New Study Suggests Mediterranean Diet May Slow Cognitive Decline
Is there anything this diet can’t do?
The Mediterranean diet may get a lot of hype, but evidence keeps coming in to back up its myriad health benefits. Most recently, a nutritional cognitive neuroscience study published in the journal Nature Aging demonstrates that this lifestyle may help slow down the brain for the better. By looking for specific biomarkers, its authors identified certain nutrients linked to slower cognitive decline. And, it just so happens that the Mediterranean diet is replete with these nutrients.
The authors from the University of Illinois, Urbana and the University of Nebraska-Lincoln describe their study as “one of the largest and most comprehensive” nutrient biomarker investigations looking at various measures of brain health. The team of psychologists and neuroscientists looked at 139 biomarkers from 100 healthy adults between 65 and 75 indicative of brain health and function. They collected blood samples and conducted brain scans by magnetic resonance imaging (MRI), and participants also completed tests of intelligence, executive function, and memory.
Brains with delayed aging showed four characteristics: larger volumes, better structural integrity, better functional connectivity, and larger concentrations of certain metabolites. Participants whose brains showed delayed aging also scored higher on their cognitive assessments compared to those with accelerated aging.
Tomatoes are full of carotenoids while olive oil is full of fatty acids.
A clear nutrient profile associated with delayed aging emerged. The fatty acids α-linolenic acid (ALA) and eicosapentaenoic acid (EPA) — found in fish, shellfish, flaxseed, hemp seed, olive oil, soya oil, canola oil, pumpkin seeds, sunflower seeds, walnuts, and leafy vegetables — were part of their diet, known to reduce inflammation. So were long chain fatty acid lignoceric acid, found in peanuts and macadamia nuts, which have been associated with reduced cognitive decline, something supported in a 2020 paper in The American Journal of Clinical Nutrition.
Also abound in the delayed aging diets were carotenoids, which give fruits and vegetables their vivid colors, possess antioxidants and are associated with improved brain structure, network function, and memory. Spinach, kale, corn, bell peppers, tomatoes, watermelon, grapefruit, cantaloupe, broccoli, and carrots are all chock full of these pigments.
Regarding vitamins, high concentrations of vitamin E in the blood were found to be associated with improved cognition. Nuts, seeds, vegetable oils, leafy green vegetables, and fortified grains are significant vitamin E sources. And choline, which is an essential B-vitamin-like nutrient, keeps brain volume and cellular structure healthy, benefitting both executive function and memory, as a 2021 randomized trial in The Journal of Nutrition demonstrates. Animal proteins like meat, poultry, fish, and eggs, as well as cruciferous vegetables like broccoli and cabbage, all deliver significant choline.
Of course, this all leads up to a diet that is healthy by any measure. Whether it’s directly associated with brain health, well, the authors acknowledge the study needs follow-up. While preliminary research on long chain fatty acids suggest their benefits, they require more investigation to cement the correlation. Furthermore, this study must also be conducted with non-white participants in order to test its generality.
Limitations of this study aside, you could do worse than to tuck in to a Mediterranean diet on the daily. By most indications it’s far superior for health and longevity than the processed Western diet. Also, it’s nearly tomato season. And what’s better than a fresh, juicy, caratenoid-rich tomato sandwich (full of lettuce, whole wheat bread, and drizzled with olive oil, naturally.)
