There's actually pretty good evidence now that childhood sanitation is correlated with the incidence of Acute Lymphoblastic Leukemia (ALL). Edit: accidentally w

There's actually pretty good evidence now that childhood sanitation is correlated with the incidence of Acute Lymphoblastic Leukemia (ALL). Edit: accidentally wrote inversely Here is a pretty good overview: https://www.medscape.com/viewarticle/897242 https://www.medscape.com/viewarticle/897242 Note that this is a little different than the usual interpretation of the hygiene hypothesis.