U. PITTSBURGH (US) — Healthy young adults who are at the “top of their cognitive game” can improve their working memory by increasing omega-3 fatty acid intake, research shows.
While omega 3s—found in foods like wild fish and grass-fed livestock—are necessary for human body functioning, their effects on working memory have not been studied until now.
The findings are published in the journal PLoS One.
“Before seeing this data, I would have said it was impossible to move young healthy individuals above their cognitive best,” says Bita Moghaddam, project investigator and professor of neuroscience at the University of Pittsburgh. “We found that members of this population can enhance their working memory performance even further, despite their already being at the top of their cognitive game.”
Led by Rajesh Narendarn, project principal investigator and associate professor of radiology, researchers sought healthy young men and women between the ages of 18 and 25 from all ethnicities to boost their omega-3 intake with supplements for six months. They were monitored monthly through phone calls and outpatient procedures.
Before they began taking the supplements, all participants underwent positron emission tomography (PET) imaging, and their blood samples were analyzed. They were then asked to perform a working memory test in which they were shown a series of letters and numbers. The young adults had to keep track of what appeared one, two, and three times prior, known as a simple “n-back test”.
“What was particularly interesting about the pre-supplementation n-back test was that it correlated positively with plasma omega-3,” Moghaddam says. “This means that the omega-3s they were getting from their diet already positively correlated with their working memory.”
After six months of taking Lovaza—an omega-3 supplement approved by the Federal Drug Administration—the participants were asked to complete the series of outpatient procedures again. It was during this last stage, during the working memory test and blood sampling, that the improved working memory of was revealed.
“So many of the previous studies have been done with the elderly or people with medical conditions, leaving this unique population of young adults unaddressed,” says Matthew Muldoon, project co-investigator and associate professor of medicine.
“But what about our highest-functioning periods? Can we help the brain achieve its full potential by adapting our healthy behaviors in our young adult life? We found that we absolutely can.”
Although the effects of omega-3s on young people were a focus, the team was also hoping to determine the brain mechanism associated with omega-3 regulation.
Previous rodent studies suggested that removing omega-3 from the diet might reduce dopamine storage (the neurotransmitter associated with mood as well as working memory) and decrease density in the striatal vesicular monoamine transporter type 2 (commonly referred to as VMAT2, a protein associated with decision making).
Therefore, the researchers posited that increasing VMAT2 protein was the mechanism of action that boosted cognitive performance. Unfortunately, PET imaging revealed this was not the case.
“It is really interesting that diets enriched with omega-3 fatty acid can enhance cognition in highly functional young individuals,” says Narendarn. “Nevertheless, it was a bit disappointing that our imaging studies were unable to clarify the mechanisms by which it enhances working memory.”
Ongoing animal modeling studies in the Moghaddam lab indicate that brain mechanisms that are affected by omega-3s may be differently influenced in adolescents and young adults than they are in older adults. With this in mind, the Pitt team will continue to evaluate the effect of omega-3 fatty acids in this younger population to find the mechanism that improves cognition.
Funding from the National Institute on Drug Abuse and the American Reinvestment and Recovery Act of 2009 supported the research.
Source: University of Pittsburgh