How We Review Products
The short version
We compare supplements on what their labels state, not on how they feel to take. Our reviews are documentary: they read the supplement facts panel carefully, convert the figures into something comparable, and tell you where a product sits against others in the same category. We have not swallowed the contents and we do not pretend otherwise.
What we assess
- Active ingredient and form. Not just “magnesium” but which compound — glycinate, citrate, oxide — because the form changes what the milligram figure means.
- Amount per serving. Read against the serving size, which is frequently two or three units rather than one. A front-label figure that describes three capsules is not comparable to one that describes a single softgel.
- Elemental versus compound weight. Where a label states the weight of the whole compound rather than the mineral inside it, we say so. The difference can be several times over.
- Servings per container. The figure that determines what a product actually costs, as opposed to what it appears to cost.
- Format and serving burden. How many units a day, and in what form.
- Disclosure quality. Whether amounts are broken out per ingredient or hidden inside a proprietary blend. Where they are hidden, no dose comparison is possible, and we say that plainly rather than filling the gap.
- Stated third-party testing. Where a manufacturer states USP, NSF, Informed Sport or an equivalent, we record it as a claim the manufacturer makes. We have not verified it ourselves.
Where our data comes from
Product specifications come from the Amazon listing and the manufacturer’s own published materials. Where the two disagree, we prefer the manufacturer. Where neither states a value, the field reads “Not stated”.
What a review will never say
Our reviews do not claim a product treats, prevents or cures anything. They do not describe how a product made anyone feel, because nobody here has taken it. They do not compare a product against a health outcome. If you read something on this site that sounds like a health claim about a specific product, it is an error — please report it.
How products are chosen
Categories are populated from what is actually available on Amazon.com in that category, not from a shortlist of brands we have relationships with. Products are not removed for being unimpressive; a poorly disclosed label is useful information.
See also: our editorial policy and affiliate disclosure.