Key Clinical Evidence
Meta-analyses and landmark trials — hard endpoints only
| Study / Meta-Analysis | N | Finding | Significance |
|---|---|---|---|
| Qu et al. (2013) — Meta-analysis | 532,979 | Each 100mg/day Mg increase → −7% all-cause mortality risk | P < 0.001 |
| Del Gobbo et al. (2013) — Meta-analysis | 313,041 | Highest vs. lowest dietary Mg → −22% CHD risk | P < 0.001 |
| Veronese et al. (2020) — Meta-analysis | 40,000+ | Higher Mg intake → −26% type 2 diabetes risk | P < 0.001 |
| Nielsen et al. (2010) — RCT | 100 | Mg supplementation improved sleep efficiency, REM sleep, and early morning awakening in older adults | P = 0.002 |
| Abbasi et al. (2012) — RCT | 46 | 500mg elemental Mg for 8 weeks → improved ISI, sleep time, sleep efficiency, melatonin, serum renin | P < 0.05 all endpoints |
| PREDIMED sub-study (2019) | 7,216 | Higher dietary Mg → −34% CV mortality in highest vs. lowest intake quartile | Prospective cohort |
Magnesium oxide (most common/cheapest) has only ~4% bioavailability. Glycinate chelate achieves 80%+ absorption. Malate is preferred for muscle fatigue. Threonate has superior CNS penetration and is used for cognitive protocols.
Mg²⁺ is required for all three steps of ATP synthesis in the mitochondrial inner membrane. Mg deficiency directly impairs cellular energy production — the root mechanism behind fatigue, muscle weakness, and cardiac dysfunction.
Mg regulates Ca²⁺ channels in cardiomyocytes (natural calcium antagonist), reduces arterial stiffness, lowers systolic BP by 2–4 mmHg in meta-analyses, and reduces arrhythmia risk via stabilization of the resting membrane potential.
Mg is a co-factor for insulin receptor tyrosine kinase. Deficiency causes insulin resistance independent of other metabolic factors. RCTs show supplementation reduces fasting glucose by 5–6 mg/dL in pre-diabetic individuals.
Dosing Protocol
By form — the form determines both the dose and the primary benefit
Evidence-Based Dosing by Form
⚠ Safety Considerations
Generally very safe — excess is excreted renally. Contraindicated in severe kidney disease (GFR <30). High doses can cause loose stools — the body's natural cutoff. Magnesium can reduce absorption of certain antibiotics (tetracyclines, fluoroquinolones) — space by 2 hours. Interacts with bisphosphonates — consult prescriber.
Best Products by Evidence
Ranked for elemental Mg content, chelation quality, and bioavailability certification
Thorne's TRAACS chelation process produces a true amino acid chelate that survives GI transit intact — significantly outperforming less tightly bound "bisglycinate" products from other brands.
Get on Fullscript ↗Uses the same TRAACS chelation technology as Thorne at roughly half the cost. Ideal for maintenance supplementation at 200–400mg/day.
Get on Fullscript ↗The only form shown to measurably increase cerebrospinal fluid Mg levels. Use alongside glycinate — not as a replacement — when targeting cognitive or sleep protocol goals.
Get on Fullscript ↗