Supplements during pregnancy, DHA promotes the development of lean mass in children

Following DHA supplementation during pregnancy can influence the body composition of the children to be born, suggesting that a maternal diet rich in omega-3 may have beneficial effects on the fetus that extend into early childhood. Mothers who consumed daily supplements containing 600 milligrams of DHA during pregnancy are more likely to have children with greater lean mass at five years of age compared to those who did not follow the supplementation.

The study, published in The American Journal of Clinical Nutrition, was conducted by a team of researchers from the University of Kansas (USA), led by Professor Susan Carlson.

Polyunsaturated fatty acids help proper fetal development

The omega-3 DHA and omega-6 Arachidonic Acid are the main long-chain fatty acids in cell membranes and are involved in the proper development of the fetal nervous system. Both are essential nutrients as they play an important role in controlling inflammation and in the differentiation of stem cells. During fetal development, a particular type of cells called mesenchymal stem cells will give rise to various tissues such as adipose tissue and muscle tissue. This critical growth period has long-term implications and is fundamental for good health during growth, since the number of muscle fibers is set at birth.

Considering also that DHA inhibits the differentiation of fat cells, it is likely that the reduction of the maternal Arachidonic Acid to DHA ratio may influence body composition in childhood, regulating the percentage of lean mass and fat mass in the child. Fat mass is represented by adipose tissue, which consists of specialized cells, adipocytes, that store triglycerides, while lean mass represents the remaining portion of the body, which thus includes water and muscles.

Previous studies have shown that infant formula containing DHA and Arachidonic Acid increases lean mass and reduces fat mass in 1-year-old preterm infants, demonstrating that omega-3 in the very early stages of fetal development can influence body composition. More recent studies have found an association between intrauterine DHA exposure and offspring body composition during childhood, showing higher lean mass or a lower percentage of fat mass.

Pregnancy supplements: DHA may influence body fat and child health

The new study investigated the effect of DHA-based pregnancy supplements on lean and fat mass, showing that the use of supplements during gestation was associated with a higher likelihood of having children with a higher percentage of muscle tissue compared to children born to women who did not follow the treatment. According to the researchers, this result demonstrates that increasing maternal DHA intake through pregnancy supplements can have beneficial effects on the fetus that extend into childhood. As stated by Professor Carlson, "DHA can be delivered to the fetus by increasing maternal consumption during pregnancy and breastfeeding."

This suggestion is especially important considering that omega-3 intake in the general population is rather low in many industrialized countries. According to a co-author of the study, Professor Colombo, this study has two important implications: the first concerns the effects of DHA, long associated with proper visual, cognitive, and behavioral development in early childhood, but now also seeming to promote leaner growth and healthier children.

The other important implication of these results is that the conditions to which the fetus is exposed during pregnancy can influence the child’s physical characteristics up to nearly six years later. This further confirms scientific research in development that has been gathering evidence on how the prenatal environment can have long-term effects on growth and how a person’s life can be strongly influenced or determined by what happens before birth.

Study details

To conduct the research, the team involved approximately 360 pregnant women with low-risk pregnancies living in the Kansas City area between March 2006 and September 2009. Half of the participants were randomly assigned a prenatal supplement containing 600 milligrams of DHA, while the others were given a placebo. Five years later, children born from those pregnancies were examined with very accurate methods assessing body weight, height, BMI (Body Mass Index), fat mass weight and fat-free mass weight, and their percentages.

The team found that children whose mothers consumed DHA during pregnancy had about half a kilo more lean mass on average and the same amount of fat compared to the placebo group. No significant evidence was found for the effect of DHA supplements during pregnancy on the other measures collected.

A mechanism yet to be clarified 

The research results highlighted a link between DHA supplementation during pregnancy and the percentage of lean mass in 5-year-old children, confirming data from a previous study conducted in the United Kingdom. Although the mechanism underlying this result is not clear to the researchers, it is known that the ratio between omega-3 and omega-6 fatty acids in early development may influence the balance between muscle and fat cells in accordance with the hypothesis that the number of muscle fibers is already set at birth.

Source: Brandon H Hidaka, et al “Intrauterine DHA exposure and child body composition at 5 y: exploratory analysis of a randomized controlled trial of prenatal DHA supplementation” The American Journal of Clinical Nutrition, Volume 107, Issue 1, 35–42.