The Mediterranean Diet and Alzheimer's Prevention

Many studies have indicated that diet impacts our brain’s ability to remember. Diets such as the Mediterranean diet have been known to have cognitive benefits and are being rigorously tested to see if they can delay dementia-related cognitive decline.

Changes in the brain can occur years before the onset of Alzheimer's symptoms. These early brain changes indicate a possible opportunity to delay the symptoms of dementia. Scientists are finding many ways to do this, including medications, lifestyle changes, and combinations of these interventions. People can reduce their risk of Alzheimer’s through controlling lifestyle choices such as diet, exercise, and cognitive training.

Certain diets may affect the biological mechanisms of Alzheimer's disease, such as oxidative stress and inflammation. Alternatively, diet may act indirectly by influencing other Alzheimer's risk factors such as diabetes, obesity and heart disease. A new branch of research emphasises the relationship between gut microbes and age-related processes that lead to Alzheimer's.

The Evidence

One observational study found that those following a Mediterranean diet had thicker cortisol regions compared to those that were not following a specific diet. This is significant as patients with Alzheimer's exhibit shrinkage in regions of the brain including cortisol regions. Thus, suggesting cognitive benefit.

A follow-up study found that those who followed the Mediterranean diet closely showed higher glucose metabolism and lower levels of beta-amyloid protein compared to those that did not. Alzheimer's patients show low glucose metabolism and higher levels of beta-amyloid protein.

The Digestive System and The Brain

Scientists are exploring how the biochemistry of food intake and digestion interact with the biochemical environment of the brain. They are specifically investigating how the gut microbiome may influence neurodegeneration and the accumulation of toxic proteins, beta-amyloids; and ultimately the progression of Alzheimer’s.

References:

Mosconi L, Walters M, Sterling J, Quinn C, McHugh P, Andrews RE, Matthews DC, Ganzer C, Osorio RS, Isaacson RS, De Leon MJ, Convit A. Lifestyle and vascular risk effects on MRI-based biomarkers of Alzheimer's disease: a cross-sectional study of middle-aged adults from the broader New York City area. BMJ Open. 2018 Mar 23;8(3):e019362. DOI: 10.1136/bmjopen-2017-019362. PMID: 29574441; PMCID: PMC5875649.

Berti V, Walters M, Sterling J, Quinn CG, Logue M, Andrews R, Matthews DC, Osorio RS, Pupi A, Vallabhajosula S, Isaacson RS, de Leon MJ, Mosconi L. Mediterranean diet and 3-year Alzheimer brain biomarker changes in middle-aged adults. Neurology. 2018 May 15;90(20):e1789-e1798. doi: 10.1212/WNL.0000000000005527. Epub 2018 Apr 13. PMID: 29653991; PMCID: PMC5957301.