adding sleep.

Among the study's strengths are its focus on the largest, diverse group of middle-aged and older Hispanics/Latinos living in the U.S.

The study's limitations include that many variables were self-reported with possible recall bias. Also, as MRI measurements were collected between 2017 and 2022, individuals may have adopted new dietary and lifestyle habits that may have altered the association documented at baseline.

"Many Mediterranean diet components are already staple Latin foods (beans, corn, tomatoes, peppers, avocado and fish). Our study will help guide Hispanic/Latino individuals toward consuming more of the beneficial dietary components of the Mediterranean diet without significantly altering their already established diet," Trifan said.