NutrimatchHow we rank supplements
Every recommendation on Nutrimatch is driven by the same thing: the quality of the clinical evidence behind it. Here is exactly how that works.
Where the data comes from
Our evidence database is built on research reviewed by Examine.com, an independent organisation that analyses human clinical trials on supplements and nutrition. Examine.com accepts no funding from supplement companies, manufacturers, or retailers — their grading reflects the published science only.
We use Examine.com as our source because it is the most rigorous, consistently updated, and genuinely independent supplement evidence database available. For each supplement–outcome pair they have reviewed, they assign an evidence grade based on the quality and consistency of human trials.
What the evidence grades mean
Each grade reflects how strong, consistent, and reproducible the human trial evidence is for a specific supplement improving a specific health outcome.
| Grade | What it means |
|---|---|
| A | Strong evidence — Multiple well-designed human trials with consistent results showing a meaningful effect. |
| B | Good evidence — Fewer studies, some inconsistency, or a more modest effect — but a clear signal in the data. |
| C | Some evidence — Limited, early-stage, or inconsistent research. Some signal exists but confidence is lower. |
| D | Weak evidence — Very limited research, highly inconsistent results, or an effect too small to be meaningful. |
| E | No evidence — Little to no credible evidence of an effect in human trials. |
Nutrimatch only shows grades A, B, and C. Supplements graded D or E are excluded entirely — we do not surface products where the evidence is too weak to justify a recommendation.
How the quiz maps to recommendations
The quiz works by narrowing down your health goals to specific clinical outcomes — the same outcome labels used in the Examine.com research database (for example, “sleep quality”, “anxiety”, or “power output”).
As you answer each question, your selections accumulate a set of outcome names. When you reach your results, we query every supplement that has been studied for those outcomes and has at least a grade C. Results are then ranked by evidence grade — grade A supplements appear before grade B, which appear before grade C.
Where the same supplement has been studied for multiple outcomes you selected, it appears once but shows all relevant outcomes in its card.
What does not influence rankings
Supplement rankings on Nutrimatch are determined entirely by evidence grade. The following factors have no effect on which supplements appear or in what order:
- Commission rates or commercial relationships with supplement brands
- Product price, margin, or retailer stock levels
- Popularity, sales volume, or user ratings
- Whether a product is available for purchase through our links
If a supplement has strong evidence but no available product link, it still appears in your results. If a supplement has a product link but weak evidence, it does not.
Availability
Nutrimatch covers supplements that are commercially available from major international retailers. Most are over-the-counter in all major markets. A small number — such as melatonin and DHEA — are available without a prescription in some countries but prescription-only in others. Where this applies, we note it on the supplement card. Your retailer will show what is available in your region.
We do not include controlled substances or compounds that are banned as supplements in major jurisdictions.
Limitations
Evidence grades reflect the research on specific supplement–outcome pairings, not any particular product or brand. The grade for “Magnesium → sleep quality” tells you that magnesium has strong evidence for improving sleep — it does not tell you whether a given product contains the right form, dose, or bioavailability.
Nutrimatch does not account for:
- Individual variation — the same supplement can affect people differently
- Drug interactions — some supplements interact with prescription medications
- Dose — typical doses are shown on each card, but optimal dosing is individual
- Underlying medical conditions that may make a supplement unsuitable
This is a research tool, not a medical service. We surface what the published evidence says; what you do with that information is your decision, and ideally one made in conversation with a healthcare professional.
Questions or corrections
If you believe a grade is wrong, a supplement is missing, or something does not look right, get in touch. We review feedback and update the database regularly.