Nutrition in early adulthood plays role in middle age brain function
A heart-healthy diet rich in fruits and vegetables, moderate in nuts, fish, and alcohol, and low in meat and full-fat dairy is associated with better middle age cognitive function, including thinking and memory skills, according to a new study published in the journal Neurology.
The study, led by Claire McEvoy, PhD, of Queen's University Belfast in Northern Ireland, investigated where dietary patterns, including the Mediterranean diet, Dietary Approaches to Stop Hypertension (DASH), and A Priori Diet Quality Score (APDQS), during early adulthood were associated with midlife cognitive performance.
Researchers looked at 2,621 Coronary Artery Risk Development in Young Adults (CARDIA) study participants with an average age of 25 years old over a 30-year period. Participants were asked about their diet at the beginning of the study, after seven years, and after 20 more years. The participants’ cognitive function was tested twice, when they were about 50 and 55 years old.
For each diet, study participants were divided into one of three groups, low, medium, or high adherence, based on how closely they followed the diet. The study found that the DASH diet was not associated with any change in cognitive performance. However, adherence to a Mediterranean diet or APDQS diet resulted in less decline in cognitive function.
People with high adherence to the Mediterranean diet were 46 percent less likely to have poor thinking skills than people with low adherence to the diet, according to the study. Of the 868 people in the high adherence group, 9 percent had poor thinking skills, compared to 29 percent of the 798 people in the low adherence group.
People with high adherence to the APDQS diet were 52 percent less likely to have poor thinking skills than people with low adherence to the diet. Of the 938 people in the high adherence group, 6 percent had poor thinking skills, compared to 32 percent of the 805 people in the low adherence group, researchers found.
The results were adjusted for other factors that could affect cognitive function, such as the level of education, smoking, diabetes, and physical activity, according to the study.
While the diet protocols are somewhat similar, the Mediterranean diet emphasizes whole grains, fruits, vegetables, healthy unsaturated fats, nuts, legumes, and fish, and limits red meat, poultry, and full-fat dairy. In comparison, the DASH diet emphasizes grains, vegetables, fruits, low-fat dairy, legumes, and nuts, and limits meat, fish, poultry, total fat, saturated fat, sweets, and sodium. Lastly, the APDQS diet emphasizes fruits, vegetables, legumes, low-fat dairy, fish, and moderate alcohol, and limits fried foods, salty snacks, sweets, high-fat dairy, and sugar-sweetened soft drinks.
Both the Mediterranean diet and the DASH diet consistently rank in the best diets for humans, according to the U.S. News and World Report’s annual rating. It is unclear why the DASH diet did not result in better cognitive function, researchers said.
Additional studies are needed to define the combination of foods and nutrients for optimal brain health across the life course, according to McEvoy in a statement released by the American Academy of Neurology.
“While we don’t yet know the ideal dietary pattern for brain health,” she said, “changing to a heart-healthy diet could be a relatively easy and effective way to reduce the risk for developing problems with thinking and memory as we age.”