Magnesium: authorised health claims in Great Britain

Compiled and maintained by the Wellgard Scientific Editorial Team · Official register version: 19 May 2026 · Page updated: 17 October 2026 · Sources checked on: 16 October 2026

Magnesium has ten authorised health claims on the Great Britain nutrition and health claims register, every one of them under Article 13(1) and authorised by Commission Regulation (EU) 432/2012. All ten may be used on any food, drink or food supplement that is at least a "source of" magnesium: 56.25 mg or more per 100 g of a food, 28.125 mg per 100 ml of a drink, or 56.25 mg or more in the daily dose of a supplement, each being 15% of the 375 mg nutrient reference value. "High in magnesium" needs twice the source level, 112.5 mg per 100 g. Eight further wordings for magnesium were assessed and not authorised; they are listed lower down with the register's reasons.

The ten wordings cover five areas. Energy and fatigue: normal energy-yielding metabolism and a reduction of tiredness and fatigue. Muscles and nerves: normal muscle function, normal functioning of the nervous system and normal psychological function. Electrolyte balance, a claim no other vitamin or mineral heading on the register carries. Structure: the maintenance of normal bones and of normal teeth. And two roles at cell level, normal protein synthesis and the process of cell division. The register names magnesium itself, not any particular salt or form: the condition is met by the amount of magnesium a food or a supplement provides, whichever permitted compound supplies it. Sleep, cramps and blood pressure are the questions readers most often bring to magnesium; the register has no authorised wording on sleep or cramp in either direction, and the blood pressure wordings that were submitted were assessed and not authorised, as the lower table shows.

This is Wellgard's reproduction and explanation of official data. It is not a government website, a product approval, or a substitute for assessing the applicable law and conditions of use. The GOV.UK register is the authoritative source.

This page draws together everything the register records under the heading Magnesium: the authorised wordings and their conditions of use, reproduced word for word, and the wordings that were assessed and refused. The same rows appear in their alphabetical place on the minerals page and the non-authorised page of the register; the glossary, the explanation of how the thresholds are worked out and the full introduction are on the index page. Northern Ireland follows the EU register under the Windsor Framework; this page covers England, Scotland and Wales. The paragraphs, the labels section and the lines beginning "In plain terms" are Wellgard's explanation; register text is confined to the tables.

At a glance

• Register heading: Magnesium, listed on the minerals page of the register.
• Status: Authorised for use in Great Britain.
• Authorised health claims: 10, all under Article 13(1), authorised by Commission Regulation (EU) 432/2012. All share the standard "source of" condition.
• Nutrient reference value: 375 mg (Regulation 1169/2011, Annex XIII).
• "Source of" magnesium: 56.25 mg per 100 g of a food, 28.125 mg per 100 ml of a drink, or 56.25 mg in the daily dose of a supplement (15% of the reference value).
• "High in": 112.5 mg per 100 g, 56.25 mg per 100 ml of a drink, or 30% of the reference value in a supplement's daily dose (twice the "source of" amount).
• Scientific opinions behind the authorised claims: EFSA Journal 2010;8(10):1807; EFSA Journal 2009;7(9):1216.
• Assessed, not authorised: eight wordings under this heading, listed below with the register's reason and on the non-authorised page.
• Register version: Department of Health and Social Care, Great Britain nutrition and health claims (NHC) register, release of 19 May 2026.

Authorised health claims for magnesium

Reading the table: register text in the four columns is reproduced exactly; the "In plain terms" lines and the paragraphs on this page are Wellgard's explanation. Terms such as "source of", "high in" and "nutrient reference value" are defined in the glossary on the index page.

What you will see on labels

What this means on labels: a compliant pack quotes a register wording, for example "Magnesium contributes to normal muscle function", or a close equivalent that keeps the same meaning for the shopper, such as "Magnesium supports normal muscle function". Phrases that go beyond the register for this heading include "beats tiredness" or "gives you energy", "builds strong bones", "prevents osteoporosis" or "stops tooth decay", "brain booster", "lifts mood" or "sharpens memory", and any reference to preventing or treating a disease. The claim belongs to Magnesium at the qualifying amount: a pack cannot transfer it to another ingredient or to the product as a whole, and the general rule that a claim is made about the product as sold still applies. Flexibility of wording is explained in the Department of Health and Social Care guidance.

The nutrition declaration on a supplement states the amount of magnesium in the daily dose and that amount as a percentage of the nutrient reference value, so the "source of" test can be read straight off the pack: 15% or more (56.25 mg) and the claims in the table may be used; 30% or more (112.5 mg) and the pack may also say "high in magnesium". For a food the figures are given per 100 g or per 100 ml, and the thresholds are 56.25 mg and 112.5 mg per 100 g (28.125 mg and 56.25 mg per 100 ml for a drink), or 15% of the reference value per portion where the pack holds a single portion. Where a product carries a magnesium claim alongside claims for other nutrients, each nutrient must meet its own threshold; the claim for one cannot be lent to another.

