Identify what the milligram number describes
Magnesium glycinate compound mass and elemental magnesium mass differ. Use the magnesium amount listed in Supplement Facts to add a capsule, multi and any magnesium-containing medicine. Without that distinction, a large front-label number can either exaggerate or obscure the actual nutrient exposure. [1][2]
Know what the limit covers
ODS lists an adult upper limit of 350 mg daily from supplements and medications, excluding magnesium naturally in food. This is a population guidance limit, not a recommended dose or an exact toxicity boundary. Clinician-supervised treatment may differ, and impaired kidney function increases concern about accumulation. [1]
A combined-intake example
Imagine two products supply 200 mg and 150 mg elemental magnesium. Their total is 350 mg before any magnesium-containing medicine is added. Being at that number does not prove the regimen is needed or safe for every individual. Significant symptoms or a large dosing error require assessment, not an online threshold calculation alone. [1]
| Example | Interpretation |
|---|---|
| 200 mg plus 150 mg | 350 mg supplemental magnesium |
| Food magnesium | Excluded from this particular upper limit |
| Kidney impairment | Needs individualized safety assessment |
Sources for this article
- Magnesium - Health Professional Fact Sheet
Source consulted: 2026-09-20. This is a reference resource, not a claim that we conducted the studies or tested a product. - Questions and Answers on Dietary Supplements | FDA
Source consulted: 2026-09-20. This is a reference resource, not a claim that we conducted the studies or tested a product.