Magnesium Label Transparency Index: What Six Supplement Facts Panels Disclose

This page carries no affiliate links. It exists to record one thing: what six magnesium supplement labels actually disclose, measured the same way, so that anyone — a buyer, a writer, a journalist — can check a claim without taking my word for it.

Every supplement brand says its label is transparent. The word has no agreed meaning, so it costs nothing to use. What follows is an attempt to give it one: four checks that can be answered yes or no by reading a Supplement Facts panel and, where relevant, a public certification register.

The four checks

1. Does the ingredient line name the exact chelate? “Magnesium glycinate” is used two ways: as the name of a specific compound, and as a loose retail category. A panel that says bisglycinate or lysinate glycinate has told you which molecule you are buying. A panel that says only “glycinate” has not.

2. Can you separate elemental magnesium from compound weight? A fully reacted bisglycinate chelate is roughly 10% elemental magnesium by weight, so 200 mg of magnesium sits inside about 2,000 mg of chelate. Labels print one number or the other, and the larger one is the more flattering. A panel passes this check when the figure you need — elemental magnesium per serving — is unambiguous.

3. Is the raw material named? Naming the chelate supplier, such as Albion or its TRAACS line, ties the ingredient to a specific manufacturer with published research. It is not proof of quality, but it is a checkable fact rather than an adjective.

4. Is third-party verification confirmed in a public register? This is the check that separates most brands. A badge on a bottle is a graphic. An entry in a certifying body’s searchable database is a record. Only the second one can be looked up by a stranger.

The index

Brand	1. Exact chelate named	2. Elemental figure clear	3. Raw material named	4. Verified in a public register	Checks met
NOW Foods Magnesium Glycinate	Yes — “Magnesium Bisglycinate (Albion™)”	Yes — 200 mg elemental in two tablets, compound weight also given	Yes — Albion	Partial — no register entry, but published Eurofins assay data	3.5 / 4
Thorne Magnesium Bisglycinate	Yes — “Magnesium (bisglycinate)”	Yes — 200 mg per scoop	Not stated	Yes — NSF Certified for Sport, listed in NSF’s own database	3 / 4
Solaray Magnesium Glycinate 350 mg	Yes — “Magnesium Bisglycinate”	Yes — 350 mg in four capsules	Not stated	Partial — NSF-certified facility, which is not product or batch certification	2.5 / 4
Doctor’s Best High Absorption Magnesium	Yes, but a different compound — “Magnesium Lysinate Glycinate (Albion TRAACS)”	Yes — 200 mg elemental from 2,000 mg of chelate	Yes — Albion TRAACS	No — two of four badges under “Certifications” are graphics the company made itself	3 / 4
Pure Encapsulations Magnesium (Glycinate)	No — says “magnesium glycinate”, never bisglycinate	Yes — 120 mg elemental per capsule	Not stated	Not stated on the panel	1 / 4
Qunol Magnesium Glycinate 300 mg	No — “chelated magnesium glycinate”, a category term	Yes — 300 mg presented as elemental across retailers	Not stated	No	1 / 4

Three things the table shows

Only half the brands name the molecule. Of the six, three — NOW Foods, Thorne and Solaray — put a specific chelate on the ingredient line. Pure Encapsulations and Qunol use “glycinate” as a category. Doctor’s Best names its chelate precisely, but it is a different one: magnesium lysinate glycinate, bound to lysine as well as glycine, and the retail listing title drops the word.

Price and transparency are not related. The cheapest product per 100 mg in this set is Doctor’s Best. The most expensive is not the most disclosed. Solaray, among the cheapest true bisglycinates, names its chelate explicitly while Pure Encapsulations, at several times the price per milligram, does not.

Check 4 is where almost everyone fails. Only one brand in this set — Thorne — has a certification a stranger can look up in the certifying body’s own register. “Third-party tested” appears on far more labels than that. The phrase is not regulated and usually names no third party.

Methodology

Each row is drawn from a full review on this site, linked at the foot of this page. For each product I read the Supplement Facts panel as the manufacturer and major retailers publish it, then checked any certification claim against the certifying body’s public database rather than against the badge on the packaging.

• What counts as a pass on check 1: the ingredient line names a specific chelate. “Magnesium glycinate” alone is a fail, because the same words are used for the compound and for the category.
• What counts as a pass on check 2: the elemental magnesium per serving can be read off the panel without inference.
• What counts as a pass on check 4: an entry located in a certifying body’s searchable register. A logo, a self-issued graphic, or the unqualified phrase “third-party tested” does not pass.
• Half marks are given where a brand meets the spirit of a check through a weaker instrument: published assay data instead of a register entry, or facility certification instead of product certification.

Limits of this index. It measures disclosure, not quality. A product can disclose everything and still be poor value, and a product can disclose little and still contain exactly what it says. Formulations and labels change between batches; every row records what was printed at the time of reading. No product here was supplied by a brand, and no brand saw this page before publication.

How to run these checks yourself

The whole index can be reproduced on any magnesium product in a few minutes, and the method works on other supplement categories without modification.

1. Turn the bottle around and read the ingredient line, not the front label. The front is marketing copy; the panel is the regulated statement.
2. Find the elemental magnesium figure. If the label gives only a large number with no elemental line, apply the 10% rule: a fully reacted bisglycinate is roughly 10% magnesium by weight. The arithmetic is set out here.
3. Look for a supplier name on the ingredient line.
4. Take any certification claim to the certifier’s own website and search for the product. NSF, USP and Informed Sport all publish searchable registers. If the product is not in the register, the badge is decoration.

The six reviews behind this table

• NOW Foods Magnesium Glycinate — the brand that commissioned Eurofins testing of its competitors
• Thorne Magnesium Bisglycinate — the only NSF Certified for Sport entry in this set
• Solaray Magnesium Glycinate — facility certification, not product certification
• Doctor’s Best High Absorption Magnesium — lysinate glycinate, and the word the listing drops
• Pure Encapsulations Magnesium — the shortest ingredient list, the vaguest chelate name
• Qunol Magnesium Glycinate — where the absorption claim comes from

The full price comparison, including cost per 100 mg of elemental magnesium, is in the six-brand comparison.

Citing this index

You are free to quote, reproduce or adapt this table, including commercially, with attribution and a link to this page. If you are writing about supplement labelling and want a figure checked, or want to know how a product not listed here scores against the four checks, write to me — I will run it and add it.

Suggested citation: inareview. Magnesium Label Transparency Index: what six Supplement Facts panels actually disclose. inareview.com, 26 September 2026. https://inareview.com/magnesium-label-transparency-index/

Record of changes

• 26 September 2026 — first publication, six brands.

This index will be extended as further products are read. Corrections are welcome and will be recorded here rather than made silently.