The Secret Ingredient to a Good Night's Sleep: Magnesium
Magnesium is having a moment right now. In fact, Nutritional Outlook, a publication for manufacturers of dietary supplements and health foods, reports that magnesium is the second most popular mineral on the market and is set to overtake calcium within the next three years. Though magnesium's benefits are widespread, two, in particular, have made it a health and wellness must-have in recent years: relaxation and sleep.
Consider this your guide to the sleep-inducing nutrient—from how it works to the best ways to up your intake.
What is magnesium?
“Magnesium is a mineral we get from our food—and ultimately from our soil—that the body uses in more than 300 different reactions," says Jerrica Sweetnich, functional medicine practitioner and clinical nurse specialist. “It's really essential for our bodies."
One of the most abundant minerals in your body, magnesium plays a role in everything from blood pressure and blood sugar regulation to nerve and muscle function.
The many benefits of magnesium
In addition to supporting healthy blood sugar, blood pressure, and nervous system and muscle function, magnesium also helps your body produce energy, build bones, synthesize DNA, and more.
Magnesium also aids in relaxation and sleep. “Magnesium has a relaxing effect on muscles," says Sweetnich. After a hard workout, magnesium helps the body physically relax.
The mineral's soothing effects don't end there: “Magnesium also supports the function of an enzyme called COMT, which breaks down dopamine, our 'reward' neurotransmitter," Sweetnich explains. “Though dopamine can help us feel good, an excess can actually contribute to anxiety—so if your COMT enzymes don't function properly because of a lack of magnesium, an overload of dopamine can contribute to anxiousness and even panic attacks."
As anyone who's dealt with the symptoms of anxiety knows, the wound-up sensation and rumination can make falling asleep at night incredibly difficult. According to a 2016 study out of Germany, though, supplementing with magnesium may help improve heart rate variability (HRV), an indicator of stress in the body, suggesting that magnesium can be used to treat mood and sleep issues.
Another way magnesium promotes better sleep: “It also interacts with the neurotransmitter GABA, which has a calming, relaxing effect," says Sweetnich. Ample GABA production is crucial for helping the body ease into sleep at night.
How much magnesium you need
The average adult female needs 320 milligrams of magnesium daily, while the average adult male needs 420 milligrams, according to the National Institutes of Health (NIH).
Surveys consistently report, though, that most Americans don't consume enough magnesium. Not to mention, many experts suggest that over-harvesting in the U.S. has depleted much of the magnesium in our soil, “so even if you eat lots of magnesium-rich foods, you may not be getting as much magnesium from them as you once did," says Sweetnich.
In addition, some people need even more magnesium than this recommended daily amount. “People who are highly active, for example, use magnesium to produce ATP (the chemical energy we use to power workouts), so they have a higher demand for the mineral," Sweetnich explains.
According to the NIH, older adults and people with digestive issues, who typically don't absorb magnesium well, also need more than the average person.
Eating your magnesium
In a perfect world, you'd meet your magnesium needs by eating a balanced, whole-food diet.
Some of the best sources of magnesium: nuts. One serving of almonds, for example, contains 80 milligrams of magnesium, while a serving of cashews contains 74.
Spinach (which provides an impressive 78 milligrams of magnesium per serving) and legumes (including peanuts, black beans, and soybeans) are also good sources of the mineral.
“Another magnesium source everyone loves is dark chocolate," says Sweetnich. “The issue here, particularly in relation to sleep, is that dark chocolate also contains some caffeine, which can cancel out the calming benefits of magnesium, especially when eaten at night."
In addition to incorporating a variety of magnesium-rich foods throughout the day, if you want a magnesium-filled snack to munch on after dinner, Sweetnich recommends nuts. In addition to containing lots of magnesium, nuts also contain a good amount of protein, which is easier for the body to metabolize at night, meaning digestion is less likely to mess with your slumber.
Supplementing with magnesium for sleep
If you (like many people) have trouble meeting your magnesium needs through food alone, a supplement can help you up your intake and get your sleep back on track.
“Most of my patients benefit from a magnesium supplement," Sweetnich says. The trick is finding the right type for you.
Though there are a few different kinds of magnesium supplements out there (the most common being magnesium citrate), there are two particular forms Sweetnich recommends for supporting sleep.
First: Magnesium bisglycinate. “This form can really help with that muscle relaxation, so I have a lot of people take it at night," Sweetnich says.
Second: Magnesium threonate. “This one is really helpful for those missing out on sleep or dealing with anxiety because it affects those GABA levels to really help calm the nervous system," she explains.
Generally, Sweetnich recommends a minimum of 400 milligrams of these types of magnesium per day—taken about an hour before bed. Always consult with your doctor before adding new supplements to your routine.
The bottom line: “Just make sure you're also practicing good sleep hygiene, like staying away from screens," she says. “You've got to give the magnesium the right environment to do its job."
What are other vitamins and minerals play a role in how well you're able to catch Z's? Here are other nutrient deficiencies that can mess with your sleep.