How about 50s and 60s. Yes, there were "sensitivites" to various foods, especially milk and fish. Usually they got rashes or diarrhea. There were asthmatics who blamed cats, dogs, and flowers. No inhalers yet, they stayed at home a lot. Yes, there were a very few fat kids. In spite of mandatory PE there weren't a lot of real athletes, though. There were some mentally weird ones but the word autism wasn't even known, they were "troublemakers" who were harshly treated but didn't get better, strangely enough. I remember a couple who liked to torment animals. Some in HS who were definitely schizo. There were a few over the years in every school with permanent heart problems from rheumatic fever. I had a nasty reaction to a smallpox vaccine in 1st grade, but never met anyone else who did.