Affiliate disclosure
The short version
Some links to buy supplements are affiliate links. If you use one, the store pays us a small commission. Your price is identical to going to the store directly. Nothing about how a supplement is graded depends on any of this.
Which programs
Today there is one: iHerb. Brazilian marketplaces may be added later, and this page will be updated when they are. We do not run display ads, and we do not accept payment to feature, review or re-grade a product.
How the links work
Purchase links point to a /go/ address on our own domain, which forwards you to the store with our affiliate tag attached. Two reasons for that: you can tell from the link itself that it is a purchase link, and we can change or drop a program without editing hundreds of pages. Nothing is required of you — no account, no code, no extra step — and the price at checkout is the same as if you had typed the store's address yourself.
The editorial rule
Grades come from published research, and they are set before any commercial question is asked. In practice that means:
- No brand pays for placement, and no brand can pay for a better grade.
- There is no sponsored content anywhere on the site.
- Whether an item is available to buy has no effect on its evidence grade.
- Supplements with limited evidence get no purchase button in ready-made AI answers. If the research is thin, we are not going to hand you a checkout link.
The same rules apply to the data we publish for machines. Our JSON API, llms.txt and MCP server read from the same source as the pages, so an agent gets the identical grade and the identical references — not a version tuned to sell more.
What the commissions pay for
Hosting, the reference verification pipeline and the periodic re-audits, and keeping the API and MCP server free to use. There is no paywall, no newsletter upsell, no user accounts and no tracking of individuals; analytics are aggregate only and no IP addresses are stored.
If you would rather not use them
That is fine, and it costs you nothing. Every analysis and every reference is readable without buying anything — note the name and the dose studied and buy wherever you like. How the grades themselves are decided is described in how we grade evidence.
This site is educational and does not give medical advice. Talk to a doctor before starting a supplement, especially if you take medication or are pregnant.