The “sleepy girl mocktail” is just what it sounds like—a fizzy cherry concoction meant to lull you to sleep. This homemade tipple has taken over TikTok (and Sleepytime tea’s spot on many nightstands). The question of whether it actually works remains up for scientific debate, however. Many sleep experts argue that any benefits people may experience are probably from a placebo effect.
This drink is no “miracle drug,” says Thomas Kilkenny, director of the Institute of Sleep Medicine at Staten Island University Hospital. Although the mixture’s tart cherry juice can contain a trace of naturally occurring melatonin, Kilkenny says its inclusion probably has more to do with taste than sleep. The recipe also typically calls for sparkling water, which provides nothing beyond a pleasant fizz. But the mocktail’s star ingredient—and the likely source for any true improvement in sleep quality—is a common essential mineral: magnesium.
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Social media health influencers have recently brought magnesium back into the spotlight with supplements in the form of capsules, powdered “mood-boosting” drinks, sleep-aid gummies and now sleep mocktails. And while TikTok has carried a range of dubious health advice, there is scientific merit to upping your magnesium levels. The nutrient, in appropriate amounts, is vital to human health—from energy production to bone strength to blood pressure regulation.
How does magnesium help the body?
If there were a jack-of-all-trades mineral, many researchers would give the honor to magnesium. It’s involved in more than 300 enzyme reactions in the body, according to the National Institutes of Health.
One of magnesium’s most important roles is to relax muscles. It vies for the same binding sites on muscle cells as calcium, the molecule that signals muscles to contact. When magnesium outcompetes calcium, it triggers a cellular chain reaction that promotes muscle relaxation instead. In people with healthy magnesium levels, muscle cells at rest contain approximately 10,000 times more magnesium than calcium. People with a magnesium deficiency tend to have a harder time loosening muscles, which may lead to cramps and spasms.
Magnesium is also vital in the brain, where it helps neurons talk to one another by relaying chemical messages. Additionally, because the brain is constantly active, magnesium helps prevent nerve cells from becoming overstimulated. It serves a similar purpose when the body feels overly anxious. Brain cells involved in emotional processing fire rapidly, triggering the adrenal glands in the kidneys to release the stress hormone cortisol. Magnesium calms the brain by increasing the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), which acts as “the brakes of the brain,” explains Michael Breus, a clinical psychologist at the sleep wellness company Sleep Doctor. This slows down nerve signaling, giving the brain a temporary break from panic mode. Though magnesium can temporarily calm the brain, supplements should not be used as a replacement for professional care or approved medications—more research is needed to fully understand how effective magnesium may be for anxiety treatments. People with clinically diagnosed anxiety should consult medical professionals for appropriate treatment options.
How does magnesium help with sleep?
Magnesium’s functions in the body are key to its effects on sleep. Muscle stiffness—whether from anxious thoughts or a long, stressful day at work—can make it harder to settle in and doze off. Magnesium may help to relax these stressed-out muscles, and increased GABA activity also puts your body in a calm state, which can help stabilize mood and anxiety.
Additionally, there’s growing evidence that magnesium may reduce some types of pain. The mineral dulls sensory neurons that signal the brain when there is an injury somewhere in the body and trigger the sensation of pain. “If you don’t sleep particularly well because of [certain kinds of] pain, magnesium can be pretty helpful,” Breus says.
There’s currently no research studying magnesium’s effect on individual stages of sleep, but Kilkenny hypothesizes that someone taking a magnesium supplement may get an extra few minutes of sleep per night, increasing the total time at rest. This, in turn, could possibly allow for more deep and restorative sleep. Not all magnesium supplements are created equal, however.
At your local drugstore, you’re likely to find several options. Magnesium glycinate and magnesium citrate are the active ingredients in most sleep aids. Between the two, Rifkin recommends taking a magnesium glycinate supplement to help fall asleep faster because the gut tends to absorb it well. While magnesium citrate does induce a calming effect, it’s also a laxative and can irritate the stomach or cause diarrhea.
If you decide to try using a supplement—or a sleepy girl mocktail—for sleep, Kilkenny recommends taking it 30 to 60 minutes before bed to allow the magnesium’s effects to kick in. And while scooping a tablespoon of magnesium into a cup of cherry juice and sparkling water won’t solve all your problems, especially if other underlying issues may be contributing to poor sleep, experts say the magnesium dosage in the drink is safe. “There’s no reason not to try it,” Kilkenny says. “You might feel a little benefit, but don’t expect a miracle treatment.”
How much magnesium do people need?
The human body can’t produce magnesium, which means people need to consume enough to meet the recommended amounts: between 300 and 420 milligrams per day for adults. Supplements are a convenient source, although Claire Rifkin, a registered dietitian nutritionist at Claire Rifkin Nutrition, advises that a person should not take more than 350 milligrams of magnesium supplement per day. Consuming more than that increases the risk of diarrhea, abdominal cramps and nausea.
The preferred method of magnesium intake is through diet, Rifkin and Breus say. Many foods, such as black beans, bananas and salmon, are rich in this mineral. Rifkin says regularly eating leafy greens can nourish your body with a lot of other essential vitamins and minerals as well. “A lot of Americans are not eating plant-based foods,” she notes, “so they’re not eating the foods high in magnesium to begin with.”
Breus also says a significant number of people aren’t actually meeting dietary requirements. Studies have reported that about 10 to 30 percent of populations in developed countries are magnesium deficient—and experts say the real percentages may be much higher because low-magnesium diets are so common and there have been inconsistent measurements of magnesium intake in studies. Magnesium deficiency has been associated with an array of health problems including chronic insomnia, depression and heart disease, Kilkenny says.
Being more conscious about your magnesium intake could be key to your general health, as well as your sleep. As Breus puts it, “Magnesium is one of the most important minerals you could have.”