More evidence that the key to allergy-free kids is giving them plenty of dirt – and cows — The Washington Post

I’m not saying you should let this cow lick  your baby, but … (Boris Roessler/DPA via AFP)

People who grow up on farms — especially dairy farms — have way fewer allergy and asthma problems than the rest of us. Now one research team thinks they’ve brought science closer to understanding why.

In a study published Thursday in Science, researchers report that they were able to pinpoint one possible mechanism for the allergy protection in mice they studied. Surprisingly, the protein that they fingered as the likely allergy-preventer doesn’t actually affect the immune system — it affects the structural cells that make up the lining of the lung.

The research is related to something called the hygiene hypothesis, where a lack of exposure to microbes as a tyke leads to more allergy and asthma. It’s what leads microbiologists to say that the best thing you can do for your kid is roll them around on the floor of the subway. That may indeed be true (as long as you roll very, very carefully!) but there’s increasing evidence that farms have the best germs for preventing respiratory problems and allergic reactions later in life. One study found that just 25 percent of children living on Swiss farms reacted to common allergens like dust mites, pollen, animals  and mold, while 45 percent of children in the general population reacted.

An estimated 50 million Americans suffer from seasonal allergies. Here’s what happens when things like grass, pollen, trees and molds affect your body. (Jhaan Elker, Osman Malik and Jorge Ribas/The Washington Post)

And among Amish children — who obviously have some of the farmiest of farm lives, though other factors may also be at play — reactions fall to a shocking 8 percent or less.