Magnesium Oxide vs. Magnesium Glycinate
Among 6,062 on-market magnesium products with an identifiable primary form, 52.4% use Magnesium Oxide (3,177 products) and 9.5% use Magnesium Glycinate (573).
| Magnesium Oxide | Magnesium Glycinate | |
|---|---|---|
| Quality tier | Tier 3 | Unrated |
| Magnesium by weight | 60.3% | 14.1% |
| Share of market | 52.4% | 9.5% |
| On-market products | 3,177 | 573 |
| Median declared dose | 100 elemental mg middle half: 47.38–140 | 100 elemental mg middle half: 28.2–185 |
| Most common brands | DC, Wonder Laboratories, GNC Mega Men | Metagenics, Metabolic Maintenance, KAL |
Doses are declared per serving in elemental mg. “By weight” is the share of the ingredient that is the nutrient itself (e.g. elemental magnesium in a magnesium salt).
Why Magnesium Oxide is tier 3
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
Why Magnesium Glycinate is unrated
Marketed as a gentler, well-absorbed chelate; no glycinate-specific human bioavailability trial is cited (Walker 2003 tested a generic amino-acid chelate, not glycinate, and did not assess clinical symptoms), so no tier is assigned.
Source: none located for glycinate specifically; see Walker AF et al. 2003, Magnes Res 16(3):183-191, PMID 14596323 (generic amino-acid chelate)
Other magnesium comparisons
- Magnesium Oxide vs. Magnesium Citrate
- Magnesium Oxide vs. Magnesium Aspartate
- Magnesium Oxide vs. Magnesium Amino Acid Chelate
- Magnesium Citrate vs. Magnesium Glycinate
- Magnesium Citrate vs. Magnesium Aspartate
- Magnesium Citrate vs. Magnesium Amino Acid Chelate
- Magnesium Glycinate vs. Magnesium Aspartate
- Magnesium Glycinate vs. Magnesium Amino Acid Chelate
- Magnesium Aspartate vs. Magnesium Amino Acid Chelate