Omega-3 fatty acids are praised for keeping bodies healthy from the heart to the brain. But new research is questioning how strong the relationship is between omega-3 consumption and health.
A new study conducted by University of Iowa researchers published Wednesday in the journal Neurology questions the influence of omega-3s on cognitive development.
Earlier this summer, a study published in Journal of the National Cancer Institute caused a stir when it linked omega-3 fatty acids to an elevated risk of prostate cancer. Although many experts called the link “fishy,” it did raise the argument that these fatty acids are more complex than we previously thought.
The Iowa researchers looked at 2,157 women between the ages 65 and 80 and measured the amount of natural omega-3s in their blood. After the measurements, the women were given tests to assess their thinking and memory skills. The tests were repeated over six years.
At the end of the study, there were no notable differences among the cognitive abilities of the women with higher levels of omega-3s versus the women with lower levels. Another earlier review by the Cochrane Library also reported that the cognitive benefits of omega-3s may be overstated: healthy older adults taking omega-3 supplements did no better on thinking and verbal assessments than participants taking placebo.
The new study is additional support for the view that omega-3s may not have all benefits once believed. “Currently there is no proof, no indication, no convincing reason to take omega-3s for treatment or prevention of cognitive problems,” says Dr. Nikos Scarmeas, an associate professor of neurology at Columbia University. Scarmeas is unaffiliated with the study.
Beyond brain health, other research has questioned whether taking omega-3 fatty acid supplements really protects against eye disease like macular degeneration, as eye doctors have sometimes recommended. Even some of the cardiovascular benefits have raised skepticism among heart health professionals.
“At one point, omega-3s were looked to as a very hopeful supplement for people at high risk for heart disease,” says Dr. David A. Friedman, chief of the Heart Failure Services at North Shore-LIJ’s Franklin Hospital in Valley Stream, New York. “But it hasn’t shown the risk reduction we want to see. There may been reports of decreases to things like blood clots, but I’m not sure all the data supports this.”
How omega-3s are consumed may also be important to keep in mind. For instance, getting omega-3s naturally from fish may be better than getting them through supplement form. ”
Dr. Friedman says that consuming omega-3s became popular in part after researchers learned that hunter-gatherer societies with diets rich in omega-3s had greater overall health.
“There was a hope that this could be translated over, but simply pulling out the supplement isn’t enough,” says Dr. Friedman. “It’s a controversial topic, the data is becoming less ideal.”