Seattle, WA—New research published in JAMA Neurology gives us yet another reason to limit saturated fats in the diet.

A research team lead by Angela J. Hanson, M.D., of the Veterans Affairs Puget Sound Health Care System and the University of Washington, Seattle, and colleagues pulled together a group of 20 older adults with normal cognition and 27 older adults with mild cognitive impairment. Everyone was assigned to eat either a high-glycemic, high-saturated fat diet (45% energy from fat, more than 25% saturated fat) or a low-glycemic, low-saturated fat diet (25% of energy from fat, less than 7% saturated fat). Both diets had the same amount of calories.

At baseline and after a month, blood samples and cerebrospinal fluid (CSF) samples (via lumbar puncture) were taken and analyzed. Researchers found that those with mild cognitive impairment tended to have higher levels of lipid-depleted beta-amyloid peptides in their system at baseline. Beta-amyloid plaque accumulation is a characteristic of those with Alzheimer’s disease. End-study results indicate that the low-saturated fat diet was linked to lower levels of lipid-depleted beta-amyloid peptides; the reverse was true of the high-saturated fat group.

The researchers believe that saturated fat reduced levels of apolipoprotein E (ApoE) in the body. ApoE helps remove beta-amyloid proteins from the brain.

Published in WholeFoods Magazine, August 2013 (online 6/26/13)