You may have heard the hype around magnesium as a potential sleep aid. Magnesium is one of the essential minerals that help bodily functioning, influencing over 300 chemical reactions in the body. according to Harvard Health. One of magnesium's roles, research has indicated, may be in the regulation of sleep. Limited studies have suggested that magnesium supplements might be helpful for better sleep — but working out what time to take them, and whether magnesium supplements are the right solution for your sleep problems, is more complex than it seems.
The main argument that magnesium can increase sleep quality comes from its interaction with a neurotransmitter called GABA. Sleep doctor Dr. Michael Breus explained in 2017, "Magnesium plays a role in supporting deep, restorative sleep by maintaining healthy levels of GABA, a neurotransmitter that promotes sleep." Magnesium, he added, "encourages relaxation as well as sleep. Low GABA levels in the body can make it difficult to relax." There are various studies to back up the link between GABA and magnesium, and we also know that magnesium levels play a role in regulating the body's internal clock, or 24-hour cycle of circadian rhythms.
However, there are a few limitations to the idea that magnesium operates like a typical sleep aid that you take before bed. For one thing, the studies that found that magnesium helped sleep had one particular study area: people over 50. "Currently, the only research showing that these supplements improve sleep has been done in older adults, so it's not clear how they affect other populations," wrote Healthline. Harvard Health also notes that in those studies, magnesium showed only "small benefits," adding: "With such limited evidence, it is difficult to strongly support regular use of magnesium for insomnia."
For another, magnesium supplements in these studies weren't administered like sleeping pills, just before bed. They were aimed at raising magnesium levels overall, and were spread throughout the day. One of the most-cited studies, a 2002 study on magnesium and sleep on the elderly, gave participants 500mg of magnesium each day, in the form of 250mg supplements to be taken twice a day, morning and night. The study took place over eight weeks, with the aim of building up the participants' magnesium levels overall.
Taking magnesium at a particular point in the day, in other words, doesn't seem to be tied to sleep quality — and the best study we have indicates that you should probably spread it out rather than taking it in one dose. However, more studies need to be done to show when magnesium supplements might be best taken for sleep efficacy.
Currently, medical advice says that if you don't have a magnesium deficiency, a one-shot supplement won't do you as much good as improving your diet. "If you'd like to try magnesium for sleep, start off by increasing your intake from whole foods," said Healthline. Half a cup of spinach contains 78mg of magnesium, while an ounce of pumpkin seeds contains 168mg. We absorb a lot of magnesium from our guts, so raising your dietary intake of magnesium over time is likely the best way to reap the potential sleep benefits of magnesium, rather than taking a supplement and hoping for the best.
Either way, it's worth talking to your doctor about your sleep issues, and discussing whether it's the result of a vitamin deficiency, or broader lifestyle issues. They can help you figure out what's at the root of your trouble sleeping, and the most appropriate treatment for it.