A new study shows that early exposure of children to peanuts makes it less likely that peanut allergy will develop later. This completely reverses current medical practice where children are protected from exposure until they are at least 3 years old. But isn’t it obvious? The way infants develop protective defenses is precisely by controlled exposure, either through inoculations or through diet. If you put an infant in a bubble it will grow into a defenseless adult.
The way that researchers came to perform the study was due to an interesting observation of Jewish children. In Israel, for dietary reasons I don’t understand, early exposure is the norm. But for Israeli Jews who have migrated to the UK where that is apparently not the practice, their children have far greater incidence of peanut allergy. Now these researchers have done a large and well-regarded clinical trial that confirms this effect is not confined to Jews. They are currently extending this to other types of food allergies.
Anecdotally, I have noticed that children of previous generations seem to have far fewer food allergies than is now common in the U.S. They were not protected from potentially adverse exposures because their parents weren’t warned that it was necessary.
I suspect that this is not the only way in which well-meaning protection has unanticipated adverse consequences. Both physical and psychological problems may result from the way we often restrain children’s play and interactions.