Twenty-two months after the publication of a landmark trial, a panel of experts enlisted by the NIH’s National Institute of Allergy and Infectious Diseases has issued adjusted clinical guidelines on the prevention of peanut allergies in children. The new approach (here’s a more accessible summary for parents and caregivers) is essentially a reversal of accepted practice for the last several decades—which was to keep infants who show a tendency toward allergies away from the common trigger. Now, with some caveats, allergy specialists and parents are being encouraged to give tiny amounts of peanut-containing foods (extract or powder) to their infants when they are as young as four to six months old, in some cases.

There is, it would now seem, “a window of time in which the body is more likely to tolerate a food than react to it,” Dr. Matthew Greenhawt, a food allergy expert, told the New York Times. “And if you can educate the body during that window, you’re at much lower likelihood of developing an allergy to that food.”

The Times and others have good summaries of the 2015 “LEAP trial,” which involved more than 600 allergy-high-risk infants and which led to this change in practice. But reading the new guidelines alongside the old 2010 guidelines is a good exercise in seeing how easily a paradigm shift in healthcare can occur.

The latest report is also a reminder of how far we still have to go in preventing and treating food allergies across the board, which typically begin in childhood and can last a lifetime—causing millions of people to live snack-to-meal in a constant state of vigilance.

As many as 6% of children in the U.S. report a food allergy, a figure that has been steadily and inexplicably climbing for decades (sorry, this last paper is behind a paywall). The costs—both in ER visits due to anaphylactic reactions and in human psychic burden—are immense and growing, too. Eight foods—milk, eggs, peanuts, tree nuts, fish, shellfish, soy, and wheat—account for 90% of food allergies, but as the CDC acknowledges, “the mechanisms by which a person develops an allergy to specific foods are largely unknown.”

The good news is, there is at last some investor interest in this area. In November, for instance, Nestle put a hefty $145 million stake in Aimmune Therapeutics, a U.S. biotech, which is in late-stage trials on a peanut-allergy desensitization treatment.

I’ll be at the big J.P. Morgan Healthcare Conference next week looking for more innovation on this and other fronts. Email me if you think there’s something I should see.