Yes, low priors for Jayman's hypothesis. Although it wasn't sufficiently specified what exactly his hypothesis was, so I could be arguing against a strawman.
I am not an expert on infant formulas, but I think that if someone could factory-produce a drink that updates your immune system (as breast milk does), that would have huge implications in medicine. Essentially, we could replace vaccination by drinking soylent.
There have been many randomized controlled experiments of breast milk vs formula. Every single one of them has shown no effect.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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