You are what you eat, is a long held belief, but determining how nutrients affect our bodies has been a difficult. Despite that difficulty, a group of researchers from Oregon Health Sciences University, in Portland, recently published results of a study that tried to determine the relationship between certain vitamins and brain function.
The researchers led by Dr. G.L. Bowman of the Department of Neurology wanted to look at the influence of a panel of 30 biomarkers in the blood on measurable aspects of memory, attention, language, thought processing, global function and depression on a group of 104 healthy adults ranging in age from 65 to 87 years. The study was funded by the National Center for Complementary and Alternative Medicine, and was published in the January issue of the journal Neurology.
None of the participants had blood vessel disease, high blood pressure or diabetes, but all were at risk for dementia and were part of the Oregon Brain Aging Study. The researchers measured blood plasma levels of vitamins B1, B2, B6, folate, B12, C, D, E and 22 other nutrients including omega-3 fatty acids. A total of 42 participants also underwent magnetic resonance imaging (MRI) exams of their brains, and all underwent cognitive function tests. Such tests ask people to perform a variety of thinking tasks that occur primarily in differing parts of the brain.
When they analyzed the results they found that participants who had higher circulating concentrations of vitamins (C, D, E, and specific B vitamins) scored higher on cognitive function tests and had less total brain shrinkage (measured by MRI) than those with lower concentrations. Similarly, those with higher circulating omega-3 fatty acid concentrations had better executive function than those with lower concentrations.
Conversely, participants who had higher levels of trans fatty acids in their blood had worse cognitive function overall than those with lower concentrations. Trans fatty acids are found in foods made with or fried in partially hydrogenated oil.
As intriguing as the findings are, the study is too small to say conclusively that these nutrients have a beneficial affect on brain function. Perhaps more importantly, the study points the way for future studies demonstrating a feasible way to measure the affect of nutrients on brain health.
In an editorial accompanying the study in the same issue, Drs. Christy C. Tangney, and Nikolaos Scarmeas, of Department of Clinical Nutrition (C.C.T.), Rush University Medical Center, Chicago, IL; and Department of Neurology (N.S.), Columbia
University, New York, NY, said the methods used by Bowman’s team should be used in larger studies with a more varied ethnic group of people.
“If the relationships between cognitive scores and MRI measures with nutrient biomarker patterns are confirmed in a larger, more ethnically diverse sample of older adults,” they wrote, “this approach should be exploited to extract nutrient biomarker patterns predictive of cognitive change.”
By Michael O’Leary