About
An independent reference project. We do not sell supplements.
Supplement Library publishes plain-language entries on dietary supplement ingredients. Each page opens with a direct answer, then names the public sources that support the rest of the text.
How entries are compiled
Factual claims on a published page are traced to a page we fetched: NIH Office of Dietary Supplements fact sheets, NCCIH health pages, the ISSN creatine position stand, or PubChem property records. If a government monograph does not exist, the entry says so.
- Dosage units stay in the unit the cited source used.
- A form that a source does not name is not attributed to that source.
- Literature-strength chips describe the cited record. They are not advice.
Which sources are used
Entries are built from public, named sources in a settled order of preference: NIH Office of Dietary Supplements fact sheets first, then NCCIH health pages, then position stands from professional bodies such as the International Society of Sports Nutrition, then chemical property records from PubChem. Where none of those covers a question, the entry says the record is absent rather than reaching for a weaker source.
Every entry lists its sources in full — title, publisher, URL, and the date the page was retrieved — so a reader can open the same document we read. Each entry also shows how many sources it rests on and when it was last updated. An entry with one source says one source.
What the evidence grades mean
Each entry carries one or more literature-strength chips, and there are only two values. Strong means the cited sources present the point as settled and describe it consistently. Limited means the cited record is thin, mixed, or explicitly described by the source as insufficient. The grade describes the state of the published record on that narrow topic — not how well anything works, and not a recommendation.
Corrections and updates
Entries are corrected in place. When the text of an entry changes, its last-updated date changes with it, and that date is shown on the page and in the page's structured data. Cited sources are re-checked against the live document when an entry is revised; if a source has moved or been withdrawn, the entry changes rather than keeping a citation that no longer supports it.
Scope
The library covers what an ingredient is, the forms it is sold in, how amounts are reported in the sources, and the questions people most often ask about it. It does not cover what a given reader should take, and it does not compare brands or rank products. Entry pages carry no advertising, no product scores, and no affiliate links.
What this site does not claim
- There is no medical review board.
- No page carries a medical-review byline or an interview credit.
- Entries do not claim that an ingredient cures, treats, or prevents disease.