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Children could be set on a path to developing allergies, asthma and eczema before they are born.
Analysis of a baby’s first stool, known as meconium, shows that a lack of certain biochemicals and gut bacteria normally seen in the faeces is linked with a higher risk of allergies and other conditions.
Allergic conditions such as food allergies, hay fever, asthma and eczema are caused by the immune system overreacting to harmless compounds in the environment. Many studies have found links between such immune system reactivity and a lower diversity of gut bacteria, or microbiome. One idea is that a diverse ecosystem of beneficial bacteria helps to “train” the developing immune system to tolerate non-harmful compounds.