Mediterranean-style diet cuts risk of Alzheimer’s disease by 68 percent

New research indicates that the Mediterranean diet rich in antioxidants and polyphenols reduce oxidative stress and protect against the development of Alzheimer’s disease.

The Mediterranean diet, rich in cereals, wine, fruits, nuts, legumes and whole grains, fish and olive oil, has been linked to lower incidence of heart disease, protection against some cancers, and a longer life. The diet’s main nutritional components include beta-carotene, vitamin C, tocopherols, polyphenols and essential minerals. A new study published on-line in the Archives of Neurology indicates that it is these antioxidants and polyphenols that appear to offer protection, not simply an improvement in heart health.

After adjusting the results for age, education, BMI, smoking status, and ethnicity, the researchers reported that people with the highest adherence to a model Mediterranean diet were associated with a 60 per cent lower risk of Alzheimer’s disease, compared to people with the lowest adherence to the diet.

When the researchers took into account general heart health, such as history of stroke, hypertension, heart disease, diabetes, and cholesterol, the associations for the high adherence group grew stronger, with an associated risk reduction of 68 per cent.

These results indicate that the protection gained by following a Mediterranean- type diet is not a result of the cardiovascular factors, and it may be more related to factors such as inflammation and oxidative stress. The researchers noted that the Mediterranean diet contains high levels of important antioxidants and polyphenols, and it could be the combination of these various dietary compounds that could partially explain the reduced risk of Alzheimer’s Disease.

The study follows another study by the same researchers, published earlier this year in the Annals of Neurology (Vol. 59, pp. 912 – 921), in which elderly individuals whose diet closely resembled the Mediterranean diet had a 40 per cent lower risk of Alzheimer’s than those who followed the diet the least.