I’ve been researching CBD and the ability of marketing of it as a dietary supplement. Here is a statement I found on the FDA website as part of a warning letter to a company that was intending on marketing their CBD products as dietary supplements, dated 3/20/2017
"You should be aware that, based on available evidence, FDA has concluded that CBD products are excluded from the dietary supplement definition under section 201(ff)(3)(B)(ii) of the act [21 U.S.C. § 321(ff)(3)(B)(ii)]. Under that provision, if a substance (such as CBD) has been authorized for investigation as a new drug for which substantial clinical investigations have been instituted and for which the existence of such investigations has been made public, the products containing the substance are outside the definition of a dietary supplement. There is an exception if the substance was “marketed as” a dietary supplement or a conventional food before the new drug investigations were authorized; however based on available evidence, FDA has concluded that this is not the case for CBD.
The existence of substantial clinical investigations regarding CBD has been made public. For example, two such substantial clinical investigations include GW Pharmaceuticals’ investigations regarding Sativex and Epidiolex.1 FDA considers a substance to be “authorized for investigation as a new drug” if it is the subject of an Investigational New Drug application (IND) that has gone into effect. Under FDA’s regulations (21 CFR 312.2), unless a clinical investigation meets the limited criteria in that regulation, an IND is required for all clinical investigations of products that are subject to section 505 of the FD&C Act. FDA is not aware of any evidence that would call into question its current conclusion that CBD products are excluded from the dietary supplement definition under section 201(ff)(3)(B)(ii) of the FD&C Act, but you may present the agency with any evidence that has bearing on this issue".
https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm549298.htm