Scientists have found that foods rich in omega-3 fatty acids, such as salmon and nuts, may not benefit thinking skills, as some earlier studies have suggested.
Previous research has indicated that omega-3 fatty acids can reduce the risk of mild cognitive impairment.
“There has been a lot of interest in omega-3s as a way to prevent or delay cognitive decline, but unfortunately our study did not find a protective effect in older women. In addition, most randomised trials of omega-3 supplements have not found an effect,” said study author Eric Ammann of the University of Iowa in Iowa City.
“However, we do not recommend that people change their diet based on these results. Researchers continue to study the relationship between omega-3s and the health of the heart, blood vessels, and brain. We know that fish and nuts can be healthy alternatives to red meat and full-fat dairy products, which are high in saturated fats,” Ammann said.
The study involved 2,157 women age 65 to 80 who were enrolled in the Women’s Health Initiative clinical trials of hormone therapy.
The women were given annual tests of thinking and memory skills for an average of six years.
Blood tests were taken to measure the amount of omega-3s in the participants’ blood before the start of the study.
The researchers found no difference between the women with high and low levels of omega-3s in the blood at the time of the first memory tests. There was also no difference between the two groups in how fast their thinking skills declined over time.
The study was published in the journal Neurology.