You are what you eat. The real you is your brain. Ergo, your brain is what you eat.
Over the years, a plan of eating called the Mediterranean diet has been studied – and contrasted with Keto, Paleo, low fat, low carb, and the Standard American Diet (with the appropriate acronym SAD) – with respect to the impact of diet on brain health. Consistently, the Mediterranean diet, studied alone and in meta-analysis, has borne out as the most protective way of eating for the brain.
Now a new study, recently published in Neurology, reinforces that claim and in a strong way.
Meet the Mediterranean
The Mediterranean diet is a way of eating based on the traditional cuisine of countries bordering the Mediterranean Sea. Imagine that you live in France, Spain or Italy. Your meals are largely comprised of fresh vegetables, fruits, whole grains, beans, nut and seeds, and olive oil. Animal protein is mostly from fish, rarely red meat, and dairy intake is low if at all.
What’s to Like about this Study: Older, At-Risk Participants, Extensive Tests
Although the Mediterranean diet has been studied with respect to brain health in other research, there are some factors to this study that I really like. For starters, the average age of the 512 participants was 70 and the majority were identified as higher risk for Alzheimer’s Disease since they were already suffering from mild cognitive impairment, a common precursor to Alzheimer’s. These participants filled out detailed questionnaires in which they indicated which portions of 148 different foods they had eaten in the past months. Those who frequently ate healthy foods typical of the Mediterranean diet, such as fish, vegetables and fruit, and only occasionally consumed foods such as red meat, scored highly on a scale.
Then (and this part I like most of all) the scientists looked at brain volume and atrophy by examining the brain with magnetic resonance imagery (MRI’s). It is well established that brain shrinkage is commonly seen in those affected with profound memory loss from Alzheimer’s Disease. Such shrinkage, as you can imagine, can rapidly progress and exacerbate Alzheimer’s symptoms.
In addition, all subjects underwent various neuropsychological tests in which cognitive abilities such as memory functions were examined. The research team even looked at biomarker levels (measured values) for amyloid beta proteins and tau proteins in the so-called cerebrospinal fluid (CSF) which are considered biomarker precursors to Alzheimer’s.
The Results are In
The conclusions of the researchers pointed to higher benefits of the Mediterranean diet eaters in all respects. Compared to those who ate other (less healthy) diets, the participants on a Mediterranean diet did better on the cognitive memory tests and had fewer pathological biomarkers for Alzheimer’s in their cerebral spinal fluid.
And their brains were bigger! There was a positive correlation between a closer adherence to a Mediterranean diet and higher volume of the hippocampus, the part of the brain responsible for short term memory and new learning. People with Alzheimer’s tend to lose volume early and severely in the hippocampus.
Conclusions and a Note-Taking Challenge
Can one conclude that following a Mediterranean diet protects the brain from atrophy, memory loss and risk of dementia in later years? Not entirely. Remember, optimal brain health is a compendium of lifestyle practices which include exercise, mental activity, socialization and stress management. Of course, other risk factors may also cloud cognition during the soup of life experience - like head trauma, infections, genetics.
But the role of diet in cognitive health cannot be ignored.
Last week, I made a food journal for a dear friend who suffers with various gastric problems, encouraging her to record food intake to rule out whatever might be causing symptoms. Reading this study made me think of a similar recording practice of daily diet to see how the rest of us are faring in diet. To this end, I’m working on developing my own Mediterranean rating scale to help people determine how smart their current diets stack up. When it’s done, I’ll post on my website.
Food for thought?
The study referenced in this article is here:
Mediterranean Diet, Alzheimer Disease Biomarkers and Brain Atrophy in Old Age. Neurology, 2021 DOI: 10.1212/WNL.0000000000012067