Magnesium
Of 14,666 on-market magnesium products in the January 2026 DSLD dump, the median declared dose is 60 elemental mg, and 48.4% list unspecified/undisclosed form as the primary form.
Form share
Of 11,755 products with an identifiable primary form, here is the share held by each form of Magnesium on the market today.
| Form | Quality tier | n | Share |
|---|---|---|---|
| unspecified/undisclosed form | Unrated | 5,693 | 48.4% |
| Magnesium Oxide | Tier 3 | 3,177 | 27.0% |
| Magnesium Citrate | Tier 1 | 1,533 | 13.0% |
| Magnesium Glycinate | Tier 1 | 573 | 4.9% |
| Magnesium Aspartate | Unrated | 500 | 4.3% |
| Magnesium Amino Acid Chelate | Tier 2 | 279 | 2.4% |
Form share over time
Entry-year breakdown of the top forms, 2012–2025.
Dose distribution
Deciles of declared dose per serving (elemental mg), among 11,240 products with a disclosed amount, against the RDA of 420 and UL of 350.
- 37.2% of products fall below the fairy-dust threshold (50 mg, 20% of the studied low dose).
- 1.9% of products don't disclose an amount because Magnesium is declared inside a proprietary blend.
By dosage form
By target group
Top brands
| Brand | Products |
|---|---|
| Douglas Laboratories | 362 |
| NutraBio | 195 |
| DC | 195 |
| Bluebonnet | 181 |
| Wonder Laboratories | 179 |
| Source Naturals | 171 |
| Pure Encapsulations | 136 |
| NOW | 133 |
| The Vitamin Shoppe | 131 |
| Life Extension | 123 |
| Trace Minerals Research | 118 |
| Metagenics | 118 |
| Centrum | 117 |
| Nature's Way | 117 |
| Syntrax | 112 |
| Emergen-C | 111 |
| Solgar | 98 |
| XYMOGEN | 95 |
| Vitamin World | 90 |
| Country Life | 89 |
| Nature Made | 87 |
| ProCaps Laboratories | 82 |
| Nutri-West | 81 |
| Higher Nature | 79 |
| Integrative Therapeutics | 78 |
Forms explained
Label discloses only "Magnesium" with no salt form.
Elemental fraction: 60.3% (MgO, anhydrous (no stable commercial hydrate))
Virtually insoluble in water, only ~43% soluble even under peak gastric acid.
Source: Lindberg JS et al. 1990, J Am Coll Nutr 9(1):48-55, PMID 2407766
Elemental fraction: 16.2% (Mg3(C6H5O7)2, anhydrous granular (standard supplement-grade form))
Far more soluble than oxide across physiological pH; produced the highest urinary/salivary Mg response of forms tested in a human RCT.
Source: Lindberg 1990, PMID 2407766; Walker AF et al. 2003, Magnesium Research 16(3):183-191, PMID 14596323
Elemental fraction: 8.4% (Mg(C4H6NO4)2, anhydrous bis-aspartate -- commercial hydration state unconfirmed, provisional)
No head-to-head human bioavailability study specific to this salt was found.
Source: uncertain -- needs review
Lower urinary/salivary Mg response than citrate in one RCT, though "amino acid chelate" is not a single defined compound.
Source: Walker AF et al. 2003, PMID 14596323
Elemental fraction: 14.1% (Mg(C2H4NO2)2, anhydrous bisglycinate)
Marketed and studied as a gentler, well-absorbed chelate; showed greater clinical symptom improvement than oxide in a comparative RCT.
Source: Walker AF et al. 2003, PMID 14596323
Reference values
- RDA (adult): 420 elemental mg — 400mg (men 19-30), 420mg (men 31+); 310mg (women 19-30), 320mg (women 31+)
- Tolerable Upper Intake Level (adult): 350 elemental mg — Supplemental magnesium only (excludes food/water Mg); based on GI-distress (diarrhea) threshold, IOM 1997 DRI
- Studied clinical dose range: 250–400 mg
- Walker AF et al. 2003, Magnesium Research 16(3):183-191, PMID 14596323 -- RCT (n=46) comparing bioavailability of four Mg salts; citrate produced significantly higher urinary/salivary Mg response than oxide or amino-acid chelate. High end corroborated by a 400mg/day MgO pilot RCT in supraventricular arrhythmia.