This has to do with section DSHEA and section 343, particularly as it has to do with New Dietary Ingredients. In a nut shell, DSHEA said that anything produced

This has to do with section DSHEA and section 343, particularly as it has to do with New Dietary Ingredients. In a nut shell, DSHEA said that anything produced after 1993 but has been used as, or in, a dietary supplement prior to 1993 for it to be legal. If it's not, then it is considered a New Dietary Ingredient (NDI) and thus must submit an NDI notification to the FDA. This is to notify that the ingredient was not present as, or in, a dietary supplement prior to 1993. It's super tedious because it's been 25 years since DSHEA and the FDA has yet to produce a final guidance or rule on dietary NDI submissions.