A Cure for the Allergy Epidemic?
None of these scientists recommend that people consume raw milk; it can carry deadly pathogens. Rather, they hope to identify what’s protective in the milk and either extract it or preserve the ingredients during processing. Microbes may not be the key ingredient in this case. Instead, farm milk may act as a prebiotic — selectively feeding good microbes within. Another possibility is that as with human breast milk, antibodies and immune-signaling proteins in cow’s milk influence the human immune system, steering it toward tolerance.
As a whole, this research reframes the question of what prompted the late 20th-century allergy epidemic. Is the problem one of exposure to allergens, many of which aren’t exactly new to human experience? Or is the problem one of increasing sensitivity to whatever allergens are present?
The science suggests the latter. The Mast cowshed, with its rich array of microbial stimuli, probably resembles the world in which the human immune system evolved more than, say, an apartment high above Manhattan. The Amish in Indiana, who for reasons of religious faith have maintained a 19th-century-like lifestyle, may not be less allergic. Rather, during the dramatic reordering of human existence that began with the Industrial Revolution, everyone else may have become more allergic. Immunologically speaking, the farming Amish and farmers generally may more closely resemble an evolutionary norm for our species.