Expert Answer

How do you know if a supplement is good quality?

Supplement Quality quality third-party-testing safety
Based on statements in publicly available expert videos. Educational only, not medical advice. Ask a qualified clinician before changing a supplement, medication, treatment, or testing plan.

Quick Answer

Use five checks: independent testing for purity and potency; a recognized mark such as NSF, USP, ConsumerLab, Informed Sport, or IFOS; a batch Certificate of Analysis; the form and dose used in studies; and blood testing when it can set the dose. The experts teach criteria instead of naming one brand.

What the Panel Says

Andrew Huberman
Andrew Huberman Strongly Agrees

Prioritize brands third-party tested for purity, potency, and lack of contaminants, avoid unnecessary fillers and binders, and use blood testing to personalize your dose.

Mark Hyman
Mark Hyman Strongly Agrees

Vet products by reading the Certificate of Analysis and looking for independent testing to catch contaminants and fillers; look for NSF, USP, or ConsumerLab.

Rhonda Patrick
Rhonda Patrick Agrees

Match the form to the supplement - e.g. triglyceride-form omega-3 with an oxidation check via IFOS - and treat sourcing as the biggest safety risk.

Bryan Johnson
Bryan Johnson Agrees

Look for clinical doses, full ingredient transparency, and third-party testing (COAs) - the criteria he applies, though stated while contrasting his own product.

Detailed Answer

The experts don't agree on every supplement, but they converge on a remarkably consistent checklist for judging whether any given product is worth buying. Here it is, in the order they emphasize.

1. Start with independent testing

First: is it third-party tested? Huberman's rule is to prioritize brands that are third-party tested for purity, potency, and lack of contaminants, while avoiding products with unnecessary fillers or binders. Patrick calls sourcing the single biggest safety risk in the industry and tells you to rely on third-party tested brands.

This is the non-negotiable first filter because, without pre-market regulation, it's the only external check that the label is true.

2. Check the certification and batch

Second: does it carry a recognized certification? The marks the experts actually name are NSF/NSF International, USP, and ConsumerLab (Hyman), Informed Sport for batch/heavy-metal testing (reference material), and IFOS for fish oil (Patrick). Third: can you see a Certificate of Analysis?

Both Attia and Hyman push past the seal to the batch-level COA - the lab report that exposes contaminants and fillers in the specific lot you're buying.

3. Check the form and dose

Fourth: is it the right form at a real dose, without junk? This is where quality meets efficacy. Patrick specifies the triglyceride form of omega-3 with an oxidation check; Attia flags that creatine gummies degrade and to use NSF-certified monohydrate powder; Johnson looks for clinical doses and full ingredient transparency (his criteria, though he states them while contrasting his own product, so take the standard and not the brand).

Fifth and last: personalize the dose. Huberman's point is that the "right" amount varies widely between people, so blood testing is the best way to set your own dose rather than guessing from a label.

Use criteria, not a favorite brand

Put together, that's the whole game in an unregulated market: verify it's what it says it is (third-party tested, certified, COA available), make sure it's a useful form and dose without fillers, and calibrate the amount to your own body. Notably, none of the experts answer "how do I know it's good" by naming a brand - they teach the criteria, which is the point of this page.

Related Questions

What's the single most important quality signal?

Third-party testing. Every expert who discusses quality names it first - Huberman, Patrick, and Hyman all treat independent testing for purity and potency as the baseline filter.

Beyond the seal, what should I check?

The Certificate of Analysis (COA) for that batch, which reveals contaminants and fillers. Attia says to request one; Hyman vets products by reading them.

Does the form of the supplement matter?

Yes. Patrick specifies triglyceride-form omega-3 with an IFOS oxidation check, and Attia flags that creatine gummies degrade - so use NSF-certified monohydrate powder instead.

How do I know the dose is right for me?

Huberman recommends blood testing to personalize your dose, since individual needs vary widely and a label can't tell you what you specifically need.

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