Allergies are a form of immune response to normally innocuous things.
It makes sense that there is general coincidence between severe allergies and other immune disorders.
It makes sense that there is general coincidence between severe allergies and other immune disorders.
ngl i think this is just a epigenetic shift from people who have been "raised weak" for several generations. i can't prove it completely but there is some research showing that kids with milk allergies end up runty:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4362703/
https://www.jacionline.org/article/S0091-6749(19)31475-7/ful...
By the way, the two worst offenders i ever met when talking about allergies were around the same age (they should be in their 60s now) and both are Distilben babies. And they were scrawny, but it wasn't by choice, they just couldn't eat most fats. Nothing to do with nurture in their case.