Magnesium for sleep and stress: Does it actually work?
Magnesium is everywhere right now. It’s recommended for sleep, anxiety, stress, muscle relaxation, and even brain health. But how much of that is actually supported by good evidence?
In this episode of Surfing Stress, I wanted to take a careful look at magnesium, because the science is much more interesting than either “magnesium fixes everything” or “it’s all hype.”
I’ll explain what magnesium actually does in the body, why getting enough of it matters, and what the clinical trials really tell us about sleep and stress.
We’ll look at a recent trial of magnesium bisglycinate that found a real, but small, improvement in insomnia, and no significant improvement in perceived stress. We’ll also talk about magnesium L-threonate and the claims around sleep and brain health, where the evidence is interesting but still limited.
I also want to help you make sense of all those different bottles on the supplement shelf. Citrate, oxide, glycinate, malate, L-threonate… do they really do all the different things the labels suggest? Not quite.
And there’s an important safety side to this conversation. Magnesium supplements aren’t appropriate for everyone, particularly when kidney function is reduced, and magnesium can interfere with the absorption of some medications. I’ll explain what you should know and when it makes sense to discuss supplementation with your physician or pharmacist.
My main message is a simple one: chronic stress is not a magnesium deficiency. Magnesium is an essential nutrient, and there is some evidence that supplementation may modestly improve sleep in some people. But that is very different from saying that magnesium treats chronic stress.
My goal with this episode is not to tell you whether you should or shouldn’t take magnesium. It’s to give you enough of the science to understand what we know, what we don’t know, and what questions are worth asking before you decide.
I’ve included links below to the scientific papers and sources I discuss in the episode, so you can look at the evidence for yourself.
Magnesium may be useful. It just doesn’t need to be magical to be useful.
Sleep
Mah J, Pitre T. Oral magnesium supplementation for insomnia in older adults: a systematic review and meta-analysis. BMC Complement Med Ther. 2021;21:125. https://pubmed.ncbi.nlm.nih.gov/33865376/
Schuster J, Cycelskij I, Lopresti AL, Hahn A. Magnesium bisglycinate supplementation in healthy adults reporting poor sleep: a randomized, placebo-controlled trial. Nat Sci Sleep. 2025;17. https://pmc.ncbi.nlm.nih.gov/articles/PMC12412596/
Hausenblas HA, et al. Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: a randomized controlled trial. Sleep Med X. 2024;8:100121 (corrigendum 2025). https://doi.org/10.1016/j.sleepx.2024.100121
Lopresti AL, Smith SJ. The effects of magnesium L-threonate (Magtein) on cognitive performance and sleep quality in adults: a randomised, double-blind, placebo-controlled trial. Front Nutr. 2026. https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2025.1729164/full
Anxiety, stress and mood
Boyle NB, Lawton C, Dye L. The effects of magnesium supplementation on subjective anxiety and stress: a systematic review. Nutrients. 2017;9(5):429. https://pubmed.ncbi.nlm.nih.gov/28445426/
Afzal S, et al. Examining the effects of supplemental magnesium on self-reported anxiety and sleep quality: a systematic review. Cureus. 2024. https://www.cureus.com/articles/237565
Moabedi M, et al. Magnesium supplementation beneficially affects depression in adults with depressive disorder: a systematic review and meta-analysis of RCTs. Front Psychiatry. 2023;14:1333261. https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2023.1333261/full
Forms & bioavailability
Firoz M, Graber M. Bioavailability of US commercial magnesium preparations. Magnes Res. 2001;14(4):257-262. [oxide vs chloride/lactate/aspartate] https://pubmed.ncbi.nlm.nih.gov/11794633/
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):183-191. [citrate vs oxide] https://pubmed.ncbi.nlm.nih.gov/14596323/
Slutsky I, et al. Enhancement of learning and memory by elevating brain magnesium. Neuron. 2010;65(2):165-177. [rats / L-threonate] https://pubmed.ncbi.nlm.nih.gov/20152124/
Abraham GE, Flechas JD. Management of Fibromyalgia: Rationale for the Use of Magnesium and Malic Acid. J Nutr Med. 1992;3:49-59. https://doi.org/10.3109/13590849208997961
Deficiency, safety & interactions
NIH Office of Dietary Supplements. Magnesium — Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
U.S. FDA. Drug Safety Communication: Low magnesium levels can be associated with long-term use of proton pump inhibitor drugs (PPIs). 2011. https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety-communication-low-magnesium-levels-can-be-associated-long-term-use-proton-pump
Educational information only, not medical advice and not a dosing guide. Talk to your own clinician before supplementing, especially with kidney disease or if you take medications.
