Earlier quoted context omitted.
Are they? Doesn't that have first amendment protection?
The US specialized in medical quackery for a hundred years, so there are direct restrictions on speech around claiming medical benefits. The free speech laws permit that, as IIRC societal welfare trumps your right to claim that (for example) mercury and cocaine soda will cure all ills. EDIT: Commenters are right, you have to try to profit to be prosecuted. If you give away poison and call it a cure, as long as you ha…
What isn't legal is selling a product and making false or unverified claims about medical benefits.