Written by Greg Arnold, DC, CSCS. Magnesium supplement significantly improved sleep quality by increasing the levels of sleep hormone melatonin and decreasing the stress hormone cortisol.

Insomnia is characterized by a number of sleep-related problems, including an inability to initiate or maintain sleep and early morning awakening due to an inability to resume sleeping. Insomnia often manifests as excessive daytime sleepiness, frequently resulting in functional impairment throughout the day (1). Insomnia is estimated to cost our healthcare system more than $60 billion per year, robbing each American of 11.3 days of work each year (2).

Statistics show the prevalence of insomnia to be as high as 40-50% of elderly people older than 60 years of age (3). This is of significant concern because memory weakness and increased reaction time caused by insomnia put the elderly at higher risk for falling, cognitive impairments (4), weak physical function (5), and a nearly 3 times higher risk of mortality (6). Finally, insomnia frequently results in decreased quality of life and general health and increased health costs, stress, and depression (7).

Now a new study (8) suggests that magnesium supplementation may be an affordable and effective way to help improve sleep quality. The study involved 43 subjects (21 men, 22 women) between the ages of 61 and 70 who were diagnosed with insomnia based on an Insomnia Severity Index evaluation (9). They were given either 500 mg of magnesium (administered as magnesium oxide tablets twice daily (each tablet containing 414 mg magnesium oxide as 250 mg elemental magnesium)) or placebo per day for 8 weeks. They also provided blood samples, completed the Insomnia Severity Index, physical activity and sleep questionnaires before and after the study.

Although no significant difference was seen in total sleep time between the two groups, numerous improvements in sleep factors were seen in the magnesium group. Specifically, those in the magnesium group had a 14.5% decrease in the Insomnia Severity Index (16.52 to 14.14) compared to a 3.1% decrease in the placebo group (16.27 to15.77, p < 0.001), a 15.4% decrease in the time needed to fall asleep (1.3 to 1.1 hours) compared to no change in the placebo group (1.4 hours, p = 0.04), and an 8.9% increase in sleep efficiency (0.67 to 0.73 hours) compared to no change in the placebo group (0.66 hours, p = 0.02).

When suggesting how magnesium elicits these improvements in sleep quality, the researchers suggested  the 17% increase in the sleep hormone melatonin (9.31 to 10.90 picograms/milliliter) in the magnesium group compared to a 15% decrease in the placebo group (9.55 to 8.12 pg/mL, p = 0.02) and a 11.3% decrease in the stress hormone  cortisol (23.05 to 20.46 micrograms/dL) in the magnesium group compared to a 2.9% increase in the placebo group (21.61 to 22.25 mcg/dL, p = 0.03) may have played a role in the results.

For the researchers, “Supplementation of magnesium appears to improve subjective and objective measures of insomnia in elderly people and may become a useful instrument in managing sleep disorders in the elderly, which could also be extended as a helpful aid to the general population.”

Source: Abbasi B, Kimiagar M, Sadeghniiat K, Shirazi MM, Hedayati M, Rashidkhani B. The effect of magnesium supplementation on primary insomnia in elderly: A double‑blind placebo‑controlled clinical trial. J Res Med Sci 2012;17:1161-9.  

© Journal of Research in Medical Sciences

Posted September 23, 2013.

Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY.  You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com


  1. “Insomnia” posted on the CDC website.
  2. “High Cost of Insomnia May Be A Wake-Up Call” – USA Today 9/1/2012.
  3. Ancoli‑Israel S. Insomnia in the elderly: A review for the primary care practitioner. Sleep 2000;23:S23‑30.
  4. Blackwell T, Yaffe K, Ancoli‑Israel S, Schneider JL, Cauley JA, Hillier TA, et al. Poor sleep is associated with impaired cognitive function in older women: The study of osteoporotic fractures. J Gerontol A Biol Sci Med Sci 2006;61:405‑10.
  5. Dam TT, Ewing S, Ancoli‑Israel S, Ensrud K, Redline S, Stone K. Association between sleep and physical function in older men: The osteoporotic fractures in men sleep study. J Am Geriatr Soc. 2008;56:1665‑73.
  6. Stone KL, Ewing SK, Ancoli‑Israel S, Ensrud KE, Redline S, Bauer DC, et al. Self‑reported sleep and nap habits and risk of mortality in a large cohort of older women. J Am Geriatr Soc 2009;57:604‑11.
  7. Barbar SI, Enright PL, Boyle P, Foley D, Sharp DS, Petrovitch H, et al. Sleep disturbances and their correlates in elderly Japanese American men residing in Hawaii. J Gerontol A Biol Sci Med Sci 2000;55:M406‑11.
  8. Abbasi B.  The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial.  J Res Med Sci 2012 Dec;17(12):1161-9.
  9. Bastien CH.  Validation of the Insomnia Severity Index as an outcome measure for insomnia research.  Sleep Med 2001 Jul;2(4):297-307