Main Points

  • Magnesium is an essential mineral and electrolyte for health.
  • Magnesium supplementation may improve memory and learning ability, reduce stress, improve sleep quality, and increase attention span.
  • Magnesium acts as an electrolyte and cofactor for over 300 different enzymes.


    • Magnesium L-Threonate is the ideal form of magnesium for increasing brain magnesium.
    • To correct for deficiency, magnesium citrate, gluconate, or diglycinate should be used (~25% absorption by weight).
    • Magnesium oxide and magnesium chloride are poor choices and should be avoided (< 10% absorption rate).

      Other Sources

      • Green leafy vegetables, nuts and seeds, dark chocolate, avocado, fish.

          How to Take

          • 200 - 400 mg magnesium per day. Preferably with a meal or at bedtime.

              Natural Stacks Supplements Containing Magnesium


              Effects On Brain Health

              Magnesium plays a critical role in brain health by preserving neuronal function during periods of downtime. Deficiency can result in abnormal neuronal excitation (cells have more activation during periods when they are not intentionally activated), anxiety, and stress.

              Magnesium has been shown to increase NMDA transmission and signaling, a pathway in the brain that controls synaptic plasticity and memory function [1, 2, 3, 4].

              A study in aged rats showed that 50 mg/kg/day elemental magnesium was associated with increased spatial memory (short and long term), memory recall, and working memory (short term only) [2]. Another arm of the same study using young rats showed that enhanced learning effects ceased upon cessation of magnesium administration [2].

              In a recent double-blind, placebo-controlled human trial using magnesium threonate, researchers concluded that, "Overall cognition improved significantly at week 6 and maintained improvement at week 12". They also concluded that magnesium improved 'brain age' by 9 years based on "restored impaired executive function of the subjects" (age 50-70) [5].

              Additionally, neuroscientists from universities in Beijing, Texas, and Toronto found that increased serum magnesium in the brain enhanced synaptic plasticity, and improved learning and memory [6].

              Twelve scientists at MIT conducted a study on magnesium L-threonate and concluded that “an increase in brain magnesium enhances both short-term synaptic facilitation and long-term potentiation and improves learning and memory functions” [7].

              Lastly, increased brain magnesium levels may prevent or reverse cognitive deficits and synaptic loss [7].


              Effects On Stress and Mood

              Magnesium has been shown to improve mood during stressful conditions [8, 9, 10, 11].

              While there isn’t a good relationship between serum magnesium and depression, magnesium deficiency is associated with major depression in otherwise healthy individuals [12].

              One study showed that the removal of magnesium from the diet of rats resulted in anxiety and depressive-like symptoms [13].

              A review from 2010 concluded that increased rates of depression were correlated with dietary reduction of magnesium, and reported an inverse relationship between magnesium intake and depressive symptoms when controlling for both socioeconomic and lifestyle factors [14, 15].


              Effects On Hyperactivity

              There is some evidence suggesting that magnesium deficiency is related to hyperactivity. One study of 116 hyperactive children noted a magnesium deficiency of 95% (16).

              In another intervention of 50 hyperactive children there was a significant improvement in hyperactivity in response to 200 mg magnesium per day over a 6 month period [17].


              Effects On Sleep

              Magnesium supplementation confers sedative-like effects that can improve sleep quality.

              When a study sample of 12 healthy elderly subjects took an increasing dose of magnesium (from 346 to 738 mg), slow wave sleep quality was significantly increased [18].


              Effects On Testosterone

              Magnesium may have the potential to either increase or normalize testosterone levels, though the magnitude of effect is likely pretty small, existing in the range of several percentage points [19, 20].


              Side Effects

              Possibility of gastrointestinal upset in high doses or when taken on an upset stomach.


