Fish for brain health supported by trio of studies

Omega-3-rich fish consumption may improve brain function across a broad demographic spectrum, suggest three new studies from around the world.

The studies pull together data from New Zealand, the Netherlands, and Norway, and all suggest significant benefits of fish consumption, specifically the omega-3 fatty acid content, and cognitive health.

Published in the November 2007 issue of The American Journal of Clinical Nutrition, the studies have been commended by an independent expert.

"These recent reports are novel in that they address the association of n-3 fatty acid intake and cognitive function in non-demented individuals and, thus, present a shift in the attention to earlier stages of cognitive decline with the hope of preventing progression to states of dementia and disability before they become irreversible," wrote Irwin Rosenberg from Tufts University.

For the first study, Dutch researchers reported that increased levels of omega-3 fatty acids in the plasma were associated with a 69 per cent lower decline in sensorimotor speed and a 60 per cent lower decline in complex speed over three years in 807 participants.

Researchers in New Zealand investigated if a relationship existed between the fatty acid composition of serum lipids and the mental and physical well-being of 2416 people participating in the 1997 National Nutrition Survey. The ratio of EPA to arachidonic acid (AA) was positively associated with physical well-being, and the EPA to AA ratio for mental well-being. "The synthesis of the inflammatory series-2 prostaglandins and series-4 leukotrienes from AA would be reduced in favour of the less inflammatory series-3 prostaglandins and series-5 leukotrienes synthesized from EPA."

The final study, led by Eha Nurk from the University of Oxford, examined the relation between consumption of seafood products and cognitive performance in 2031 elderly Norwegians. The researchers report that consumption of at least 10 grams of fish a day performed significantly better in tests for cognitive performance than people who ate less than 10 grams of fish and fish products. Moreover, the effect was dose dependent, with the best test scores occurring in individuals consuming about 75 grams per day.

In the accompanying editorial, Rosenberg commended the research groups for addressing the association of fish and n-3 fatty acid intake with cognitive function in individuals not yet showing signs of impaired cognitive function.

"These studies of nutritional associations with brain function during the elongated prodromal period of age-related neurodegeneration and decline offer an opportunity for early intervention to maintain brain function and slow progression to dementia, which is costly economically and in terms of quality of life," concluded Rosenberg.

Bonnie - a-ha! Another study shunning the disease model and focusing on prevention? I love it!