Every page follows the same four steps.
1. Research
We start with primary and authoritative sources: government health agencies, clinical practice guidelines from major medical organizations, systematic reviews and meta-analyses, and individual randomized trials where they matter. We read the source, not a summary of it, and we record it in a central source registry so that the same study is cited the same way everywhere.
2. Review
An editor reads the finished draft against its sources. Anything that cannot be traced to a source is removed. Anything that overstates the evidence is rewritten. The editor also checks that the article answers the question a reader actually came with, that technical terms are explained, and that the reading level is appropriate.
3. Verify
For supplement products, the Supplement Research Editor checks the ingredient list, doses, price, guarantee and manufacturer claims against the product label and the seller's own website. If something cannot be confirmed, the page says "not independently verified". A product page is not published until the formula, manufacturer and guarantee have been confirmed.
4. Update
Every article shows its last review date. Pages are re-checked on a rolling schedule, sooner when guidelines or product formulas change. Readers can report an error through the contact page; see our corrections policy.
How we rate ingredient evidence
An ingredient does not have one evidence score. It has one for each use it is studied for, because the evidence for berberine and blood glucose is not the same as the evidence for berberine and weight. Each rating reflects human research only:
| Rating | Meaning |
|---|---|
| Strong | Consistent benefit across multiple well-designed randomized trials or a robust meta-analysis |
| Moderate | Benefit in several trials or a meta-analysis, with some limitations in size, duration or quality |
| Limited | A small number of trials, small samples, or short durations; results may not be reliable |
| Mixed | Trials disagree, or benefit appears in some outcomes but not others |
| Insufficient | Little or no human research; evidence is mainly laboratory or animal studies |
How we look at finished products
A product is not its ingredients. Even when individual ingredients have good evidence, the finished formula may use different doses, different forms, or a proprietary blend that hides the amounts. On every product page we state which of these applies:
- Clinical evidence exists for the finished product — rare, and we link the study.
- Evidence exists for individual ingredients only — the common case. We say which ingredients, at what doses, and whether the product's doses match.
- No relevant evidence found — we say so.
We separate manufacturer claims from established medical evidence, and we do not present one as the other.
Rating integrity
These are editorial assessments, not customer ratings. Affiliate relationships do not determine either score. We do not raise Evidence Ratings to improve conversion, and Product Fit Scores are calculated from the five stated practical factors. Scores may change only when the underlying evidence, formula, price, guarantee or other verified product information changes.
Evidence Rating and Product Fit Score
Supplement reviews use two separate scores because scientific evidence and practical product fit answer different questions.
| Score | What it measures |
|---|---|
| Evidence Rating | Strength and relevance of human evidence for the finished product and/or its named ingredients for the intended use. A practical product score never raises this evidence score. |
| Product Fit Score | An equal-weight average of five practical factors: formula completeness, ease of use, guarantee and buying terms, price/value, and category relevance. |
How the Product Fit Score is calculated
| Factor | What we assess | Weight |
|---|---|---|
| Formula completeness | Whether the ingredients, amounts and usable label information are sufficiently disclosed to understand what is being purchased. | 20% |
| Ease of use | How straightforward the format and seller-stated serving directions are, including penalties for conflicting product formats or unclear directions. | 20% |
| Guarantee & buying terms | Refund window, clarity of conditions, payment/subscription terms and other buying protections we can verify. | 20% |
| Price / value | Price in relation to formula disclosure, dosing, comparable options and what the buyer can verify. | 20% |
| Category relevance | Whether the named formula is logically aligned with the supplement category and intended use. This is a fit measure, not proof of effectiveness. | 20% |
Important: a product can have a relatively good Product Fit Score and still have a low Evidence Rating. Conversely, an ingredient may have meaningful research while a finished product scores poorly on transparency, value or buying terms.