NEW YORK (Reuters Life!) - Fish oil may be good for your heart but it doesn’t seem to help keep you smart, according to a two-year British study.
Numerous studies have shown that people who eat more fish have better mental function, and are less likely to develop dementia.
But after studying 748 men and women aged in their 70s, researchers from the London School of Hygiene and Tropical Medicine cast some doubt on this link.
“This is an important finding because a lot of people are taking fish oil in the hopes that it will be good for their cognitive function,” researcher Dr. Alan D. Dangour told Reuters Health.
“The problem with a lot of these studies of course is there are lots of reasons why people eat more fish,” Dangour pointed out but added that he didn’t rule out the possibility that taking fish oil for a longer period of time might have beneficial effects.
The study, published in the American Journal of Clinical Nutrition, involved 748 men and women in their 70s, none of whom had any dementia or other impairment of mental function.
The participants took 200 milligrams of eicosapentaenoic acid (EPA) plus 300 mg docosahexaenoic acid (DHA) every day for two years or a placebo capsule containing olive oil.
EPA and DHA are the two main omega-3 fatty acids found in fish oil.
Neither group showed any change in cognitive function over the 24-month trial, as measured by a battery of tests of mental function they took at the beginning and end of the study.
The percentage of people who died or dropped out was similar in both groups.
“We can clearly say that after two years there’s no evidence for a benefit” in terms of cognitive function, Dangour said.
He and his colleagues noted in their report that their study is the largest and longest randomized controlled trial to date investigating omega-3s and mental function in older people.
This doesn’t mean that people might benefit their brains by taking fish oil capsules for longer than two years, he added. But, he said: “There’s no good evidence at the moment from randomized controlled trials that it’s good for cognitive function.”
Reporting by Anne Harding of Reuters Health, Editing by Belinda Goldsmith