A study, led by Dr. Nikolaos Scarmeas from Columbia University Medical Center, New York suggests that eating a Mediterranean-style diet high in vegetables, fruits and nuts, legumes, fish and cereals, and low in dairy products, meat, and fat, with moderate alcohol consumption, is not only good for the heart, it’s also good for the brain.
Scarmeas found that following Mediterranean diet-type habits was associated with reduced risk for getting mild cognitive impairment -- a transitional stage between normal cognition and dementia/Alzheimer’s disease. Additionally, subjects who already had mild cognitive impairment and had a higher adherence to the Mediterranean diet had lower risk for converting to Alzheimer’s disease.”
Scarmeas and colleagues, used food frequency questionnaires to calculate Mediterranean diet “adherence scores” for 1,393 individuals with no cognitive difficulties at the outset and 482 individuals with mild cognitive impairment at the start of the study. 275 of the subjects who had normal brain function at the outset developed mild cognitive impairment over an average of 4.5 years of follow-up.
Those who followed the diet had a 28% lower risk of developing mild cognitive impairment than those who didn’t. Furthermore, the subjects with intermediate Mediterranean diet adherence scores had a 17% lower risk, the researchers found.
Among the group of people with mild cognitive impairment at the beginning of the study, 106 progressed to Alzheimer’s disease during follow-up and good adherence to the Mediterranean diet was associated with a lower risk for this transition. Specifically, the of subjects with the highest scores for Mediterranean diet adherence had 48% less risk and those with intermediate Mediterranean diet adherence had 45% less risk than the subjects with the lowest scores.
“This is not a clinical trial, it is only an observational study,” Scarmeas pointed out. “We cannot, therefore, say that the Mediterranean diet is definitely useful for neurological conditions such as mild cognitive impairment. Having said that, since we already know that Mediterranean diet is helpful for other conditions (coronary heart disease, diabetes, hypertension, etc.), it makes sense.”
The Mediterranean diet, the researchers explain, may improve cholesterol levels, blood sugar levels and blood vessel health, or reduce inflammation, all of which have been associated with mild cognitive impairment. Individual food components of the diet also may impact brain function. “For example, potentially beneficial effects for mild cognitive impairment or mild cognitive impairment conversion to Alzheimer’s disease have been reported for alcohol, fish, polyunsaturated fatty acids (also for age-related cognitive decline) and lower levels of saturated fatty acids.”
Source: Archives of Neurology, February 2009.