Researchers compared seven healthy eating patterns to explore their potential effects on brain health.
The Mediterranean and DASH diets were associated with better performance in certain areas of cognition.
Long-term benefits were less clear, suggesting that diet may be just one part of protecting brain health as we age.
Eating well is often associated with benefits for heart health, weight management, and overall wellness. But could certain eating patterns also help keep the brain healthy as we get older?
Researchers are taking a closer look at that question, particularly as dementia and cognitive decline become growing public health concerns. Although previous research has explored connections between food and brain health, differences in how studies measure diets and cognitive performance have made it difficult to draw consistent conclusions.
A new study published in The Journal of Nutrition takes another look at the relationship, comparing seven established dietary patterns to see which ones may be associated with stronger thinking skills and cognitive performance.
How the researchers compared different diets
For the study, researchers analyzed data from 17,368 participants across multiple studies conducted in the United States and Europe.
Rather than asking everyone to follow a particular diet, the team used existing information about participants' eating habits. That information came from food questionnaires, dietary histories, and food records. Researchers then standardized the information to measure how closely participants followed seven different eating patterns.
Those patterns included the Mediterranean diet, the DASH diet (Dietary Approaches to Stop Hypertension), and the MIND diet, which combines elements of Mediterranean and DASH eating recommendations. The researchers also examined the Healthy Eating Index-2020, Alternate Healthy Eating Index-2010, EAT-Lancet diet, and a continuous version of the Mediterranean diet.
The team looked at both overall cognitive performance and executive function, which refers to mental skills that help people plan, make decisions, solve problems, and manage everyday tasks.
What the findings could mean for consumers
The results showed some encouraging connections. Participants who more closely followed the continuous Mediterranean diet tended to perform better on measures of overall cognition. Greater adherence to both the DASH diet and continuous Mediterranean diet was also associated with better executive function.
However, the findings were not as consistent when researchers looked at changes over time. Although several eating patterns were associated with better cognitive performance in one-time comparisons, those connections did not consistently translate into better long-term outcomes. Only the MIND diet was associated with more favorable executive function over time, based on data from three U.S. study groups.
For consumers, the findings offer another reason to pay attention to dietary quality, but they don't establish that following a particular diet will prevent dementia or stop cognitive decline.
The researchers suggest that healthy eating may be most helpful when combined with other lifestyle habits, including regular physical activity.
In other words, there's no single dietary change that guarantees better brain health, but maintaining a balanced diet may be one useful part of a broader approach to healthy aging.