Autoimmune disease has increased sharply in the last 50 years. While genetics is a variable, the rise in AI diseases totally outpaces changes to the human gene pool. This great NYT article reviews two studies that suggest that an infant’s microbiome-or lack of development of the microbiome-can predict AI. Findings are preliminary, but circle us back to the hygiene hypothesis—that is, we need exposure to bugs, especially when we’re small– to stimulate and balance the immune system. A balanced, robust immune system controls for the hyper-reactivity associated with autoimmunity and allergic disease.
Once again, we’re reminded that a little dirt will do ya!
Incidentally, there is very interesting, new research out on the skin microbiome and establishing tolerance to those microorganisms. Again, it appears to happen in early infancy and once the window is closed, vulnerability to developing immune mediated diseases may increase (animal study).