The supplement industry is largely unregulated in the US and UK. These are the official channels for reporting unsafe products — and the independent resources for checking what the evidence actually says before you spend money on something that may do nothing.
FDA MedWatch (US)
fda.gov/safety/medwatch-fda-safety-information-and-adverse-event-reporting-programWhat: Report adverse reactions or safety issues with supplements, food, and medical products to the US Food and Drug Administration.
When to use: If a supplement causes an unexpected reaction or you believe a product is unsafe or mislabelled.
MHRA — Yellow Card (UK)
yellowcard.mhra.gov.ukWhat: The UK's official system for reporting suspected side effects of medicines and supplements.
When to use: Any unexpected reaction to a supplement or medicine sold in the UK.
Examine.com
examine.comWhat: Independent, non-commercial database of supplement research. No ads, no affiliate links. Summarises the actual clinical evidence for hundreds of supplements.
When to use: Before buying any supplement — check what the research actually shows for your specific goal.
NHS — Vitamins and Supplements
nhs.uk/conditions/vitamins-and-mineralsWhat: NHS guidance on vitamins, minerals and supplements — what they do, recommended doses, and when they're necessary vs unnecessary.
When to use: For reliable, conservative guidance on common supplements from a trusted medical source.