Magnesium Glycinate
Also known as Magnesium bisglycinate
Magnesium chelated to the amino acid glycine for better gut tolerance and absorption than inorganic salts; magnesium is a cofactor in over 300 enzyme reactions governing nerve transmission, muscle relaxation, and sleep.
Reported side effects:DiarrhoeaNauseaAbdominal cramping
Be careful if: pregnant, breastfeeding
Ask first if you take: other medicines
Suspect a side effect? Report it to the MHRA Yellow Card scheme ↗
What the research actually shows
We link to relevant studies and leave interpretation to you and your healthcare professional.
Safety and considerations
What sources report about side effects, who should be careful, and medicines to ask about first.
Reported side effects
| Reported effect | How often | Basis | Sources |
|---|---|---|---|
| Diarrhoea | unknown | Listed by NIH ODS fact sheets | Magnesium (NIH ODS fact sheet, Health Professional edition; retrieved via Internet Archive snapshot 2026-10-11)NHS: Vitamins and minerals — Others (Magnesium section) |
| Nausea | unknown | Listed by NIH ODS fact sheets | Magnesium (NIH ODS fact sheet, Health Professional edition; retrieved via Internet Archive snapshot 2026-10-11) |
| Abdominal cramping | unknown | Listed by NIH ODS fact sheets | Magnesium (NIH ODS fact sheet, Health Professional edition; retrieved via Internet Archive snapshot 2026-10-11) |
Serious effects reported
| Reported effect | How often | Basis | Sources |
|---|---|---|---|
| Magnesium toxicity from very high doses (low blood pressure, vomiting, difficulty breathing, irregular heartbeat, cardiac arrest; a few fatal hypermagnesaemia reports) | unknown | Listed by NIH ODS fact sheets | Magnesium (NIH ODS fact sheet, Health Professional edition; retrieved via Internet Archive snapshot 2026-10-11) |
Be careful if you…
| Applies to | What sources say | Sources |
|---|---|---|
| pregnant | No pregnancy-specific caution found in the sources checked (NIH ODS magnesium fact sheet; NHS 'Others' page); general adult limits apply. | Magnesium (NIH ODS fact sheet, Health Professional edition; retrieved via Internet Archive snapshot 2026-10-11)NHS: Vitamins and minerals — Others (Magnesium section) |
| breastfeeding | No breastfeeding-specific caution found in the sources checked (NIH ODS magnesium fact sheet; NHS 'Others' page); general adult limits apply. | Magnesium (NIH ODS fact sheet, Health Professional edition; retrieved via Internet Archive snapshot 2026-10-11)NHS: Vitamins and minerals — Others (Magnesium section) |
Medicines to ask about
| Severity | Medicine | Sources |
|---|---|---|
| listed | other medicines — NIH ODS: magnesium may interact with oral bisphosphonates, tetracyclines and quinolone antibiotics; diuretics and proton pump inhibitors can affect magnesium status. | Magnesium (NIH ODS fact sheet, Health Professional edition; retrieved via Internet Archive snapshot 2026-10-11) |
How much is too much
Suggested uses (unproven)
Where people report using it and what trials suggest
- Strong evidenceCorrection of magnesium deficiency
- Mixed evidenceSleep quality (modest, esp. low intake)
- Mixed evidenceAnxiety symptoms (mild)
- Weak evidenceMuscle cramps
Where the evidence is negative
Common claims the trials do not support
- No benefit for cramps in pregnancy RCTs vs placebo (large 2020 trial null).
- Depression trials are small and heterogeneous; not a substitute for treatment.
- Widespread 'everyone is deficient' claims are overstated for people with adequate diets.
Well-absorbed, gentle magnesium salt. Clear benefit for correcting deficiency; sleep/anxiety benefits are modest and mostly seen in people with low baseline intake.
Evidence grades reflect study quality and consistency, not marketing claims.
Ordered by strength of evidence, then result direction.
01The Role of Magnesium in Sleep Health: a Systematic Review of Available LiteratureArab A, et al. · Biological trace element research · 2023PMID 35184264 ↗02Oral magnesium supplementation for insomnia in older adults: a Systematic Review & Meta-AnalysisMah J, et al. · BMC complementary medicine and therapies · 2021PMID 33865376 ↗03Effects of magnesium and potassium supplementation on insomnia and sleep hormones in patients with diabetes mellitusKhalid S, et al. · Frontiers in endocrinology · 2024PMID 39534260 ↗04Effect of short-term magnesium supplementation on anxiety, depression and sleep quality in patients after open-heart surgerySaba S, et al. · Magnesium research · 2022PMID 36354243 ↗05Magnesium supplementation improves indicators of low magnesium status and inflammatory stress in adults older than 51 years with poor quality sleepNielsen FH, et al. · Magnesium research · 2010PMID 21199787 ↗06Dietary Protocols to Promote and Improve Restful Sleep: A Narrative ReviewConti F · Nutrition reviews · 2026PMID 40418260 ↗Show all 11 studies
Published research summaries are unavailable.
Why people look into Magnesium Glycinate — and what they report
Associated conditions and community-reported outcomes, wrapped together on one page. Aggregates appear only once enough reports arrive.
Where to get Magnesium Glycinate (UK)
How this compound is sold in the UK, and where our readers typically find it.
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