Magtein Magnesium L-Threonate

The material is traded as a single supplement grade, specified on assay of magnesium L-threonate together with a declared elemental magnesium figure, typically in the range of seven and a half to eight and a half percent. Some producers also report the L-threonic acid content and the optical rotation, since the L configuration distinguishes the intended material from racemic threonate.

Physical options are limited to particle size and flow. A standard milled powder is used for capsule filling, while a granulated grade with a slightly larger particle and lower surface area is offered where moisture pick up during blending is a problem. Because the salt is hygroscopic, drum liners are heat sealed and desiccant sachets are usual, and no coated or encapsulated version is normally offered.

In the United States magnesium L-threonate is marketed as a dietary ingredient, supported by new dietary ingredient notification and by safety studies submitted by the original developer, and finished supplements are produced under 21 CFR Part 111. It is not an approved food additive and is not affirmed as generally recognised as safe for general food fortification, so its use is restricted to supplement formats rather than conventional foods and beverages.

In the European Union the salt is not among the magnesium sources permitted for food supplements under the annex to Directive 2002/46/EC, and it has no novel food authorisation, so it is not legally saleable as a supplement ingredient in the EU. Status differs by market elsewhere, with several Asian and Middle Eastern jurisdictions treating it as a permitted supplement ingredient subject to registration. No Codex or JECFA specification monograph exists for the salt.