Related (scam supplements):
https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2807343Dietary supplement products were included in this case series if they were labeled as containing 1 of the following ingredients: R vomitoria, methylliberine, turkesterone, halostachine, or octopamine
40% did not contain a detectable amount of the labeled ingredient.
Among the other 60%, the detectable amount ranged from 0.02% to 334% of the labeled quantity.
Only 11% contained a quantity of the ingredient within 10% of the labeled quantity.12% had at least one FDA-prohibited ingredient
I think these are all "preworkout" / "fat burner" supps except Turk which is a "muscle-builder" / "test-booster" oh brother. If you look at the details in the table of the PDF, the
R Vomitoria, Turkesterone, and Halostachine supps at most had about 3% of the claimed amount of the thing, and many of them had literally none of it.