[Amelia]

So it's possible that in years past, before soy formula was available, the babies might have died from "failure to thrive" and wouldn't have become allergic to peanuts?

[Pharmboy]

Well, before soy formulas were available--in the 1950s--there were other modified easy-to-digest formulas based on pre-digested mild protein. Also, banked breast milk or wet-nursing was used for these intolerant infants. The soy-based formulas (Isomil and others) were important advances in infant feeding (although certainly over recommended) and they might have the effect of increasing certain food allergies later on.