Hygiene Hypothesis

The hygiene hypothesis proposes that less early-life exposure to microbes increases allergic disease. Applied to eczema, it is one explanation for why early dog ownership is associated with less atopic dermatitis (Pelucchi 2013 lists it as a keyword). Dogs and cats change the bacteria found in homes, which may affect immune development or the skin microbiome (Ownby & Johnson 2011). This remains a hypothesis, not established mechanism.

Connections

• Pets and Eczema — proposed explanation for dog protection, source: Ownby & Johnson 2011