Magnesium glycinate

Grades and forms of magnesium glycinate

Magnesium glycinate (magnesium bisglycinate) contains 14.1 % elemental magnesium on an anhydrous basis. To declare 100 mg of magnesium per serving you need about 709 mg of powder, before any overage. That low content per gram is the main trade-off against the other forms in the magnesium guide.

Manufacturers buy magnesium glycinate powder in bulk in two broad physical forms. Fine powder suits capsules and dry blends. Granular material suits direct compression. Commercial grades also differ in composition, and that changes the label arithmetic.

What decides the choice:

• Composition: fully reacted bisglycinate, or a buffered grade blended with magnesium oxide. Buffering raises magnesium content per gram.
• Water content: hydrated material contains less magnesium per gram than the anhydrous figure.
• Particle form: powder or granular, matched to the dosage format.
• Quality standard: food grade or a pharmacopoeia grade, as your customer specification requires.

The specification sheet and certificate of analysis state the assay, magnesium content, water content and particle size for each lot. SoleChem sends both with its quote. Name the grade you need in the quote form.

EU regulatory status

Directive 2002/46/EC sets which vitamin and mineral substances may be used in food supplements. Magnesium bisglycinate is listed among the magnesium sources in Annex II of the Directive. Check that the material you buy matches the listed substance and meets the purity criteria the Directive requires. The permitted-forms guide explains how Annex II works.

The label declares magnesium, not the salt, in milligrams, using the units in Annex I of the Directive. The other mandatory particulars are covered in the labelling guide.

The EU has not yet set harmonised maximum amounts of magnesium in food supplements. Member states apply their own national limits, and these differ. See maximum levels by EU country and confirm with the competent authority of each target market.

Any health claim on a finished product must come from the EU Register of nutrition and health claims under Regulation (EC) No 1924/2006. The health-claims guide explains how to use the Register.

Formulation notes

The arithmetic below uses the theoretical 14.1 % magnesium, anhydrous basis. The label claims are examples, not recommended amounts.

In production, replace 14.1 % with the magnesium content on the lot’s certificate of analysis. Add overage from your own stability data. The elemental content calculator runs the same calculation for any assay value.

Capsules. The powder mass per serving is high, so larger claims are usually split across several capsules. A buffered grade lowers fill weight but changes the declared composition. Fine powders may need a flow aid such as silicon dioxide. See ingredients for capsules.

Tablets. Tablet mass rises quickly with the claim. Granular grades are the usual starting point for direct compression; fine powder generally needs granulation. See ingredients for tablets.

Powders and drinks. Glycine itself tastes sweet, but taste and dissolution vary between grades. Run a bench trial in the finished matrix. See ingredients for powders and sports nutrition.

Store and handle the material as the specification sheet states, in closed containers protected from moisture.

How it compares to other forms

Values are theoretical, anhydrous basis.

Magnesium glycinate needs about four times the powder mass of magnesium oxide for the same claim. For a detailed side-by-side, see magnesium citrate vs magnesium glycinate.