Data published in Nutrients indicated that omega-3 index – a quantification of the fatty acid status of a person – were significantly associated with information processing speeds and that every 1% increase in the Omega-3 Index was linked to a 1.23 digit increase on the Letter Digit Substitution Test (LDST).
“Also, students with a higher Omega-3 Index had fewer errors of omission on the D2 test of attention, an indicator of inattention/impulsivity (i.e., they paid more attention than students with a lower Omega-3 Index),” wrote scientists from the Open University of the Netherlands, Omegametrix (Germany), Aker BioMarine (Norway), and Maastricht University (The Netherlands).
“To our knowledge, this is the first study assessing the association between the Omega-3 Index measured in blood and cognition in typically developing adolescents from the general population.”
“Some much needed insight”
Commenting independently on the study Harry Rice, PhD, VP of regulatory & scientific affairs for the Global Organization for EPA and DHA Omega-3s (GOED), told us: “Given the couple of positive associations between the O-3 Index and cognitive measures, the results from the supplementation could provide some much needed insight in this area of research.
“One thing is for certain: The children in this study need to increase their EPA/DHA intake, if not for cognitive reasons, then for cardiovascular reasons. Their O-3 Index scores are way too low.”
Led by Inge van der Wurff, a PhD candidate at the Open University of the Netherlands, the used baseline data from Food2Learn, a double-blind and randomized placebo controlled krill oil supplementation trial in 13-15 year-old Dutch adolescents.
Blood samples were taken from 266 teens and used to calculate the Omega-3 Index, and cognitive performance was assessed using a battery of different tests.
Results showed that the average Omega-3 Index was 3.83%. “The Omega-3 Index (3.83%) in this sample was relatively low (well below the recommended range of 8%–11%),” wrote the researchers. “This could be due to the exclusion of participants with a high Omega-3 Index, although if these were included the mean was still only 3.89. The low Omega-3 Index in this sample is no surprise since 13.9% of the students did not consume any fish and 77% consumed fish rarely, as measured by the fish consumption questionnaire.”
Crunching the numbers showed that a higher Omega-3 Index was associated with higher scores on the LDST and fewer errors on the D2 test of attention, which measures selective attention. No associations were observed in the other seven cognitive measures, added the authors.
“The results of the supplementation study will further elucidate the effect of LCPUFA supplementation on cognition,” they wrote. “If a positive effect of LCPUFA supplementation on cognition is shown, this could help improve cognitive functioning and possibly the school performance of adolescents in a relatively inexpensive and easy way.”
Low levels among Americans, too
The Omega-3 Index has also been linked to heart health and a recent paper by scientists from DSM Nutritional Products, the University of British Columbia, and Cornell University highlighted this issue, and raised concerns for the American population.
Data published in Nutrients (2015, Vol. 7, No. 12, pp. 10282-10289, doi: 10.3390/nu7125534) indicated that 95.7% of a nationally representative sample of Americans has an omega-3 index below 4%, reported to be a high risk indicator for coronary heart disease.
“Suboptimal [long-chain omega-3 polyunsaturated fatty acid (LCn-3 PUFA)] concentrations are common among U.S. adults despite repeated emphasis on increasing seafood consumption,” they wrote.
“Hispanic individuals and individuals aged 20 to 59 may be particularly important populations to focus on given the high prevalence of suboptimal LCn-3 PUFA. Notably, no subpopulation had a majority of individuals with LCn-3 concentrations above suboptimal, thus highlighting the need for improving LCn-3 PUFA levels in the food supply.”
2016, Volume 8, Number 1, 13 doi:10.3390/nu8010013
“Association between Blood Omega-3 Index and Cognition in Typically Developing Dutch Adolescents”
Authors: I.S.M. van der Wurff, et al.