Statutory Instruments
2026 No. 680
FOOD, ENGLAND
The Food Supplements Purity Criteria (Magnesium L-threonate monohydrate) (England) Regulations 2026
Made
22nd June 2026
Coming into force
13th August 2026
The Secretary of State makes these Regulations in exercise of the powers conferred by regulation 3 and in accordance with regulation 5(1) of the Nutrition (Amendment etc.) (EU Exit) Regulations 2019 (“the 2019 Regulations”)(1).
There has been open and transparent consultation in accordance with Article 9 of Regulation (EC) No 178/2002 of the European Parliament and of the Council of 28 January 2002 laying down the general principles and requirements of food law, establishing the European Food Safety Authority and laying down procedures in matters of food safety(2).
In accordance with regulation 6(3) of the 2019 Regulations, a draft of this instrument has been laid before Parliament and approved by a resolution of each House of Parliament.
Citation, commencement, extent and application
1.—(1) These Regulations may be cited as the Food Supplements Purity Criteria (Magnesium L-threonate monohydrate) (England) Regulations 2026 and come into force on 13th August 2026.
(2) These Regulations extend to England and Wales.
(3) These Regulations apply to England only.
Purity criteria for magnesium L-threonate monohydrate
2. The purity criteria for magnesium L-threonate monohydrate are set out in the Schedule to these Regulations.
Signed by authority of the Secretary of State for Health and Social Care
L.S.
Sharon Hodgson
Parliamentary Under-Secretary of State
Department of Health and Social Care
22nd June 2026
Regulation 2
Schedule PURITY CRITERIA FOR MAGNESIUM L-THREONATE MONOHYDRATE
| Synonym | Magnesium L-threonate |
| Definition | |
| Chemical name | Magnesium (2R,3S)-2,3,4-trihydroxybutanoate monohydrate |
| CAS number | 500304-76-7(3) |
| Chemical formula | C8H16MgO 11 |
| Molecular weight | 312.51 Da |
| Colour (solid) | White |
| Assay |
Magnesium: 7.2% to 8.3% L-threonate: 82% to 91% |
| Description | A water-soluble white powder which is manufactured via a chemical synthetic process. |
| Identification | |
| Solubility | Soluble in water at 1% concentration at 25℃ and that is clear in solution at 1% concentration. |
| pH USP(4) (1% in H₂O) | 5.8 to 7.0 |
| Purity | |
| Loss on drying | Not more than 5.0% (105℃/4 hours) |
| Oxalic acid/oxalate | Not more than 0.5% (as oxalic acid) |
| Arsenic | Not more than 1 ppm |
| Lead | Not more than 0.5 ppm |
| Cadmium | Not more than 0.2 ppm |
| Mercury | Not more than 0.1 ppm |
S.I. 2019/651, amended by S.I. 2026/412. There are other amending instruments but none are relevant. These powers are exercised by the Secretary of State who is the “appropriate authority” for regulations applying in relation to England, as defined in regulation 5(4)(a).
EUR 2002/178, to which there are other amending instruments but none are relevant.
This is a reference to the CAS Registry Number assigned to this preparation by the Chemical Abstracts Service. This is available at https://www.cas.org/cas-data/cas-registry
United States Pharmacopoeia (USP), published by the United States Pharmacopeial Convention in Rockville, Maryland, USA. General Chapter 791 pH of the USP was revised in 2014 by a Supplement to the USP, published on 1st December 2014 (ISBN number 1936424223). USP is a nonprofit scientific organisation that develops and disseminates public compendial quality standards for medicines and other articles. The USP is available at https://www.usp.org