How do you know if a supplement is good quality?

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.

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.

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.

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.

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.