              1. Li, F., & Tsien, J. Z. (2009). Memory and the NMDA receptors. The New England journal of medicine, 361(3), 302.
              2. Slutsky, I., Abumaria, N., Wu, L. J., Huang, C., Zhang, L., Li, B., ... & Tonegawa, S. (2010). Enhancement of learning and memory by elevating brain magnesium. Neuron, 65(2), 165-177.
              3. Nakazawa, K., McHugh, T. J., Wilson, M. A., & Tonegawa, S. (2004). NMDA receptors, place cells and hippocampal spatial memory. Nature Reviews Neuroscience, 5(5), 361-372.
              4. Slutsky, I., Sadeghpour, S., Li, B., & Liu, G. (2004). Enhancement of synaptic plasticity through chronically reduced Ca 2+ flux during uncorrelated activity. Neuron, 44(5), 835-849.
              5. Liu, G., Weinger, J. G., Lu, Z. L., Xue, F., & Sadeghpour, S. (2016). Efficacy and safety of MMFS-01, a synapse density enhancer, for treating cognitive impairment in older adults: a randomized, double-blind, placebo-controlled trial. Journal of Alzheimer's Disease, 49(4), 971-990.
              6. Abumaria, N., Yin, B., Zhang, L., Li, X. Y., Chen, T., Descalzi, G., ... & Zhuo, M. (2011). Effects of elevation of brain magnesium on fear conditioning, fear extinction, and synaptic plasticity in the infralimbic prefrontal cortex and lateral amygdala. Journal of Neuroscience, 31(42), 14871-14881.
              7. Slutsky, I., Abumaria, N., Wu, L. J., Huang, C., Zhang, L., Li, B., ... & Tonegawa, S. (2010). Enhancement of learning and memory by elevating brain magnesium. Neuron, 65(2), 165-177.
              8. Poleszak, E., Wlaz, P., Kêdzierska, E., Nieoczym, D., Wyska, E., Szymura-Oleksiak, J., ... & Nowak, G. (2006). Immobility stress induces depression-like behavior in the forced swim test in mice: effect of magnesium and imipramine. Pharmacological reports, 58(5), 746.
              9. Poleszak, E., Wlaź, P., Kędzierska, E., Nieoczym, D., Wróbel, A., Fidecka, S., ... & Nowak, G. (2007). NMDA/glutamate mechanism of antidepressant-like action of magnesium in forced swim test in mice. Pharmacology Biochemistry and Behavior, 88(2), 158-164.
              10. Poleszak, E., Szewczyk, B., Kędzierska, E., Wlaź, P., Pilc, A., & Nowak, G. (2004). Antidepressant-and anxiolytic-like activity of magnesium in mice. Pharmacology Biochemistry and Behavior, 78(1), 7-12.
              11. Poleszak, E., Wlaz, P., Kêdzierska, E., Radziwon-Zaleska, M., Pilc, A., Fidecka, S., & Nowak, G. (2005). Effects of acute and chronic treatment with magnesium in the forced swim test in rats. Pharmacol Rep, 57(5), 654-658.
              12. Nechifor, M. (2009). Magnesium in major depression. Magnesium research, 22(3), 163-166.
              13. Spasov, A. A., Iezhitsa, I. N., Kharitonova, M. V., & Kravchenko, M. S. (2007). Depression-like and anxiety-related behaviour of rats fed with magnesium-deficient diet. Zhurnal vysshei nervnoi deiatelnosti imeni IP Pavlova, 58(4), 476-485.
              14. Eby, G. A., & Eby, K. L. (2010). Magnesium for treatment-resistant depression: a review and hypothesis. Medical hypotheses, 74(4), 649-660.
              15. Jacka, F. N., Overland, S., Stewart, R., Tell, G. S., Bjelland, I., & Mykletun, A. (2009). Association between magnesium intake and depression and anxiety in community-dwelling adults: the Hordaland Health Study. Australian and New Zealand Journal of Psychiatry, 43(1), 45-52.
              16. Kozielec, T., & Starobrat-Hermelin, B. (1997). Assessment of magnesium levels in children with attention deficit hyperactivity disorder (ADHD). Magnesium Research, 10(2), 143-148.
              17. Starobrat-Hermelin, B., & Kozielec, T. (1997). The effects of magnesium physiological supplementation on hyperactivity in children with attention deficit hyperactivity disorder (ADHD). Positive response to magnesium oral loading test. Magnesium research: official organ of the International Society for the Development of Research on Magnesium, 10(2), 149-156.
              18. Held, K., Antonijevic, I. A., Künzel, H., Uhr, M., Wetter, T. C., Golly, I. C., ... & Murck, H. (2002). Oral Mg2+ supplementation reverses age-related neuroendocrine and sleep EEG changes in humans. Pharmacopsychiatry, 35(04), 135-143.
              19. Cinar, V., Polat, Y., Baltaci, A. K., & Mogulkoc, R. (2011). Effects of magnesium supplementation on testosterone levels of athletes and sedentary subjects at rest and after exhaustion. Biological trace element research, 140(1), 18-23.
              20. Brilla, L. R., & Haley, T. F. (1992). Effect of magnesium supplementation on strength training in humans. Journal of the American College of Nutrition, 11(3), 326-329.