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Supplements

magnesium decreases skeletal muscle cramps

In plain terms: Does magnesium stop muscle cramps?

Leans against Supplements 🔬 Includes disconfirming

Part of: 🧪 magnesium

RefutedContestedStrong support
consensus score -0.55

Probably not—the best evidence (a Cochrane review) finds little to no benefit for the common night-time/idiopathic leg cramps.

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: All trials, pooled (Meta-analysis)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

1 support 2 contradict 0 tested null 0 mixed · 3 sources, 3 independent groups

What the evidence shows

Despite heavy marketing, the best evidence is **unsupportive** for idiopathic/nocturnal cramps in general/older adults: the Cochrane review found magnesium unlikely to provide clinically meaningful benefit. Some individual RCTs of specific formulations (e.g. magnesium oxide monohydrate) report benefit, keeping it from outright refuted, but the consensus leans against. measured_by:: [[skeletal musc

The evidence (3)

SourceGradeStanceQualityFinding
Roffe et al.
2002 · Med Sci Monit
RCT contradicts moderate Double-blind crossover RCT (chronic persistent leg cramps, non-pregnant): Mg citrate NOT significantly better than placebo.
Barna et al.
2021 · Nutr J
RCT supports moderate Multicenter double-blind RCT of magnesium oxide monohydrate (enhanced cellular absorption) for nocturnal leg cramps: reduced cramp burden vs placebo.
Garrison et al.
2020 · Cochrane Database Syst Rev
meta-analysis contradicts high Cochrane review (update): magnesium unlikely to provide clinically meaningful reduction in idiopathic/older-adult muscle cramps; efficacy for cramps remains unproven.

Disagree, or know a study we missed?

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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.