I’ve always wondered about peanut allergies. When I was a kid, nobody ever heard of a peanut allergy. Heck, our favorite day of the week was Thursdays — when the cafeteria served honey and peanut butter sandwiches. Mmmm. What a delicasy.

My childrens’ school is filled with peanut allergy kids. They haven’t been in one class that didn’t contain at least one child with a peanut allergy. It’s serious stuff. These kids can’t be exposed to any form of peanuts. If some parent messes up and sends a kid to school with a Reeses Pieces or some peanut butter Nabs in his bookbag, his classmate could die. At least, that’s how they make it sound in these serious letters we get at the beginning of the year.

So, anyway, I’ve often wondered what happened over the last generation that created this peanut allergy epidemic. Here are a couple of guesses, according to a WSJ article:

The number of children with peanut allergies has skyrocketed, doubling from 1997 to 2002, according to a study in the Journal of Allergy and Clinical Immunology. And it’s a mystery why peanut allergies are causing more problems. One explanation is that physicians are more adept at detecting them. Another is that the modern environment may be, in a sense, too clean: If the human immune system were exposed to more allergens, a peanut might not send it into overdrive.

The latter makes much more sense. That’s why I never washed my kids pacifiers after they dropped on the floor. Nope, just picked ’em up and handed ’em back.

And my kids can eat peanut butter by the bucket.