The fatty acids, called docosahexaenoic acid (DHA) and arachidonic acid (ARA), begin accumulating in the fetal brain around the sixth month of pregnancy and are in a mother's breast milk, says Susan Carlson of the University of Kansas Medical Center, one of the researchers involved in studies of the compounds.
"They are an incredibly important part of the central nervous system, and without them the visual system is compromised," she says.
There's also increasing evidence that higher amounts of DHA and ARA improve how babies process information, she says.
While the additives have been sold in baby formula for the past five years in 60 countries, the U.S. Food and Drug Administration (FDA) only recently approved them for sale here.
The formulas, called Enfamil LIPIL and Similac Advance, are manufactured by Mead Johnson Nutritionals and Ross Products, respectively, and are now available nationally, both companies say.
"We've sold Enfamil LIPIL in Hong Kong for two years, and now 75 percent of the moms have switched to it from regular Enfamil with iron," says Mead Johnson spokesman Pete Paradossi. "It has the appropriate levels and ratios of each compound to enhance visual and mental development."
Carlson, a nutrition professor at the University of Kansas, has long believed that DHA and ARA were needed for optimal development in premature infants who did not have the chance for the fatty acids to accumulate in their brains before birth.
In studies of pre-term and term infants over the past decade, Carlson found that the addition of DHA and ARA to the babies' diets was of great value.
"The benefits are better earlier vision function and better processing of information," says Carlson, who conducted the research with colleague John Colombo, a behavioral psychologist.
In one study, the researchers found that infants who had received DHA in their formula looked at pictures for a fraction of a second less than infants who did not, which was significant, Carlson says.
"The babies that took longer are processing the information more slowly, and looking for longer periods of time is associated with lower performance," she says.
Interestingly, Carlson says, American women have the lowest levels of DHA and ARA in their breast milk of any women in the world. The average level of DHA and ARA in American women's milk is 0.1 percent of the total of milk fatty acids, compared to 0.22 percent in Europe, 0.71 percent in China, and 0.90 percent in both Malaysia and India.
"Women in other cultures eat more fish," Carlson says, and that's the source for the essential omega fatty acids that are converted into DHA and ARA.
Carlson and her colleagues are now studying 70 infants born to women whose DHA status was known during pregnancy and at the end of pregnancy. Their aim is to discover whether the level of DHA in mothers' milk is associated with aspects of their infants' development.
The study was initiated with a grant from the University of Kansas Medical Center Research Institute and is funded by Omega Tech Inc., of Boulder, Colo. which produces high-DHA eggs.
What To Do: For advice on prenatal care, you can visit The Nemours Foundation. Information about Enfamil LIPIL can be found at Mead Johnson Nutritionals. For more on Similac Advance, visit Ross Products.