For many years now, the Mediterranean diet has been promoted as an eating style associated with better physical and mental health. In light of that information, researchers at the University of Illinois Urbana-Champaign took a close look at 32 important nutritional substances associated with a Mediterranean diet to see which could be specifically linked to healthier cognitive performance in older adults. Their findings, published online in December 2018 and in the March 2019 issue of the journal NeuroImage, narrowed the benefits down to eight key nutrients.
Rather than rely on standard food questionnaires that require study participants to recall what and how much they ate during specific periods of time, or traditional cognitive testing, the researchers used blood analysis to examine the participants' actual nutrient status and MRIs (magnetic resonance images) to measure the efficiency of their brain networks. These direct methods of collecting information gave the researchers clearer and more accurate evidence of any associations between diet and brain health.
The researchers narrowed down the 32 nutritional substances provided by a traditional Mediterranean diet to several that appear to play key roles in healthy brain aging, enhanced cognitive performance, functional brain network efficiency, executive function, and general intelligence. These include omega-3 fatty acids, found in significant amounts in fatty fish and fish oils; omega-6 fatty acids, found in vegetable oils, nuts, seeds, poultry products, and whole grains; lycopene, found in red-pigmented plant foods, such as tomatoes and watermelon; carotenoids found in yellow- and orange-pigmented foods, such as sweet potatoes, winter squash, and carrots; vitamin D, found mostly in fatty fish and fortified dairy products and dairy substitutes, such as soy milk; and the B vitamins riboflavin, found in dairy products and enriched grains; folate found in dark leafy greens and other vegetables and fruit; and B12, found in animal products such as meat, poultry, fish, eggs, dairy, and fortified breakfast cereals. A subset of the original study participants returned two years later for a follow-up, and similar nutrient patterns were confirmed.
However, it’s not just the consumption of these individual nutrients that impacts brain health and cognitive efficiency, the researchers found, but rather the way they work together and are processed collectively by the body that’s most important. That’s why nutrition experts recommend, whenever possible, to get your nutrients from a varied, balanced diet, where they are naturally packaged together in healthful and useful amounts, rather than from individual dietary supplements taken in random doses.
Ongoing research continues to focus on the benefits of eating a Mediterranean-style diet, because this particular eating pattern ensures the availability of a great variety of nutrients known to be essential for disease prevention and long-lasting health. (Of course, in cases where specific nutrients are not readily available in the diet, a doctor or nutritionist may recommend supplements.) If you’re still not familiar with a traditional Mediterranean style of eating, the best place to start learning about it is from the Oldways organization, which was responsible for the original Mediterranean Diet Pyramid and has since developed variations on the original, adapted to the types of foods featured in other cuisines.
Nutrient Biomarker Patterns, Cognitive Function, and fMRI Measures of Network Efficiency in the Aging Brain. NeuroImage. March 2019; 188: 239-251.