Peanut allergies. In the 1950's, were school children occasionally carted off from the lunchroom experiencing.....

[Aristus]

20. Until the late 1990's, the prevalence of peanut allergies in the pediatric population was about 0.6%.

Then a study was published in (I think) the British Medical Journal reiterating the severity of peanut allergies, and wrongfully recommending keeping infants and toddlers away from peanuts at all costs, which is the opposite of how one prevents hypersensitive allergen reactions, which is gradual exposure in increasing amounts.

The percentage of peanut allergies exploded to the point that by about 2008, the prevalence of allergies among children was close to 50%. Certainly the sale of Epipens went through the roof.

Allergists have known for decades that the way to prevent allergic reactions was by gradual exposure to the allergen, not total prohibition. Babies who play around in the dirt and mud get far fewer allergies as they grow than babies who are restricted to near-sterile conditions as their systems develop.

No one is quite sure why the medical community got this one wrong, but we’ve been working to reverse the damage. For newborns who are breast-feeding, offering a tiny amount of creamy peanut butter in-between feedings, increasing the amount gradually, is the way to go.