Magnesium malate
Summary
Magnesium malate has almost no human outcome data. The one small randomized trial, of a magnesium plus malic acid tablet in fibromyalgia, found no clear effect in its blinded phase, and a 2019 evidence review rated it as making little or no difference to pain (no effect). Absorption claims rest on rat studies.
Key facts
- Magnesium salt of malic acid; 15.5% elemental magnesium by weight[2]
- 300 mg/day magnesium with 1,200 mg malic acid in the blinded trial; up to 600 mg/day magnesium open-label[3]
- Adult RDA 310–420 mg/day magnesium from all sources; UL for supplemental magnesium 350 mg/day[1]
- Same as other magnesium supplements: bisphosphonates, some antibiotics; PPIs can lower magnesium[1]
- Diarrhea and stomach upset at high doses, as with any magnesium supplement[1]
- 1 graded human outcome on this page
- October 10, 2026
How it works
ProposedMagnesium is a cofactor in hundreds of enzyme reactions, including energy production. Malic acid is an intermediate in the cell's energy cycle, which is the rationale for pairing them in fatigue and fibromyalgia products. No human study shows that the malate partner adds anything beyond the magnesium.[1][3]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Fibromyalgia pain and tenderness | No effect | No effect | Crossover RCT · n = 24 · 1995 Adults with primary fibromyalgia Form: tablet of magnesium 50 mg with malic acid 200 mg · Dose: 3 tablets twice daily (300 mg magnesium, 1,200 mg malic acid per day) · Duration: 4 weeks per blinded course, then 6 months open-label No clear treatment effect in the blinded, fixed-dose phase. Pain scores fell in the open-label, higher-dose phase, which had no placebo control. | 8587088 (opens PubMed)Source [3] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Magnesium malate | 15.5%[2] | In rats, magnesium malate gave the highest serum area under the curve of five compounds tested; no human comparison in our sources.[5] | No form-specific human tolerance data in our sources.[1] | Fibromyalgia (one small trial) |
Compound weight → elemental magnesium
500 mg magnesium malate ≈ 78 mg elemental magnesium
Studied doses
Doses studied in human trials ranged from 300 mg/day of magnesium with 1,200 mg malic acid (blinded phase) to 600 mg/day of magnesium (open-label phase), for 4 weeks to 6 months. 600 mg exceeds the 350 mg/day supplement upper limit.[3][1]
Intake reference: Adult RDA 310–420 mg/day from all sources (by age and sex). Upper limit for supplemental magnesium: 350 mg/day for adults.[1] The upper limit covers supplements and medicines only, not magnesium in food. NIH ODS fact sheet (updated January 6, 2026).
Dose math: how much compound supplies that much magnesium
| Form (elemental %) | 300 mg magnesium300 mg/day: magnesium in the blinded fibromyalgia trial | 350 mg magnesium350 mg/day: adult upper limit from supplements (a ceiling, not a target) |
|---|---|---|
| Magnesium malate (15.5%) | ≈ 1,940 mg compound | ≈ 2,260 mg compound |
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
Medicines
Medicines that can lower levels
- Proton pump inhibitors (long-term)NIH fact sheetUse for more than a year can cause low magnesium, which supplements may not fully correct.[1]
Who should be careful
- Kidney problems
- The risk of magnesium toxicity rises with impaired kidney function, because the kidneys remove excess magnesium.[1]
- High doses
- The adult upper limit for supplemental magnesium is 350 mg/day; high doses often cause diarrhea, nausea and cramping.[1]
- Pregnancy and breastfeeding
- The 350 mg/day upper limit for supplemental magnesium still applies; no malate-specific data in our sources.[1]
- Medicines
- See interactions: antibiotic and bisphosphonate timing matters.[1]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
How to read the label
- Label dose vs clinical doseSupplement Facts list elemental magnesium. The blinded trial used 300 mg/day of magnesium plus 1,200 mg malic acid, so compare both numbers on the label.[3][1]
- Convert compound weight to magnesiumA front label saying "1,000 mg magnesium malate" means about 155 mg of magnesium at 15.5%.[2]
- Count every source against the upper limitThe 350 mg/day UL counts magnesium from all supplements and medicines combined, not food.[1]
Cost per studied dose, without the sales pitch
Compare any product you already have by the amount it delivers, not by capsule count or front-of-pack weight.
Cost per studied dose
Enter the price, servings and the amount per serving from your label.
Frequently asked questions
Is magnesium malate good for fibromyalgia?
The evidence says probably not. The only randomized trial found no clear effect in its blinded phase, and a 2019 evidence summary concluded it makes little or no difference to pain.[3][4]
Is magnesium malate better absorbed than other forms?
In rats it produced the highest serum levels of five compounds tested. There are no human head-to-head absorption data in our sources.[5]
How much magnesium is in magnesium malate?
About 15.5% by weight, so 1,000 mg of the compound contains roughly 155 mg of magnesium.[2]
Does magnesium malate help energy or fatigue?
No human trial in our sources has tested it for fatigue or energy. The idea comes from malic acid's role in cell energy metabolism.[1][3]
Is magnesium malate safe?
It follows the same limits as other magnesium supplements: 350 mg/day of supplemental magnesium for adults, with extra caution in kidney disease.[1]
Sources
- [1]Magnesium: Fact Sheet for Health Professionals (updated January 6, 2026). NIH Office of Dietary Supplements, 2026. fact-sheet
- [2]Magnesium malate (CID 164748): C4H4MgO5, MW 156.38. PubChem, NCBI, 2026. database
- [3]Treatment of fibromyalgia syndrome with Super Malic: a randomized, double blind, placebo controlled, crossover pilot study.. J Rheumatol, 1995. crossover-RCT
- [4]Magnesium and malic acid supplement for fibromyalgia.. Medwave, 2019. systematic-review
- [5]Timeline (Bioavailability) of Magnesium Compounds in Hours: Which Magnesium Compound Works Best?. Biol Trace Elem Res, 2019. animal-study
What changed
- First draft. Every PMID checked against NCBI E-utilities esummary (title and year taken from the record) and abstracts read for the cited rows.
- Adversarial review pass: claims re-checked against cited abstracts; the open-label phase is described as uncontrolled; absorption claims limited to the rat data. Page set indexable.