7 Questions to Ask Before Buying Any Supplement

Run every supplement through these seven questions and you will avoid the vast majority of bad purchases.

Key takeaways

  • Base the decision on your diet, lifestyle or test results — not influencer hype.
  • Look for doses near the Daily Value or within studied ranges — not mega-doses.
  • Insist on a named third-party seal (USP, NSF, Informed-Choice), not a vague “lab tested” claim.
  • If a product fails two or more of these questions, skip it.

Who this is for

Anyone about to spend money on a supplement who wants a quick reality check first.

  1. Do I actually need it? Base the decision on your diet, lifestyle or test results — not influencer hype.
  2. Is the dose sensible? Look for doses near the Daily Value or within studied ranges — not mega-doses.
  3. Is it third-party tested? A named seal (USP, NSF, Informed-Choice) on the label, not a vague “lab tested” claim.
  4. What is the exact form? Glycinate versus oxide, D3 versus D2 — the form changes absorption and effects.
  5. Could it interact with my medication or conditions? When in doubt, ask your pharmacist — this is what they are for.
  6. What is the real cost per day? Do the serving maths; the cheapest bottle is often the most expensive habit.
  7. What is the return policy? Reputable brands stand behind their products.

If a product fails two or more of these questions, skip it.

Your next step

Learn how to read a supplement label like a pro.

Related reading: our complete beginner’s guide to supplements.

Written by the Nourish & Glow editorial team · Published 21 September 2026 · Last reviewed 21 September 2026

General information only — not medical advice. If you have a health condition, take medication, or are pregnant or breastfeeding, speak to a qualified professional before using supplements.

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