Peanut allergies. In the 1950's, were school children occasionally carted off from the lunchroom experiencing.....

[Phoenix61]

10. Peanut allergies have tripled.

“For example, one theory, called the hygiene hypothesis, highlights how the way people who live in developed countries may have an impact on childhood allergies, including peanut allergies. Babies born in developing countries have lower incidence of allergies than those in developed countries. But if a family moves to a more developed country, their children’s incidence of childhood allergies increases. So simply being in the environment of a developed country seems to change things.

The hygiene hypothesis suggests that children who have more exposure to germs and certain infections at a very early age develop immune systems that are better suited to differentiating harmless substances from harmful substances. In this theory, exposure to certain germs teaches the immune system not to overreact. It would also explain why children who grow up on farms or those who have certain types of pets are less likely to develop allergies than other children. But much more research is needed to understand exactly how childhood germ exposure might help prevent allergies”.

https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-q-and-a-number-of-children-with-peanut-allergies-has-increased-significantly/

Guess drinking out of the garden hose and kissing the family pets was a good thing.