Basically after populations are treated for parasites (in 3rd world countries) the rate of autoimmune diseases goes up. It's thought that since the immune syst

Basically after populations are treated for parasites (in 3rd world countries) the rate of autoimmune diseases goes up. It's thought that since the immune system has nothing to do, it starts attacking itself which makes sense from an evolutionary stand point. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1618732/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1618732/