Melatonin Vs. Magnesium for Sleep: Which Is More Effective? Experts Explain

“Melatonin is a hormone that promotes sleep initiation and maintenance, naturally produced by the body,” explained Kenneth Lee, M.D., the medical director of the Sleep Disorders Center at UChicago Medicine. The brain’s release of melatonin is tied to the time of day, per the Mayo Clinic, increasing when it starts to get dark out and decreasing when the sun begins to rise. “Melatonin helps regulate your circadian rhythm by signaling to your body that it’s time to wind down and prepare for sleep,” said Stephanie Crabtree, M.S., R.D., a functionally minded dietitian based in Sarasota, FL.

The levels of melatonin that your body produces remain steady and stable from your late teens until around age 40, at which point they begin to decline as you get older, according to the Cleveland Clinic (which is why many studies have looked at the benefits of melatonin for older adults). “Overall, melatonin can be helpful in regulating your sleep cycle,” said Dr. Lee. “This can be especially helpful in things such as shift work disorder, jet lag, and what’s called circadian rhythm disorders. This is where your natural clock is not aligned with what your schedule needs to be.” For example, if you need to be at work at 5:00 a.m. but can’t fall asleep until 1:00 a.m. no matter how hard you try, melatonin may help. “Melatonin at very specific timing could help shift your sleep schedule so that you fall asleep earlier and therefore you can wake up earlier as well,” Dr. Lee explained.

A review published in Neuroscience & Biobehavioral Reviews backs this up, finding that melatonin helped people with neurodevelopmental and sleep disorders fall asleep faster and stay asleep for longer. “However, in terms of the use of melatonin as a sleep aid, i.e. to help you fall asleep faster after you take it, the results are very mixed,” said Dr. Lee. Research in Sleep Medicine Reviews that analyzed 24 randomized controlled trials studying melatonin for chronic insomnia found that it may be effective in some age groups and for certain types of insomnia, but not for others.

“There are inherent side effect risks with melatonin which should be taken into account,” said Dr. Lee. Per the Mayo Clinic, oral melatonin may cause headache, dizziness, or nausea, as well as some less common side effects like mild tremors, anxiety, and confusion. Melatonin may also alter the efficacy of a variety of prescription medications, including blood thinners, anticonvulsants, blood pressure drugs, central nervous system depressants, diabetes medications, contraceptives, immunosuppressants, and some others, so it’s super important to speak with your doctor before taking it.

Magnesium is an essential mineral that plays a role in hundreds of bodily processes, including some that impact your sleep, especially when you take magnesium glycinate. “Magnesium supports sleep by relaxing muscles, reducing nervous system excitability, regulating neurotransmitters, and lowering anxiety,” explained Crabtree. “It also plays a role in the production of your body’s own melatonin from the pineal gland, helping maintain a natural sleep-wake cycle.”

While magnesium’s impact on sleep is not as direct as melatonin’s, it may support the processes that help relax the body and prepare it for rest. Specifically, Dr. Lee explained that magnesium is thought to influence the regulation of the neurotransmitter gamma-aminobutyric acid (GABA), which slows down activity in your brain and produces a calming effect. A 2024 study published in Sleep Medicine: X found that supplementing with magnesium L-threonate may improve sleep quality, but the researchers used subjective questionnaires to come to these conclusions. “Generally speaking, there is no clear evidence as to whether magnesium helps with sleep substantially. But it may work in some people,” said Dr. Lee. “With my patients, I also have similar findings where some patients find it somewhat helpful, but others don’t find it to help very much at all.”

“Magnesium can have side effects such as nausea, diarrhea, stomach pain, and potentially more serious complications with high doses,” Dr. Lee said, though some of these side effects do vary based on the type of magnesium you are taking. According to the National Institutes of Health (NIH), magnesium can also interact with several medications, including osteoporosis drugs, antibiotics, diuretics, and proton pump inhibitors.

As far as the research goes, the jury is still out on the efficacy of both melatonin and magnesium as sleep aids. However, if you’ve gotten the OK from your healthcare provider to try one, the sleep problems you are facing could help you decide which to try first.

“Melatonin may be best for difficulty falling asleep, jet lag, or adjusting your sleep schedule. But it doesn’t necessarily improve the depth or restorative quality of sleep,” said Crabtree. “Magnesium may be more helpful for insomnia or restless sleep because it promotes relaxation and reduces nighttime tension or anxiety. Magnesium is my first choice since it can aid in getting deep, restorative sleep, and it has a strong safety profile for long-term use.”

If you’re thinking about taking a supplement to help improve your sleep, be sure to consider other solutions as well. Dr. Lee recommended trying some of the following strategies (in this order):

• Sleep hygiene and stimulus control: “These are basic tips that can help make the bed or sleep environment as optimized and inviting for sleep as possible while also reducing any sorts of ‘distractions’ away from sleep,” Dr. Lee said. He suggested only using your bed for sleep and intimacy, getting up if you haven’t fallen asleep within 30 minutes and returning to bed when you feel sleepier, avoiding exercise and eating within one to two hours of sleep, and setting aside “relaxation time” in the 30 minutes to an hour before sleep.
• Cognitive behavioral therapy for insomnia (CBT-I): “For more severe cases of insomnia, this is the most powerful tool that we have at our disposal,” said Dr. Lee. “I like to think of CBT-I as retraining your brain and body on how to sleep. This is oftentimes the main thing that I will focus on with my patients to improve their sleep.”
• Testing for sleep disorders: If the above solutions aren’t working, you may need to assess if there is a sleep disorder at play. “If there is snoring or you’ve been told you stop breathing, these could be signs of sleep apnea,” said Dr. Lee. “Furthermore, things such as leg kicks could be a sign of periodic limb movements, which have been related to things such as restless legs syndrome. A consultation with a sleep doctor may reveal these things and help with sleep in general.”

Dietary supplements are products intended to supplement the diet. They are not medicines and are not intended to treat, diagnose, mitigate, prevent, or cure diseases. Be cautious about taking dietary supplements if you are pregnant or nursing. Also, be careful about giving supplements to a child, unless recommended by their healthcare provider.