Elemental Magnesium Content in Magnesium Bisglycinate
375mg of magnesium bisglycinate contains approximately 50-75mg of elemental magnesium, representing roughly 13-20% of the total compound weight.
Understanding Magnesium Bisglycinate Composition
Magnesium bisglycinate is an organic chelated form where one magnesium ion is bound to two glycine molecules. The molecular weight breakdown determines elemental content:
- Molecular weight of magnesium: ~24 g/mol
- Molecular weight of glycine: ~75 g/mol each (×2 = 150 g/mol)
- Total molecular weight of magnesium bisglycinate: ~174 g/mol
This yields an elemental magnesium content of approximately 14% by weight (24/174), though commercial preparations may vary between 13-20% depending on buffering agents and manufacturing processes 1.
Practical Calculation for 375mg
Using the standard 14% elemental content:
- 375mg × 0.14 = 52.5mg elemental magnesium
- Range accounting for formulation variability: 48-75mg elemental magnesium
Clinical Context for Dosing
Recent clinical trials using magnesium bisglycinate provide practical reference points:
- A 2025 randomized controlled trial used 250mg elemental magnesium daily from magnesium bisglycinate, which would require approximately 1,785mg of the bisglycinate compound 2
- Your 375mg dose therefore provides roughly one-fifth to one-quarter of this therapeutic dose
Bioavailability Considerations
Magnesium bisglycinate demonstrates superior absorption compared to inorganic forms, making the lower elemental content less concerning 3, 1:
- Intestinal absorption typically ranges 35-50% for magnesium compounds 4
- Organic chelated forms like bisglycinate show significantly better bioavailability than magnesium oxide in head-to-head studies 5
- Bisglycinate specifically demonstrated better intestinal permeability in Caco-2 cell studies with maximum effect at 3 hours 1
Important Caveats
- Check the product label for manufacturer-specified elemental magnesium content, as buffered formulations may vary 2
- If the supplement lists "magnesium bisglycinate buffered chelate," the elemental content may be at the higher end (18-20%) due to additional magnesium from buffering agents 1
- Administering at night when intestinal transit is slowest maximizes absorption 3