Koudounas S, Bader DL, Voegeli D
It seems to me that medical claims or the absence of medical claims would be relevant to the first definition, but not to the second definition. Peptides used for body-building purposes, [for example], are a substance that may be used by human beings with a view to modifying a physiological function by exerting a metabolic action. An MHRA spokesperson pushed back on this interpretation, stating: Case law has established that products which have the effect of modifying physiological function while having no beneficial effect on human health do not meet the definition of a medicinal product. Michael Saul, partner at Cosmetic Surgery Solicitors, expressed serious concerns over what he described as a deliberately ambiguous space and a regulatory middle zone that has formed in relation to injectable peptides

Supplementing with topical GHK-Cu can help restore some of these lost protective functions by delivering copper ions directly to the scalp, where they serve as essential cofactors for enzymes involved in tissue repair and hair follicle maintenance
Cell 184 , 32223241 e3226 (2021)
Blumenthal SL, Ohnmeiss DD, Guyer RD, Zigler JE: Comparison of Re-Operations in Cervical Total Disc Replacement vs