Magnesium Forms for Sleep Compared
Magnesium is the second big topic in sleep threads. Supplements come in many forms that differ in how much magnesium they deliver and how they are absorbed.[NIH Office of Dietary Supplements] We score each form separately, plus comments that do not name a form.
| Supplement | Score | Owner comments | Unwanted effects |
|---|---|---|---|
| Magnesium glycinate | 4.0 | 1039 | 15% |
| Magnesium (form not stated) | 4.2 | 938 | 9% |
| Magnesium L-threonate (Magtein) | 3.4 | 104 | 24% |
| Magnesium taurate | 3.5 | 26 | 7% |
Unwanted effects = share of rated owner comments that describe grogginess, headaches, stomach upset, vivid dreams or another unwanted effect.
Glycinate
Glycinate is the form people in sleep communities mention most, often as the "gentle on the stomach" option. Evidence for magnesium and sleep is thin: a 2021 meta-analysis of trials in older adults rated it low quality.[PubMed]
L-threonate (Magtein)
A 2024 randomized trial, funded by the ingredient maker, compared magnesium L-threonate with placebo in adults with self-reported sleep problems.[PubMed] On Reddit it scores lower than glycinate, partly because it costs more per milligram and some owners report headaches or vivid dreams.
Taurate
Magnesium taurate combines magnesium with taurine; we found no human sleep trial of this form.[PubMed]
Safety
- The NIH upper limit for magnesium from supplements is 350 mg a day for adults unless a doctor advises more; high doses commonly cause diarrhea, and people with kidney disease are at higher risk of magnesium build-up.[NIH Office of Dietary Supplements]
- Magnesium can reduce absorption of some antibiotics and osteoporosis drugs; space doses apart.[NIH Office of Dietary Supplements]
Compare: glycinate vs threonate · glycinate vs taurate.
Still comparing? Browse every sleep supplement we track, sorted by Reddit owner score. Our sleep supplement shortlists group top-rated options by what people report. New to this? Start with how to choose a sleep supplement.