Children can have a whole host of allergies that afflict them—from eczema, food reactions, asthma and hay fever—but different as they appear to be, they could all have a common origin.
They could all start in the gut and the community of bacteria—the microbiome—that live there, say researchers from the University of British Columbia.
They tracked the health of 1,115 children from birth until the age of five. More than half the children developed one or more allergies in that time, and stool samples were taken to understand what was going on in the gut.
The samples from the allergic children displayed a bacterial signature that was quite different from the healthy children. It showed signs of dysbiosis—an indication of an imbalanced gut microbiota—that can lead to a compromised intestinal lining and inflammation.
Some of these markers were seen in samples from babies, even before they started showing signs of an allergy.
One of the key culprits for gut dysbiosis is antibiotic drugs, while the children who were breastfed at least for the first six months of life had better gut protection, the researchers said. Antibiotic usage and breastfeeding were “universal to all the allergic disorders we studied,” said Stuart Turvey, one of the researchers.