The evidence for eating fish got a boost last week.
The headline: Eating fish at least once a week decreases the risk for Alzheimer’s pathology. What was unique about this study is that instead of giving subjects tests of mental ability, their brains were autopsied for numerous pathologies associated with Alzheimer’s, including plaques and tangles. Also measured was the amount of mercury and selenium in the brain tissue. Mercury is a neurotoxin whose toxicity is reduced by selenium. A question was if the mercury in the fish would negate the benefits of the fatty acids. During the course of this nine-year study, subjects had regularly provided dietary records for analysis.
There was more mercury in the brains of subjects who ate more seafood, but it did not have an effect on neurological damage. In fact, people who reported a higher seafood intake were less like to have the amyloid plaques common in Alzheimer’s disease. They also had higher selenium levels, which can be protective against mercury. These findings were most significant in individuals who have a strong genetic risk for Alzheimer’s disease. This study supports similar findings from animal studies. The authors state that there might have been a smaller correlation for the benefits of fish for people not at high risk for Alzheimer’s, but this study did not have the statistical power to show that.
As we age, the amount of the fatty acid DHA decreases in the brain. Fatty fish is a great way to counteract this process. And as with most foods, fish is not a monotasker. Eating fatty fish such as salmon, sardines and tuna lowers the risk of dying from heart disease, reduces inflammation in the body and might even ease mild depression. And fish is a great source of protein. I’ve tried a few of these recipes from Cooking Light (http://www.cookinglight.com/food/top-rated-recipes/best-seafood-recipes and they were all quite tasty.
Sheah Rarback is a registered dietitian on the faculty of the University of Miami Leonard M. Miller School of Medicine. Follow her on Twitter @sheahrarback.