Allergic diseases like asthma, eczema, and food allergies are on the rise and many parents are keen to find ways to prevent at risk children from developing them. Studies have shown that exposure to farm animals and pets early in life can reduce the risk of developing asthma and that exposure to peanuts during pregnancy or early in life can reduce the risk of developing a life threatening allergy. Additionally, breastfeeding can reduce the risk of developing asthma. For mothers who are having difficulty breast feeding and whose baby is at risk of developing allergic disease, guidelines suggest feeding special hydrolyzed formula can help prevent the development of eczema and other allergic diseases:
“If infant formula is required in the first months of life before solid foods are introduced, there is some evidence that hydrolysed formulas may reduce the risk of allergic disease in high risk infants, with a history of allergy in their parents or siblings.” – ASCIA Guidelines
“If you need to use formula, consider a modified infant formula during the first 4 to 6 months of life. Modified formulas may reduce the risk of eczema in babies who are at increased risk of allergic conditions when compared to regular cow milk-based or soy-based formulas.” – Health Link BC
This formula is special because it has had the protein that normally causes allergic reactions to milk (Casein) broken down. A recently published study has, however, cast doubt on these infant formula guidelines in the form of a comprehensive meta-analysis. The researchers looked closely at 37 trials that compared the efficacy of hydrolyzed formula in preventing eczema, asthma, wheezing, or food allergy. The main finding of the study was that the use of hydrolyzed formulas DID NOT reduce the risk for an at risk child of developing asthma, eczema, or food allergy. Additionally, they the likely source of the incorrect conclusions from previous studies is from publication bias. Publication bias is a problem because it can skew the results and interpretation of data and influence the decision making process. In this case, many of the studies showing a benefit of hydrolyzed formula were done on a small number of patients or the experiment was improperly designed. While a study from 2006 suggested there might be a small benefit from using hydrolyzed infant formula, their meta-analysis used results from papers that are now recognized to have conflicts of interest. In particular, studies by Chandra and colleagues in the 1990’s (1, 2, 3) have come under scrutiny because of their ties to the makers of infant formula, Nestle. As such, these results are potential examples of research fraud.
In the end, the researchers in this study suggest that past results indicating a benefit to hydrolyzed infant formula are incorrect due to a couple questionable studies and small sample sizes. This current review of the data suggests that recommending hydrolyzed infant formula is no longer the right course of action and that the current policies of health care systems regarding this topic should be reviewed.