Do Omega-3 Fatty Acids Really Bolster Aging Brains?
“Eat your fish — it’s brain food,” our mothers told us, and we repeat that mantra to our own children. For years we’ve heard that fish, especially fatty fish such as salmon, is good for our brain health. And many scientists identified omega-3 fatty acids as the substance in the fish that would help our math skills, keep us alert and preserve our brain health. That made sense because omega-3 fatty acids — which are also found in high levels in tuna, sardines and trout — are a type of fat that is crucial in brain function.
Based on those ideas, plenty of people started taking fish oil pills with omega-3s to keep their brains sharp — after all, the pills don’t stink up the kitchen. But some scientists weren’t sure all those logical leaps — from fish to pills to brain health — really made sense. In 2012 a group of scientists reviewed all the scientific literature on omega-3s supplements. Their analysis found that the pills didn’t seem to help brain health. A new study published in the journal Neurology supports that finding, at least when it comes to older women.
The new study involved 2,157 women ages 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-3 fatty acids in the participants’ blood before the start of the study. Researchers at the University of Iowa analyzed these tests and found no difference in memory tests between the women with high and low levels of omega-3s in the blood. They also didn’t find that omega-3s made any difference in how fast thinking skills declined. A couple of important caveats: The researchers did not measure the women’s dietary intake of omega-3 fats, only blood levels at the beginning of the study. Those levels may have changed over time.
Where did omega-3 fats get their brain-healthy reputation? The Neurology study’s lead author, Eric Ammann, an epidemiologist with the University of Iowa, said that although previous studies have found that omega-3s seem to protect brain function, those studies didn’t prove cause and effect. There could be other factors influencing the results. “People who eat lots of fish or nuts, or who take omega-3 supplements, tend to be more affluent and health conscious than those who don’t. They are also less likely to smoke, more likely to exercise, and have a lower body mass index,” he said.
Ammann says the take-home advice from his study comes down to this: Keep the fish in your diet, but consider talking to your doctor about the supplements.