Babies’ Gut Bacteria Could Predict A Future Allergy

in Food Allergy
Published: March 19, 2015

Certain bacteria in a baby’s gut can help to protect against the development of sensitivity to food, according to new research.

Scientists at the University of Alberta and the University of Manitoba investigated infants’ microbiota, the ‘good’ bacteria that live in the gut, by analyzing stool samples collected from 166 children at three months of age and again at one year. The babies then had skin-prick tests to determine if they were sensitized to any foods.

The results, published in the journal Clinical & Experimental Allergy, show for the first time that infants with more of certain strains of bacteria are less likely to become sensitized to allergens such as milk, egg or peanut.

“It doesn’t mean just because you’re sensitized at one year of age that you’re going to develop food allergy,” explains Anita Kozyrskyj, professor in the Department of Pediatrics at the University of Alberta and senior author of the study. “It’s a marker either for future development of allergic disease like eczema or asthma, and it’s also a marker of future food allergy.”

The children involved, who are now 3 years old, will be monitored until age 5 to determine how many develop full-blown food allergies.

However, more bacteria doesn’t always mean healthier children. “It’s not just the number of different bacteria, it also depends on what kind are present,” Kozyrskyj told Allergic Living. This research identified two specific groups of bacteria (Enterobacteriaceae and Bacteroidaceae) that led to higher levels of food sensitization if their levels were altered – groups that could potentially be monitored to prevent sensitization.

But what determines whether a child has more or less bacteria? The answer to that is still being discovered. Studies show, for instance, that infants delivered by Cesarean section have fewer number of different bacteria, and other factors are still being investigated.

“Anything that affects that composition in the first year of life could change the natural course of its development,” says Kozyrskyj, adding that the researchers plan to investigate what determines microbiota patterns.

Though this study is in its early stages, Kozyrskyj says that being able to understand what bacterial patterns can lead to allergic disease could lead to a more proactive approach for preventing allergies in children. The research is part of the CHILD study, an initiative financed by the AllerGen network and the Canadian government to understand the origins of allergies and asthma.