The Buzz: Magnesium

Up-close view of toasted pepitas in a dark gray bowl.

What’s the buzz?
Could magnesium be the magical (natural) sleep aid that will give us more restful nights? 

What does the science say?
You may have heard of — or even tried — the old advice to drink a glass of warm milk to help you go to sleep. The remedy might actually have some value, but it is not milk itself that promotes sleep. More likely, the drowsy feeling you may get is due to the magnesium content of milk. Research shows a possible link between magnesium and sleep, and that a deficiency could leave you tossing and turning. 

Magnesium appears to work in several ways to help you relax and promote sleep. First, it activates chemicals in the body that help calm nerves and reduce anxiety-inducing thoughts. Magnesium can help interrupt those signals and alleviate stress. Studies have shown that raising magnesium levels may improve stress levels and symptoms of stress in individuals with low serum magnesium and high levels of stress. 

Melatonin, the chemical that controls our sleep-wake cycle, is also correlated with magnesium levels. When magnesium is low, the body produces less melatonin, leading to restlessness and difficulty falling asleep. Melatonin itself has long been used by health-conscious consumers as a natural sleep remedy, but magnesium may offer a natural boost in melatonin production, too. In one study, older adults with insomnia who took 250mg of elemental magnesium had improved sleep quality and increased melatonin levels. It didn’t take long for supplement companies to catch on to this research; you’ll notice many natural sleep aids on the shelves at stores now have a combination of magnesium and melatonin to promote a better night’s sleep.  

Finally, magnesium may promote sleep by binding with receptors in the brain called GABA-receptors. Prescription sleep-aids also target GABA-receptors, so magnesium may act in a similar manner to induce sleep. But all of these theorized effects are predicated on being in a state of magnesium deficiency, which statistically speaking happens in about 2 percent of the population. 

What’s the takeaway?
Before you start taking magnesium supplements, as always, check with your physician, and keep in mind that the upper limit for magnesium supplements is 350mg per day for adults. Any more than that can have a laxative effect (whoopsy!). Supplements may also interfere with the absorption of other medications. In addition, although you have probably seen a variety of topical magnesium-containing creams and sprays on shelves that claim to promote a deeper night’s sleep, know that research is still underway to determine its effectiveness. How much magnesium can pass through our skin, which is the defense system to keep substances from entering our body, is still unknown and is key to determining necessary concentrations for effectiveness.   

Instead, consider increasing your magnesium intake naturally through food. Magnesium-rich foods include nuts and seeds, beans and legumes, some fruits such as tart cherries, pomegranates, and grapes, leafy greens, whole grains, and dairy. And since these foods contain other important nutrients, you can sleep even better knowing you’re improving your overall health, too.