Infant formulas not all equal

Infants fed different infant formulas can develop significantly different levels of bone mineral content and bone mineral density - key indicators of bone strength - according to a new US study.

The study, which appears in the May issue of Pediatrics​ - the official journal of the American Academy of Pediatrics - was conducted at Hutzel Hospital at Wayne State University in Detroit, Michigan in the US and examined the difference in bone mineral content and density in children who had received infant formula containing palm olein oil as compared to those who received infant formula without the oil.

"Our research showed that babies develop significantly greater, more favourable levels of bone mineral content and density when fed an infant formula without palm olein oil than when fed a formula containing that oil,"​ said Winston W. K. Koo, professor of paediatrics at Wayne State University and author of the study.

"Infancy is an especially critical time to be building bone because bone mass increases at its fastest rate during the first year. How bones develop during this period and throughout childhood can potentially affect bone health for life,"​ Dr. Koo stated.

"Breast feeding is still the best way to go,"​ continued Dr. Koo. "But for babies who are not breastfed, our study showed that not all infant formulas are the same, even if their nutritional content is essentially the same on the label. There are important differences in the selection of ingredients that significantly influence calcium absorption and bone mineralisation."​

The two infant formulas compared in the study - Enfamil with iron produced by Mead Johnson Division of Bristol Myers and Similac with iron by Ross Products Division Abbott Laboratories - had the same level of calcium, but had differences in key ingredients including the oil blend and type of calcium salts used. The key difference here was that Enfamil contained Palm Olein oil while Similac did not.

"When evaluating an infant formula, you need to consider the whole nutrient matrix. We knew from research reported by others that a palm olein-free infant formula had an advantage in calcium absorption. Our new clinical evidence linked this formula's greater calcium absorption to a greater increase in bone mass, and that likely means stronger bones,"​ Dr. Koo said.

Whole-body bone mineralisation was determined by dual energy X-ray absorptiometry, a technique that scans the body to measure bone mineral content and density.

"This sophisticated instrumentation helped make our findings possible,"​ Dr. Koo said. "Bone mineralisation cannot be determined simply by looking at someone. On physical examination there were no differences in the infants' weight, length and head circumference over the course of the study. But our instrumentation provided a new window on what was happening in the development of bone within the babies' bodies."​

Funding for the study was provided by Abbott Laboratories' Ross Products Division of Columbus, Ohio in the US, a manufacturer and marketer of paediatric and adult nutritional products including the Similac line of infant formulas.