Kids with cow milk allergies have an immune system that overreacts to one or more proteins within the milk, making it difficult to digest and leading them to oftentimes miss out on important nutrients early on in infancy. A collaborate effort from researchers at the University of Chicago’s Medical Center and the University of Naples in Italy reveals how baby formula high in probiotics, like the ones found in yogurt, can improve infants’ tolerance for cow’s milk. The findings, published in The ISME Journal, come after years of research and may lead to better food allergy tolerance beyond milk in the future.

The number of children born with food allergies has increased by as much as 20 percent in the last 10 years, and being allergic to cow’s milk is the most common food allergy in infants and young children. A growing body of research finds the increase in antibiotic use, unhealthy diets that are high in fat and low in fiber, and a reduced exposure to infectious diseases, is responsible.

Previously, researchers from the University of Naples found when babies who were born with cow’s milk allergies were fed formula containing probiotic Lactobacillus rhamnosus GG (LGG), it curbed their allergy. According to the National Center for Complementary and Integrative Health, probiotics are live little organisms that help the body function properly by digesting food, destroying disease-causing organisms, and producing vitamins. Probiotics are so beneficial to the body that when infants were fed formula containing probiotics, they developed a higher tolerance for cow’s milk than babies who were fed a non-probiotic formula.

When researchers examined the bacteria community in the babies, they found a "significantly" different and healthier stomach environment for tolerating milk. These newly tolerant infants also had higher levels of bacteria Blautia and Coprococcus, which produce the fatty acid butyrate, which helps maintain balance in the gut. Researchers believe that if these specific strains of bacteria are linked with cow’s milk allergies, then maybe different bacteria strands can improve the tolerance of other food allergies.

With approximately 2.5 percent of children under the age of 3 allergic to milk, addressing cow's milk allergies was the first step to a larger approach to the public food allergy problem. Although most children eventually grow out of a milk allergy, according to Food Allergy Research & Education, some kids have such severe reactions after ingesting just a tiny bit of milk that they can be life-threatening.

"The ability to identify bacterial strains that could be used as novel therapeutics for treating food allergies is a fundamental advance," said the study’s co-author Jack Gilbert, a professor of Ecology & Evolution at the University of Chicago, in a press release. "Translating these findings into clinical treatments is our next goal."

Source: Gilbert J and Canani RB, et al. The ISME Journal. 2015.