June 25, 2019
Leave your preconceptions about the word 'bacteria' at the door: a new study suggests the recent increase in food allergies in young people across the country could be reversed with the presence of more bacteria.
Scientists at Boston Children's Hospital and Brigham and Women's Hospital published a study in the journal Nature Medicine this week, in which the authors say our increasingly sanitized society is actually causing the uptick in food allergies.
Nearly 8 percent of children in the United States are affected by food allergies, a sharp rise from a decade ago, according to the American Association for the Advancement of Science. The authors of the study hypothesized that certain lifestyle changes, including increased use of antibiotics, were leading to the increase.
The authors tested this idea by studying gut bacteria in infants with food allergies, and infants without food allergies. By studying stool samples from both groups, the researchers were able to determine a difference in the samples' bacterial makeup, according to the AAAS.
To determine what role the different bacteria played, the researchers ran an experiment: they transplanted the bacteria into allergy-prone mice. When the different bacteria were introduced, the bacteria from food-allergic babies didn't protect the mice against food allergies, while the bacteria from babies without food allergies was successful.
The team of researchers then dug deeper, looking at the successful bacteria samples. They found bacteria from the order Clostridiales was present, which had previously been noted as bacteria potentially successful in protecting against food allergies. In a subsequent test similar to the first, the researchers found both Clostridiales and Bacteroidales bacteria were successful in suppressing allergic reactions.
"The loss of these bacteria acts as a switch that makes children susceptible to food allergy," Dr. Talal Chatila, director of the Food Allergy Program at Boston Children's and a senior author on the study, told the AAAS.
Chatila said he believes this study should provide a "fundamental concept" of how food allergies come about, which researchers can use for future treatments.