Hat tip to Sabine over at RP fans for this:
Sabine said:How much of a concern is fluoride in showering/bath water?"
Ray Peat said:"I don't think it's a problem. The soaps and shampoos people use are worse problems. Just washing the skin with pure soap alters the skin's endocrine function for days. and doing it every day is an "endocrine disrupter," even if there are no toxic additives in the soap."