Label literacy
What is Elemental Magnesium?
The single number on a label that tells you what you're actually getting.
Short answer
Elemental magnesium is the amount of pure magnesium in a serving — separate from the weight of the compound it's bound to. It's the only number that lets you compare two products fairly.
Key comparison points
- 01Compound weight vs elemental weight
- 02Why 1,000mg on the front doesn't mean 1,000mg of magnesium
- 03Typical elemental amounts by form
- 04Where to find it on the label
- 05What to do if it isn't stated
- 06Comparing two labels side-by-side
Compound vs elemental
| Label headline | Often means elemental |
|---|---|
| 1,000mg magnesium bisglycinate | ~100–200mg elemental |
| 500mg magnesium citrate | ~80mg elemental |
| 400mg magnesium oxide | ~240mg elemental |
What Fair Shelf compares
- Whether elemental dose is clearly stated
- Elemental dose per serving
- Cost per elemental mg
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Related magnesium guides
Value pickBest Value Magnesium Glycinate in the UKForm explainerMagnesium Glycinate vs BisglycinatePricingWhy is Magnesium So Expensive?Informational only — not medical advice. Fair Shelf does not tell you to start, stop or switch supplements. Always check the label and speak to a qualified professional if unsure.