Most cow’s milk formulas do not raise risk of Type 1 diabetes

Lisa Foster-McNulty, MSN, RN, CDE

Breast milk is still considered to be the best source of nutrition for babies, but there are various circumstances where it becomes necessary to give formula to a newborn.  A study published online on January 17, 2017 in Diabetes Care suggests that most cow’s milk formulas do not up the risk of developing Type 1.  However, German researchers found that giving highly hydrolyzed formula within the first seven days of life can increase the chance of Type 1 for some children.  This type of formula is sometimes recommended for babies with food allergies.  Lead study author Sandra Hummel from the Institute of Diabetes Research in Munich indicated that there is no benefit for infants at increased genetic risk for Type 1 to be given hydrolyzed formula as the first infant formula when it isn’t possible to breast feed.

In this study, regular cow’s milk formula, partially hydrolyzed formula, and even highly hydrolyzed formulas weren’t linked to a higher risk for Type 1 diabetes when given in the first three months of life.  However, when highly hydrolyzed formulas were given in the first seven days after birth, the chances of islet autoimmunity went up 57%!

Highly hydrolyzed formulas contain cow’s milk proteins which are not whole; they are already at least partially broken down.  The molecular weight of cow’s milk protein varies by formula, with it being heaviest for standard formulas and lightest for highly hydrolyzed formulas.  Standard formula is less costly than the partially or highly hydrolyzed formulas.   

Bear in mind that Type 1 is believed to be caused by more than just one factor.  And this study wasn’t structured to prove a cause-and-effect relationship between the use of cow’s milk baby formula and the development of autoantibodies that can trigger Type 1 diabetes.  This is just one piece of the puzzle.

Past studies on the effect of cow’s milk on the subsequent development of Type 1 have yielded mixed results, so it is still unclear as to whether or not there is a connection, according to the study authors. 

This study used data from a long-term study of children who have a high risk for developing Type 1.  They were followed from birth through age eight.  Included are nearly 9,000 children with a gene that indicates an increased risk of Type 1 diabetes.  The children come from the United States, Finland, Germany, and Sweden.  Eighty percent of the extensively hydrolyzed formula use occurred in Finland.  Even after accounting for this, the researchers still saw a link.

Researchers think there are a number of possible reasons why highly hydrolyzed formulas might increase the risk of developing Type 1.  It may be related to early immune system education, or it could be the microbiome (bacteria normally living in the intestines) of the gut.  If there is a history of Type 1 diabetes in the family, parents should speak to their pediatrician in advance about what type of formula would be best to use in the event that formula is needed.