mineral · for poor sleep quality
Magnesium Glycinate
Calms your nervous system so your body can wind down.
Say that in clinical terms
Magnesium enhances sleep quality by increasing slow-wave sleep duration, regulating the circadian clock via melatonin synthesis, and reducing nocturnal cortisol. It modulates GABA receptors promoting deeper, more restorative sleep stages.
How strong is the research?
2 papers read, 2 supporting.
Tested as: magnesium bisglycinate
Who was studied: One trial was in elderly Iranians with diagnosed insomnia. A 2025 glycinate trial in 155 adults aged 18 to 65 is the better match.
How much to take
daily, 30-60 min before bed
300–400 mg
Magnesium deficiency is strongly linked to poor sleep quality. Glycinate provides dual benefits from both magnesium and glycine.
Before you take it
- NIH ODS Tolerable Upper Intake Level (UL) for supplemental magnesium is 350 mg/day for adults; the principal adverse effect above the UL is osmotic diarrhea; hypermagnesemia is rare with intact renal function but possible with chronically elevated doses.
- Tetracycline antibiotics (e.g., doxycycline, demeclocycline) and quinolone antibiotics (e.g., ciprofloxacin, levofloxacin): take the antibiotic at least 2 hours BEFORE or 4-6 hours AFTER magnesium supplementation, per NIH ODS. Note: this timing requirement is asymmetric.
- Bisphosphonates (e.g., alendronate): magnesium reduces oral bisphosphonate absorption; take at least 2 hours apart, per NIH ODS.
- Antihypertensive medications (ACE inhibitors, ARBs, calcium channel blockers): magnesium may potentiate blood-pressure-lowering effects; blood pressure should be monitored when these are combined.
- Loop diuretics (furosemide) and thiazide diuretics increase renal magnesium excretion; potassium-sparing diuretics decrease magnesium excretion — both are clinically relevant interactions in common patient populations.
- Long-term proton pump inhibitor (PPI) use reduces intestinal magnesium absorption and causes hypomagnesemia independent of dietary intake.
- Renal insufficiency and chronic kidney disease: impaired renal magnesium excretion substantially increases hypermagnesemia risk; supplementation requires medical supervision.
- The antacid effect seen with magnesium hydroxide, carbonate, and oxide forms is form-specific and does not apply to magnesium glycinate at typical supplement doses.
- The cited source RCT administered 500 mg elemental magnesium per day (as magnesium oxide) — 43% above the NIH ODS supplemental UL of 350 mg/day; this dose should not be used to infer that recommended doses in the app are evidence-supported at equivalent levels
When to take it
Best taken: evening
What we make of it
The older trial used magnesium oxide. The glycinate trial found a small effect.
The detail
One citation is the same elderly-insomnia trial used elsewhere, which tested oxide rather than glycinate and was small. The 2025 trial of 155 people is the better match — it did test bisglycinate at 250 mg in the right population — but the effect on sleep quality was small.