Nutrition claims: "source of" and "high in"

Health claims and nutrition claims are separate lists with separate conditions. The two nutrition claims that apply to magnesium are the general vitamin and mineral entries of the Annex to Regulation (EC) No 1924/2006, reproduced here as the register records them. The register's condition still refers to Directive 90/496/EEC; the significant amounts now sit in Annex XIII of Regulation (EU) No 1169/2011, which replaced it, and that is where the 375 mg reference value and the 15% rule come from. For magnesium: "source of" is 56.25 mg per 100 g (28.125 mg per 100 ml of a drink, 56.25 mg in a supplement's daily dose) and "high in" is 112.5 mg per 100 g (56.25 mg per 100 ml of a drink).

Not authorised for magnesium

The register records eight wordings under the Magnesium heading that were submitted, assessed and not authorised. A refused wording may not be used on a food, drink or food supplement sold in Great Britain, and nor may a wording likely to mean the same to the shopper; flexibility of wording applies to authorised claims only. A refusal is a judgement on a specific wording against a legal test on the evidence assessed at the time, not a finding about magnesium itself, and it is a different status from "on hold", which means never assessed. Each row links to its entry on the non-authorised page for headings M to P.

Headings that begin with the same word but are separate register entries, with their own assessed wordings, stay on the non-authorised pages: Magnesium hydroxide. Combination products whose heading lists magnesium among several ingredients are also listed under their own headings there.

Frequently asked questions

Is magnesium for sleep an authorised claim?

No wording on sleep appears on the register for magnesium, authorised or refused, so no sleep claim may be made on a food or supplement. The nearest authorised wordings are "Magnesium contributes to normal functioning of the nervous system", "normal psychological function" and "a reduction of tiredness and fatigue". The absence is a fact about the list of assessed wordings, not a judgement on magnesium.

Can a label say magnesium supports normal blood pressure?

No. Three blood pressure wordings for magnesium were assessed and not authorised, including "An adequate magnesium intake can support to maintain normal blood pressure" and "Regulates blood pressure." A refused wording may not be used, and nor may a wording likely to mean the same to the shopper.

Can magnesium claim to prevent cramps?

No. The authorised wording is "Magnesium contributes to normal muscle function". "Prevents cramps" or "stops night cramps" names a specific complaint and promises more than the assessed effect, so it is not an equivalent wording.

How much magnesium does a supplement need to carry a claim?

At least 56.25 mg of magnesium in the daily dose recommended on the label, which is 15% of the 375 mg nutrient reference value. A food needs 56.25 mg per 100 g, or 28.125 mg per 100 ml for a drink; "high in magnesium" needs 112.5 mg per 100 g. The amount counted is the magnesium itself, whichever compound supplies it.

Sources and related pages

• Department of Health and Social Care, Great Britain nutrition and health claims (NHC) register, release of 19 May 2026: the authoritative source for every register string on this page.
• Magnesium on the register's minerals page, with the other minerals in alphabetical order; the index page carries the introduction, the method for the thresholds and the glossary.
• Non-authorised claims, headings M to P: the refused wordings for magnesium in their alphabetical place.
• Commission Regulation (EU) No 432/2012, the list of permitted Article 13(1) claims; Regulation (EC) No 1924/2006, Annex (nutrition claims); Regulation (EU) No 1169/2011, Annex XIII (nutrient reference values and significant amounts); guidance on flexibility of wording.
• On Health Insiders: What Is Magnesium Good For? The Vitamins and Minerals Guide, which explains the evidence behind magnesium in plain terms.

How to cite this page: Wellgard Scientific Editorial Team. Magnesium: authorised health claims in Great Britain (reproduction of the DHSC register, version 19 May 2026). wellgard.co.uk/pages/gb-health-claims-magnesium, accessed [date you viewed the page]. Original: Department of Health and Social Care. Great Britain nutrition and health claims (NHC) register, updated 19 May 2026. https://www.gov.uk/government/publications/great-britain-nutrition-and-health-claims-nhc-register

Corrections

This page is updated whenever gov.uk releases a new version of the register, and the version line at the top says which release it reflects. If you find a wording or condition that differs from the register, or an entry that is missing, email support@wellgard.co.uk with the heading and the entry number and we will check it against the source file and correct the page.

Version history: 19 May 2026 release of the register, carried on this page from 17 October 2026.

Register text is Crown copyright, reproduced under the Open Government Licence v3.0. Wellgard's explanatory text, glossary and summaries are Wellgard's own. Published by Wellgard, a trading name of Bayagan Group Ltd.