Smart or sick? Conflicting evidence on infant formula

While some researchers are reporting that babies fed with DHA-enriched formula score higher on intelligence tests, others have found that formula-fed babies may be more susceptible to chronic diseases such as obesity, diabetes, liver problems and cardiovascular disease.

A study by biochemists from the University of California, Davis have found that formula-fed infants experience metabolic stress that could make them more susceptible to a wide range of health issues.

The study, by Carolyn Slupsky and Bo Lönnerdal of the UC Davis Department of Nutrition, was published in the June issue of the Journal of Proteome Research.

“We’re not saying formula-fed babies will grow up with health issues, but these results indicate that choice of infant feeding may hold future consequences,” said Slupsky, lead author of the study and also a faculty member in the UC Davis Department of Food Science and Technology.

After four weeks of formula feeding, infant rhesus monkeys used in the trial were larger than their breast-fed counterparts, had developed distinct bacterial communities in their gut, had higher insulin levels and were metabolising amino acids differently.

“Our findings support the contention that infant feeding practice profoundly influences metabolism in developing infants and may be the link between early feeding and the development of metabolic disease later in life,” Slupsky said.

The formula-fed babies grew quickly - perhaps too quickly - which researchers link, in part, to excess protein. “You want your baby to grow, of course, but growing too quickly is not such a good thing,” Slupsky said.

But it’s not all bad news for formula-fed babies. Slupsky hopes the research will lead to the development of more beneficial formulas.

“Knowing what we now know, perhaps infant formulas that better mimic the protective efforts of breast milk can be generated,” Slupsky said.

The research team is now working on a comparison of compounds in breast milk between mothers and at different times during lactation, as well as how different formulas with varying nutrient content affect infant metabolism.

Neil Haggarty from the Fonterra Co-operative Group in New Zealand collaborated with the authors on this study. Funding was provided by the Fonterra Research and Development Centre.