While DHA, an omega 3 fatty acid essential to brain and eye development, has been added to infant formula since 2001, in part based on research by John Colombo and Susan Carlson, the results of more recent studies on the cognitive benefits of the nutrient have been mixed.
But the two scientists, who have collaborated on examining the effects of DHA on cognitive development for 20 years, were convinced of the nutrient’s promise to boost brain development. This year, they reported a promise fufilled from the results of a seven-year clinical trial.
They found that infants who were fed enriched formula from birth to 12 months scored significantly better than a control group on several measures of cognition, language, and intelligence collected between the ages of three to six years.
The children showed accelerated development on detailed tasks requiring planning, reasoning, remembering and self-control between the ages of three to five—all of which is part of something called executive function that emerges as children mature during the preschool period.
They also scored better on two widely used standardized tests of intelligence: the Peabody Picture Vocabulary Test at age five and the Weschler Primary Preschool Scales of Intelligence at age six. The improved scores at these later ages were largely driven by verbal ability.
Many of the earlier analyses that claim no benefit for DHA are based on standardized tests administered at 18 months and even Colombo and Carlson didn’t find that children fed the omega-3 formula performed any better on the Bayley Scales of Infant Development at that age.
“Clearly, studies of nutrition and cognition should include more comprehensive and sensitive assessments throughout early childhood,” said Colombo, an expert in developmental cognitive neuroscience.
DHA or docosahexaenoic acid is an essential long-chain fatty acid that accumulates predominantly in the brain and the retina of the eye. Babies obtain it largely from their mothers before birth and from their diets after birth, but the American diet is often deficient in DHA sources such as fish, said Carlson, a nutrition scientist.