Infant formula appropriateness pediatric nutrition

Nutrition Research Newsletter, August, 2005

Allergy to cow milk protein occurs in 2% to 3% of infants. Approximately half of these infants begin to tolerate cow milk by the age of 2 years. Following weaning from breast milk, infants with cow milk allergy (CMA) are usually given either an extensively hydrolyzed formula or a soy formula. Eight to 14 of infants with symptoms of immunoglobulin E-associated CMA also react adversely to soy, but reports of anaphylaxis to soy are rare.

The goal of a recent study was to compare the effects of a soy formula or an extensively hydrolyzed whey formula on the nutritional status of infants until age 2 years, and on their growth until age 4 years. The study involved 168 infants with CMA. The allergy was confirmed by a double-blind, placebo-controlled milk challenge. At inclusion in the study, the symptoms that occurred most often in the infants because of CMA were atopic eczema (59%) and gastrointestinal symptoms (22%). When CMA was confirmed, the infants were allocated to groups that received either a soy formula or an extensively hydrolyzed whey formula according to a computer-generated block randomization list; a block size of 4 was used.

The length--SD score--of the infants was close to the mean Finnish reference growth by age 2 years in both groups. Weight-for-length measurements continued to reach the 50th percentile by age 4 years, in both study groups. The mean nutrient intake followed the recommended intake in both groups, although most of the infants were supplemented with calcium and vitamin D. The observed serum transferring receptor concentrations indicated a greater iron inadequacy in the tissue of infants in the soy formula group than in the hydrolyzed whey formula group (P = 0.08). However, there were no significant differences between the groups either in the percentages of abnormally low laboratory values (mean cell volume, hemoglobin, zinc, and ferritin) or in the percentages of high alkaline phosphatase activity, which indicates the comparable safety and effectiveness of the formulas studied.

Both nutritional status and growth were within reference values in the 2 groups. It seems that the selection of a formula can largely be made on the basis of infant tolerance to the formula.

L. Seppo, R. Korpela, B. Lonnerdal, et al. A Follow-Up Study of Nutrient Intake, Nutritional Status, and Growth in Infants with Cow Milk Allergy Fed either a Soy Formula or an Extensively Hydrolyzed Whey Formula. Am J Clin Nutr; 82:140-145 (July, 2005). [Correspondence: L Seppo, Foundation for Nutrition Research, PO Box 30, Helsinki FIN-00370, Finland. E-mail: leena.seppo@valio.fi]