Pregnant woman
Photo: Wikimedia Commons

The unique composition of a mother’s breast milk could play a role in reducing infant food allergies, UC San Diego researchers announced Tuesday.

The study, conducted in collaboration with Canadian researchers, focused on human milk oligosaccharides, also called HMOs. Not found in infant formula, HMOs are the third most abundant solid component to breast milk, following lactose and fat.

The sugar molecules aren’t digested, but instead guide development of infant gut microbiota, which previous research suggests strongly influences allergic disease.

With data and milk samples from 421 infants and their mothers, researchers found that 14 percent of kids displayed sensitization to one or more foods at age 1. Sensitization doesn’t necessarily indicate an allergy, though it is a strong predictor.

HMO composition appeared to play a role in which infants developed food sensitization, said Lars Bode, associate professor of pediatrics at UCSD’s School of Medicine. The individual composition of breast milk HMOs is determined by a variety of factors, including lactation stage, gestational age, maternal health, ethnicity, geographic location and breastfeeding exclusivity.

“Our research has identified a beneficial HMO profile that was associated with a lower rate of food sensitization in children at one year,” Bode said. “To our knowledge, this is the largest study to examine the association of HMOs and allergy development in infants, and the first to evaluate overall HMO profiles.”

Additional research should determine underlying biological mechanisms, scientists said, and whether HMO modification may be used to therapeutically reduce food allergies.

The recent study was based on milk samples taken three-to-four months after birth then analyzed at UCSD. Later, 1-year-old children were given skin prick tests to determine sensitivity to common food allergens.

Participants were already part of the CHILD Study, launched in 2008 by the Canadian Institutes of Health Research and the AllerGen Network of Centres of Excellence to track nearly 3,500 Canadian mothers and children from pregnancy to school age.

–City News Service