Magnesium
Brief description
Magnesium is an important co-factor in more than 350 enzymes in the body, many of which play a crucial role in brain function. It may influence mood by regulating the concentrations of various chemical compounds in the brain(1).
Magnesium is required for energy production (ATP), glucose metabolism, DNA synthesis as well as nerve, bone, and cardiac functionality.
Dietary sources:
Dark leafy vegetables
Nuts & Seeds,
Whole grains & legumes
Meat & Fish
There are many forms of magnesium available as a supplement:
Magnesium citrate: highest bioavailability(2) and lowest risk of gastrointestinal side effects (especially potassium magnesium citrate)(3).
Mg chloride, gluconate and glycinate: good bioavailability(3).
Mg carbonate and Mg oxide: worst bioavailability / poor absorption.
Evidence base
Sleep: No compelling evidence (from multiple systematic reviews (SR)) suggests that magnesium supplementation improves sleep or insomnia(4-6).
Depression: Possible beneficial effect on depression with magnesium supplementation(7-9), with some studies suggesting a dose of <250mg/day(7).
Diabetes: Magnesium supplementation in type 2 diabetics was found to improve fasting blood glucose, HbA1c(10-12), and systolic & diastolic blood pressure (BP)(11). It may also improve LDL cholesterol levels (and possibly HDL and triglycerides) in T2DM(13, 14).
Migraine: Magnesium supplementation may reduce the frequency and intensity(12).
Recommended serving & duration.
For diabetics wishing to improve their cardiovascular risk – 200-300mg/day for up to 120 days seemed to be more effective(11). Other studies of type 2 diabetics found greater a reduction in BP with higher doses of magnesium (>300mg)(12).
Please refer to the ‘Recommended daily allowance’ of your respective country to determine a safe optimal dose.
Safety & tolerability(15)
Magnesium is generally safe and well tolerated. It is unlikely excessive dosages will be achieved from dietary sources alone.
Higher doses may result in the following:
Diarrhoea (higher in Mg Carbonate, chloride, gluconate and oxide).
Nausea and abdominal cramping
Very high doses >5000mg/day:
Magnesium toxicity and this can be fatal.
Can also be influenced by the following medication:
Bisphosphonates – Mg decreases absorption of drug.
Antibiotics – Can make less effective.
Diuretics – Can lower Mg levels.
Proton Pump inhibitors - Can lower Mg Levels.
References
Nazarinasab M, Behrouzian F, Abdi L, Sadegh Moghaddam AA, Sadeghi S. Investigating the effect of magnesium supplement in patients with major depressive disorder under selective serotonin reuptake inhibitor treatment. J Family Med Prim Care. 2022;11(12):7800-5.
Walker AF, Marakis G, Christie S, Byng M. Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study. Magnes Res. 2003;16(3):183-91.
Ranade VV, Somberg JC. Bioavailability and pharmacokinetics of magnesium after administration of magnesium salts to humans. Am J Ther. 2001;8(5):345-57.
Arab A, Rafie N, Amani R, Shirani F. The Role of Magnesium in Sleep Health: a Systematic Review of Available Literature. Biol Trace Elem Res. 2023;201(1):121-8.
Mah J, Pitre T. Oral magnesium supplementation for insomnia in older adults: a Systematic Review & Meta-Analysis. BMC Complement Med Ther. 2021;21(1):125.
Chan V, Lo K. Efficacy of dietary supplements on improving sleep quality: a systematic review and meta-analysis. Postgrad Med J. 2022;98(1158):285-93.
Moabedi M, Aliakbari M, Erfanian S, Milajerdi A. Magnesium supplementation beneficially affects depression in adults with depressive disorder: a systematic review and meta-analysis of randomized clinical trials. Front Psychiatry. 2023;14:1333261.
Botturi A, Ciappolino V, Delvecchio G, Boscutti A, Viscardi B, Brambilla P. The Role and the Effect of Magnesium in Mental Disorders: A Systematic Review. Nutrients. 2020;12(6).
Derom ML, Sayón-Orea C, Martínez-Ortega JM, Martínez-González MA. Magnesium and depression: a systematic review. Nutr Neurosci. 2013;16(5):191-206.
Asbaghi O, Moradi S, Kashkooli S, Zobeiri M, Nezamoleslami S, Hojjati Kermani MA, et al. The effects of oral magnesium supplementation on glycaemic control in patients with type 2 diabetes: a systematic review and dose-response meta-analysis of controlled clinical trials. Br J Nutr. 2022;128(12):2363-72.
Xu L, Li X, Wang X, Xu M. Effects of magnesium supplementation on improving hyperglycemia, hypercholesterolemia, and hypertension in type 2 diabetes: A pooled analysis of 24 randomized controlled trials. Front Nutr. 2022;9:1020327.
Asbaghi O, Hosseini R, Boozari B, Ghaedi E, Kashkooli S, Moradi S. The Effects of Magnesium Supplementation on Blood Pressure and Obesity Measure Among Type 2 Diabetes Patient: a Systematic Review and Meta-analysis of Randomized Controlled Trials. Biol Trace Elem Res. 2021;199(2):413-24.
Asbaghi O, Moradi S, Nezamoleslami S, Moosavian SP, Hojjati Kermani MA, Lazaridi AV, et al. The Effects of Magnesium Supplementation on Lipid Profile Among Type 2 Diabetes Patients: a Systematic Review and Meta-analysis of Randomized Controlled Trials. Biol Trace Elem Res. 2021;199(3):861-73.
Verma H, Garg R. Effect of magnesium supplementation on type 2 diabetes associated cardiovascular risk factors: a systematic review and meta-analysis. J Hum Nutr Diet. 2017;30(5):621-33.
(NIH) NIoH. Magnesium Dietary Factsheet Office of Dietary Supplements: National Institute of Health; [Available from: https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/.
