Magnesium
Also known as: Magnesium oxide, Magnesium sulfate, Magnesium citrate, Mg, Elemental magnesium
Effective Dosage
250-360 mg elemental magnesium daily based on study doses
What the Science Says
Magnesium is an essential mineral involved in hundreds of bodily processes. Clinical trials in the provided data show it can reduce fasting blood glucose in older adults with low magnesium levels and pre-diabetes when taken at 360 mg/day for 4 months. It also improved depression scores when added to antidepressant therapy at 250 mg/day over 6 weeks, and in surgical settings, magnesium sulfate injected locally reduced postoperative pain and opioid use. Benefits appear most pronounced in people who are already deficient in magnesium.
What It Doesn't Do
Won't fix blood sugar across the board — benefits in the provided studies were limited to people who already had low magnesium levels. A single low-dose IV bolus during surgery showed no meaningful reduction in opioid use in a large real-world study. Not a standalone treatment for depression. No evidence from these studies that it prevents diabetes long-term or improves HbA1c or insulin resistance. Won't treat atrial fibrillation — ionized magnesium levels did not predict post-surgical AF in a 200-patient study.
Evidence-Based Benefits
Essential mineral. Supports muscle/nerve function, sleep, stress response. Many are deficient.
Strong EvidenceEffective at: 200-400mg daily
Source: NIH ODS
Absorption & Bioavailability
Unknown from provided studies — oral magnesium oxide at 360 mg/day corrected deficiency in older adults with hypomagnesemia, suggesting reasonable absorption in deficient individuals, but bioavailability across forms and populations is not directly compared in the provided data.
Red Flags to Watch For
- Benefits in glycemic and mood studies were specific to people with confirmed magnesium deficiency — supplementing without deficiency may offer little benefit
- A large retrospective study of 257,000+ surgical patients found a single IV magnesium bolus was associated with slightly increased (not decreased) opioid use, raising questions about routine use
- Most studies are small (20–75 participants) and short-term — long-term safety and efficacy data are limited in the provided evidence
- Magnesium sulfate used in surgical studies is injected or applied locally — oral supplements are a very different delivery method and results should not be assumed equivalent
- Several papers in this dataset are irrelevant to human supplementation (battery research, plant stress, snail anesthesia) — be cautious of brands citing 'magnesium research' without specifying the context
Products Containing Magnesium
See how Magnesium is used in these analyzed products:
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-04-06