Microsoft does not allow advertising for supplements where the product may present significant health risks. This includes weight-loss, muscle-building, and unverified herbal products.
Ingredients on Microsoft's restricted list (DMAA, ephedra, kratom, SARMs), aggressive weight-loss claims, anabolic-style muscle products, or unproven nootropics. Code 8388 specifically targets supplements in Audience Ads where rules are tighter than Search.