Allergies in children may start in the gut: study
(The hill) – A new study has found that problems with gut bacteria could be behind four major — and very different — allergies in children.
More than a third of people worldwide suffer from eczema, hay fever, asthma and food allergies.
You are too increasinglywith researchers blaming everything from dietary changes to overemphasis on hygiene.
But in a study published Tuesday in Nature Communications, Canadian researchers suggested another possible cause: disruptions in the communities of tiny organisms that live in the human gut.
“Developing therapies that alter these interactions during infancy could therefore prevent the development of all types of childhood allergic diseases, which often last a lifetime,” University of British Columbia pediatrics professor Stuart Turvey said in a statement opinion.
The results suggest that all four disorders share a common cause that has long gone unnoticed, said co-author Charisse Petersen of UBC.
Because the symptoms of each condition are so different — from the shortness of breath in asthma and hay fever to the skin inflammation in eczema and the life-threatening response to food allergies — “researchers tend to study them individually,” Petersen said.
“But if you look at what’s going wrong at the cellular level, they have a lot in common.”
The research team, which became the first to track all four allergies simultaneously, followed more than a thousand Canadian children from birth to age five – about half of whom were diagnosed with one of the four allergies.
The researchers found that each disease correlated with a characteristic bacterial footprint that indicated both impaired gut lining and increased inflammation in the gut.
That points to a breakdown in the rich ecosystem of bacteria, fungi and archaea in the gut, said lead author Courtney Hoskinson of UBC.
“Our bodies normally tolerate the millions of bacteria that live in our gut because they do so many good things for our health.”
However, researchers found that, like in so many relationships, good boundaries are necessary to keep things sane.
Specifically, Hopkinson said, “Some of the species that we tolerate [the microbial community] is to maintain a strong barrier between them and our immune cells and to limit inflammatory signals that would trigger those immune cells into action.”
The breakdown of these barriers led to an increased immune response, which in turn led to inflammation — all of which accompanied the development of allergies, she added.
The scientists offered some possible risk reduction methods – but these should be viewed as population-level predictions rather than individual medical advice.
For example, Turvey said, “Taking antibiotics in the first year of life is more likely to lead to later allergic disease, while breastfeeding for the first six months is protective.”
“This was true for all allergic diseases we studied,” he added.
