Supplement guides
Supplement guides, page 9
Plain-English guides on labels, doses, real prices, free trials and refunds. Written to help you check a product, not to sell you one.
Guides on this page
How to check if a supplement trial really exists on ClinicalTrials.gov
A step-by-step way to verify a supplement trial in the registry: what to search, which fields to read and which red flags to watch.
ResearchHow to tell if a journal cited by a supplement is credible
Use the NLM Catalog, PubMed retraction labels and Retraction Watch to check whether the journal behind a supplement claim is credible.
ResearchHow the DoseAudit score works: four scores, one verdict
Evidence, price, refund and transparency: what each DoseAudit score measures, how the average sets the verdict, and what the check date means.
ResearchHidden, mismatch, underdosed: what our ingredient labels mean
What hidden, mismatch and underdosed mean in a review, with real label examples, the FDA blend rule and a checklist to read a label yourself.
EvidenceDo blood sugar supplements work? What the evidence says
What NCCIH says about berberine, chromium and cinnamon, and what the labels, doses and scores in our 31 blood sugar reviews reveal.
EvidenceWhich sleep supplements have evidence? What the research says
What NCCIH and PubMed say about melatonin, magnesium and L-theanine, and how four sleep offers score when their labels meet the research.
EvidenceDo joint supplements work? What the evidence says
Glucosamine, chondroitin, turmeric and collagen under NCCIH and PubMed review, plus how five real joint offers score when labels meet research.
EvidenceDo gut health supplements work? What the evidence says
Probiotics, prebiotic fiber and laxative herbs under NCCIH, AGA and NIDDK review, plus how five real gut offers score on their labels.
EvidenceDo weight loss supplements work? What reviews show
What Cochrane and other reviews found on green tea and chromium, the FDA's hidden-ingredient warning, and how five weight loss offers score.
EvidenceDo prostate supplements work? What the evidence says
What NCCIH, Cochrane and the CAMUS trial say about saw palmetto and beta-sitosterol, and how five prostate offers score on dose and evidence.
Guides are general information, not medical advice. Read how we review and our medical disclaimer.