Magnesium for Sleep

Question: My 70-year-old mother struggles with insomnia. Will magnesium supplementation help her sleep better?

Answer: Good sleep is vital for health, and while insomnia has many causes and remedies, we will focus on your question about magnesium. Magnesium is a mineral the body needs for more than 300 processes, including nerve signaling, proper muscle control, and production of melatonin, the hormone critical for a good night’s sleep. During the past few years scientists have been studying magnesium to see if it can help people sleep better. Some studies show it helps, but taking too much without guidance can be harmful.

Magnesium affects sleep by helping control certain brain chemicals (e.g., GABA), which calm the nervous system and make the body relax. It also helps keep melatonin at healthy levels. People who don’t have enough magnesium in their bodies often struggle with poor sleep, waking up in the night, or with conditions such as restless leg syndrome.

Giving extra magnesium helps some people but not others. A study in 2012 tested giving magnesium to older adults who had insomnia. Those who took 500 milligrams of magnesium each day for eight weeks fell asleep faster, slept longer, spent more of their time in bed sleeping rather than being awake, and didn’t wake up earlier than they wanted as often as before.[1] A 2021 review of many studies showed that magnesium made a small but noticeable improvement in sleep quality, especially for older adults and people who had insomnia to begin with.[2] Still, scientists say more studies (and those of longer duration) are needed.

Taking extra magnesium seems most helpful for people who are low in it.

Taking extra magnesium seems most helpful for people who are low in it. This includes older adults, people with stomach or intestinal diseases such as Crohn’s or celiac disease, people with type 2 diabetes, and those who don’t eat enough magnesium-rich foods, such as leafy greens, nuts, and whole grains. For these people, fixing a deficiency can improve both sleep and overall health. Your mom may fall into one of these groups; her doctor will be able to tell better.

But be aware, taking too much without guidance can cause stomach upset, cramps, nausea, diarrhea, drug problems, or even serious illness. The safe upper limit for adults is 350 milligrams a day from supplements, unless a doctor says otherwise. For people with kidney problems, magnesium can build up to dangerous levels, causing low blood pressure, confusion, weak muscles, and even irregular heartbeats. Magnesium can also lower the effect of some medicines or cause side effects when taken with water pills (diuretics), antibiotics, and bone medicines (bisphosphonates).

Anyone considering using magnesium for sleep should consult a doctor first. The best and safest way to get magnesium is still through a God-given, healthy diet full of foods that naturally contain it, such as black beans, kidney beans, spinach, tofu, nuts, oats, brown rice, and quinoa. These foods not only are rich in magnesium but also support overall health.

[1] Behnood Abbasi, Masud Kimiagar, et al., “The Effect of Magnesium Supplementation on Primary Insomnia in the Elderly: A Double-blind Placebo-controlled Clinical Trial,” Journal of Research in Medical Sciences 17 (December 2012): 1161-1169. 

[2] J. Mah and T. Pitre, “Oral Magnesium Supplementation for Insomnia in Older Adults: A Systematic Review and Meta-Analysis,” BMC Complementary Medicine and Therapies 21 (2021): 125, https://doi.org/10.1186/s12906-021-03297-z.