And Fish Oil May Not Be So Effective for MCI, Either

Many older people on both sides of the Atlantic consume fish oil supplements, the idea being that the omega-3 fatty acids therein protect just about all the problems of aging.  After some controversy, it’s now accepted that the omega-3s have a protective effect against degenerative changes in blood vessels, and apparently disturbances of heart rhythm.  And their effect on blood vessels may reduce the likelihood of stroke or TIAs.  European studies have suggested that fish consumption may benefit mental functioning.  So the results of a UK study, reported in the American Journal of Clinical Nutrition, are of some interest.

This was a randomized, placebo-controlled study involving 867 healthy septuagenarians, who took either 200 mg EPA (eicosapentaenoic acid) plus 500 mg DHA (docosahexaenoic cid) or matching olive-oil placebo capsules, daily for 2 years.  A battery of cognitive tests was administered at baseline and study’s end. 

Eighty-six percent of the participants completed the study.  Withdrawals and deaths were similar in the two groups.  Omega-3 acid blood levels were significantly higher in the subjects taking the ‘active’ capsules.  There were no changes in average cognitive level scores over the 2-year period, and no differences between the two groups in this respect. 

So this result must be set against other, shorter studies that do show a beneficial effect of fish oil supplements on cognitive function.  Research was ever thus.  The Brits have a TV program called “Bang Goes the Theory” that collects such annoying disagreements.  Maybe we should import it . . .