Our method
How we research supplements
Every review follows the same steps, so you can see where each statement comes from and judge it for yourself.
Our steps
- Read the label. We start with the Supplement Facts panel: every ingredient, how much of each, and whether amounts are hidden in a “proprietary blend”. Where we can, we check the label record in the NIH Dietary Supplement Label Database.
- Compare the label with the sales page. If the sales page claims something the label doesn’t show, we point it out.
- Look up each ingredient. We search published research, starting with systematic reviews and meta-analyses, then individual clinical trials in people. We note how big and how long the studies were, and whether they used the same strain, dose and form as the product.
- Look for studies of the product itself. Research on single ingredients doesn’t show that a finished product works. We say clearly when no trial of the product has been published.
- Work out the real cost. We calculate the cost per day from the seller’s own prices, including shipping, and explain the guarantee and refund steps.
- Write it up in plain English. Every health statement links to a numbered source. Each review shows the date the research was last updated and the date prices were checked.
The sources we use
- Product labels, from the NIH Dietary Supplement Label Database and the seller.
- Published research found through PubMed and peer-reviewed journals.
- Government and professional health bodies, such as the National Institutes of Health and the American Dental Association.
- The seller’s own pages, for claims, prices and refund terms. We present these as the seller’s claims, not as facts.
- Public customer review pages, such as Trustpilot, to spot common complaints. We say when a review profile may not be representative.
How we rate evidence
Each ingredient gets one of three labels, based on research for the use the product is sold for:
| Label | What it means |
|---|---|
| Some evidence | Several clinical trials in people, with modest or mixed results. The studies are often small or short, or were done alongside other care. |
| Limited | Only a few small trials in people, or trials that used a different strain, dose or form than the product. |
| Very limited | Little or no research in people for this use. The ingredient may have been studied for something else, or only in the lab. |
These labels describe the research on each ingredient, not the product. Even “some evidence” for an ingredient doesn’t mean the product contains the amount that was studied.
What we don’t do (yet)
- We have not tested any product ourselves. Our reviews are research reviews. If we add hands-on testing later, it will appear in its own clearly labeled section on the review, with dates and details of what we did.
- No star ratings. We don’t give products a score, because we haven’t used them.
- No testimonials. We don’t publish customer stories or copy the seller’s testimonials.
- No disease claims. We describe what research suggests about ingredients. We don’t say a supplement will fix a health problem.
- No medical advice. Talk to your dentist or doctor about your own health. See our medical disclaimer.
Updates and corrections
Prices, labels and research change. Each review shows when we last checked. If you spot a mistake or something out of date, please tell us and we’ll look into it.
How we make money
We earn a commission when you buy through links on our reviews, at no extra cost to you. Read our affiliate disclosure to see how this works and how we handle it.