Meconium, microbiome and allergies. What’s the connection?
Meconium is no ordinary stool. It contains various substances that have entered the digestive system of the fetus during their stay in the womb. Among its standard components are amniotic fluid, fetal skin cells, and skin secretions. In addition, it contains many substances due to the mother’s diet. Its composition may indicate what acted on the fetus during its development. In addition, it provides scientists with information on what influences the formation of the human gut microbiome early in life.
“Meconium is a kind of time capsule that demonstrates what acted on the fetus before it was born. These substances then become the primary food source for the earliest bacteria in the gut, ”explained Professor Charisse Petersen of the University of British Columbia, co-author of the new study. She added that the more varied the composition of meconium, the richer the gut microbiome with different types of bacteria.
It was previously known that the risk of developing allergies and bronchial asthma is associated with a low diversity in the composition of the gut microbiome. There is a hypothesis that the diversity of bacteria “trains” the human immune system to carry various harmless substances. Accordingly, it reduces the likelihood that the immune system will be triggered in response to food or plant pollen, as is the case with allergies.
What the new study showed
In a new study, Canadian scientists analyzed meconium from 100 newborns. Then they compared the data on its composition with the risk of developing allergies by the first birthday of children.
In a quarter of the children examined, meconium, which had the most chemically diverse composition, was twice as likely to develop allergies after 12 months as in the rest. Likewise, the greatest diversity of bacteria is found in meconium and the subsequent risk of allergies.
Using artificial intelligence, scientists were able to predict the risk of developing allergies in children with an accuracy of 76%. Petersen noted that the results of the study show how intrauterine factors influence the formation of the immune system.
“We know that children with allergies are more likely to develop asthma. We now have the ability to identify children at increased risk who may benefit from early medical intervention, even before the first symptoms of allergies and asthma appear, ”said Stuart Turvey of the University of British Columbia, study co-author.