Data from the POSGRAD (Prenatal Omega-3 Fatty Acid Supplementation and Child Growth and Development) study, published in the American Journal of Clinical Nutrition, indicated that prenatal supplementation at a dose of 400 mg DHA per day was associated with improved sustained attention in the children at age five.
“We present evidence of a beneficial effect of prenatal supplementation with DHA on objective measures of attention and executive function at preschool age,” wrote the authors, led by Usha Ramakrishnan from Emory University in Atlanta, GA.
“Children whose mothers received DHA during pregnancy committed fewer omissions than those in the placebo group. These results are consistent with evidence from animal models and biological evidence linking DHA to functions of the prefrontal cortex such as responsiveness and sustained attention.”
Omega-3s and cognitive function
The study adds to the scientific literature on the potential effects of omega-3 fatty acids in the cognitive function of children. Results to date have been mixed with some studies reporting benefits, and others reporting no effects.
Since DHA is an important constituent of the brain there is biological plausibility for the potential benefits.
The new study included 1,094 Mexican women randomly assigned to receive DHA (DSM/Martek Biosciences) or placebo from the 18th 22nd week of pregnancy until birth of their child. The researchers were then able to assess data from 797 of the children at age five.
The study’s authors were affiliated with: Emory University (USA); the National Institute of Perinatology (Mexico); Georgia State University (USA); the National Institute of Public Health (Mexico); and the Global Alliance for Improved Nutrition (Switzerland).
The study was funded by a grant by the US National Institutes of Health and the March of Dimes Foundation.
Results showed that, while there no significant differences between the groups for general cognitive function and behavior, a significant improvement in attention was observed in the DHA children.
“There is evidence that the benefits of improving nutrition during the first 1000 d of life on cognitive outcomes may not become evident until children start school and are more challenged by the environment,” wrote the researchers. “The long-term significance of our current findings and impact of the POSGRAD intervention on cognitive and behavioral functioning during the school years remains to be determined.”
Commenting independently on the study’s findings, Harry Rice, PhD, VP of regulatory & scientific affairs for the Global Organization for EPA and DHA Omega-3s (GOED), told us: “While the results peek my interest and definitely make a contribution to the science, it's unfortunate that the investigators didn't measure omega-3 (i.e. DHA) status in both the mothers and offspring. This may have presented the greatest opportunity to detect a robust benefit. The prevailing belief seems to be that the most significant benefit(s) are seen in individuals with low omega-3 status that respond to supplementation.
“In this study, it would have been interesting to learn if the offspring from supplemented mothers had a collectively higher DHA status and if greater benefits were demonstrated in children of higher DHA status. As far as I'm concerned, all future omega-3 intervention trials should include measurements of omega-3 status.”
Source: American Journal of Clinical Nutrition
Published online ahead of print, doi: 10.3945/ajcn.114.101071
“Prenatal supplementation with DHA improves attention at 5 y of age: a randomized controlled trial”
Authors: U. Ramakrishnan et al