There have been many studies showing the correlation between a healthy brain and high levels of omega-3 fatty acids. Your grandma probably told you, “eat your fish, it is good for your brain.”

A new study published in the December 28 issue of Neurology is unique, however, because researchers measure nutrient biomarkers in the blood….testing for omega-3 and other vitamin levels including B, C, D and E.

Previous studies have used data from diet questionnaires.

The paper’s first author is Dr Gene Bowman from the Departments of Neurology and Public Health and Preventive Medicine at Oregon Health & Science University in Portland, and a member of the American Academy of Neurology. He and his colleagues describe three sets of findings:

  1. Elderly people with diets high in several vitamins or omega 3 fatty acids were less likely to have the brain shrinkage that usually accompanies Alzheimer’s disease than people whose diets were low in those nutrients.
  2. Those whose diets were high in omega 3 fatty acids and in vitamins C, D, E and the B vitamins were also more likely to score better on tests of mental ability than those whose diets were low in those nutrients.
  3. Those whose diets were high in trans fats were more likely to have brain shrinkage and perform less well on thinking and memory tests than those whose diets were low in trans fats.

For the study, Bowman and colleagues recruited 104 elderly people of average age 87 who had few risk factors for impaired memory and thinking. From participants’ blood tests the researchers measured 30 different nutrient biomarkers. All the participants also completed tests of memory and thinking, while 42 of them also underwent MRI scans that measured their brain volume.

The results showed that overall the participants’ diets were healthy, but 25% were lacking in vitamin D and 7% were deficient in vitamin B12.

Bowman told the press that their results showed a significant amount of the variation in brain volume and scores on the thinking and memory tests were tied to levels of nutrients biomarkers.

On the thinking and memory tests, the nutrient levels accounted for 17% of the variation in the scores, while 46% of the variation was tied to other factors such as age, number of years of education and blood pressure.

For brain volume, the nutrient levels accounted for 37% of the variation.