Magnesium supplementation
mg/day elemental
A magnesium salt or solution that delivers a few hundred milligrams of elemental magnesium a day. Blood magnesium is a lab reading; this page is the assigned dose.
Trials use oxide, chloride, or another salt at a few hundred milligrams of elemental magnesium a day. Low serum magnesium is common in type 2 diabetes, which is why insulin and sleep trials keep picking the salt. A multivitamin that happens to contain some magnesium is not the same exposure.
Also called magnesium oxide, magnesium chloride, oral magnesium.
Connected relationships
Randomized trial · Contested
Magnesium supplementation→Depression
Higher Magnesium supplementation decreases Depression.
Tarleton 2017 found that 248 mg a day of elemental magnesium as chloride, versus no treatment, cut PHQ-9 scores by 6.0 points among 112 primary-care adults with mild-to-moderate depression in an open-label crossover (95% CI -7.9 to -4.2). Barragán-Rodríguez 2008 found a similar drop versus imipramine in 23 older adults with diabetes and low serum magnesium.
Randomized trial · Contested
Magnesium supplementation→Insulin resistance (HOMA-IR)
Higher Magnesium supplementation moves Insulin resistance (HOMA-IR) only in some conditions. Read the mechanism.
Drenthen 2024 found that 15 mmol a day of oral magnesium for six weeks did not change clamp insulin sensitivity versus placebo in 14 adults with insulin-treated type 2 diabetes (M value 4.6 versus 4.4). An intensive-care loading dose then moved HOMA in stress hyperglycemia (Heidary 2021).
Randomized trial · Contested
Magnesium supplementation→Sleep duration and regularity
Higher Magnesium supplementation increases Sleep duration and regularity.
Schuster 2025 found that 250 mg of magnesium bisglycinate a day for four weeks lowered the Insomnia Severity Index by 3.9 points versus 2.3 on placebo in 155 adults who reported poor sleep (P=0.049). Hausenblas 2024 saw better deep and REM scores on magnesium L-threonate versus placebo in 80 people.
Sources
- EK Tarleton et al. (2017). Role of magnesium supplementation in the treatment of depression: A randomized clinical trial.
- L Barragán-Rodríguez et al. (2009). Efficacy and safety of oral magnesium supplementation in the treatment of depression in the elderly with type 2 diabetes: a randomized, equivalent trial.
- LCA Drenthen et al. (2024). Oral magnesium supplementation does not affect insulin sensitivity in people with insulin-treated type 2 diabetes and a low serum magnesium: a randomised controlled trial.
- S Shahmoradi et al. (2024). The Effect of Magnesium Supplementation on Insulin Resistance and Metabolic Profiles in Women with Polycystic Ovary Syndrome: a Randomized Clinical Trial.
- M Sadeghian et al. (2020). Oral Magnesium Supplementation Improved Lipid Profile but Increased Insulin Resistance in Patients with Diabetic Nephropathy: a Double-Blind Randomized Controlled Clinical Trial.
- M Rodríguez-Morán et al. (2019). Oral Magnesium Supplementation and Metabolic Syndrome: A Randomized Double-Blind Placebo-Controlled Clinical Trial.
- Z Heidary et al. (2021). Effect of Magnesium Loading Dose on Insulin Resistance in Patients With Stress-Induced Hyperglycemia: A Randomized Clinical Trial.
- J Schuster et al. (2025). Magnesium Bisglycinate Supplementation in Healthy Adults Reporting Poor Sleep: A Randomized, Placebo-Controlled Trial.
- HA Hausenblas et al. (2025). Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: A randomized controlled trial.