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Two-thirds of all Americans don’t get adequate sleep, and only a small fraction of people feel truly rested, according to the Sleep Health Organization. This should sound an alarm, because sleep is perhaps the most important thing we can do for our health each day. Poor sleep quality is linked to a higher risk of obesity, heart disease, diabetes, memory problems, and anxiety.
At the root of many sleep issues is poor sleep hygiene — too much caffeine, too much screen time, too much evening light exposure, inadequate sunlight during the day, alcohol, and poor dietary habits. A lack of key nutrients can sit at the core of many of these problems, and one of the most common deficiencies tied to poor sleep is magnesium.
At least half of the population falls short on magnesium from diet alone, and the problem runs deeper than food choices. Our soil is increasingly depleted of magnesium, which means our food supply is too. Combine that with high intakes of processed food and medications that deplete the body’s magnesium stores, and it’s easy to see why nearly everyone benefits from supplementing.
This post covers the research on magnesium for sleep, the best forms to consider, and my personal review of Presleep Magnesium and other supplements on the market today.
This post is not medical advice. Review any new supplement with your healthcare provider before starting it.
Table of Contents
• People Don’t Get Enough Magnesium in Their Diets
• Magnesium-Rich Foods
• The Benefits of Magnesium for Sleep
• Magnesium Balances Neurotransmitters
• Magnesium Helps Make Melatonin
• Magnesium Helps Reduce Anxiety and Depression
• Magnesium Replaces Losses from Medications
• Magnesium Helps Reduce Muscle Cramping and Restless Legs
• Magnesium Helps Primary Insomnia
• Magnesium Helps Overall Health
• Magnesium Supplement for Sleep: My Review
• Magnesium Glycinate Benefits
• Magnesium Threonate Benefits for Sleep
• L-Theanine Benefits for Sleep
• Risks of Magnesium Supplements
Table of Contents
People Don’t Get Enough Magnesium in Their Diets
Putting it plainly, people aren’t eating enough magnesium, and this is almost universal. In a recent compilation study of over 3,900 young adults, average magnesium intake was 142 mg per 1,000 calories per day, with even the highest intake group averaging just 192 mg per 1,000 calories. That means even people with above-average intake often aren’t hitting the recommended daily intake (RDI).
For reference, the RDI for magnesium is 400–420 mg per day for men and 310–320 mg per day for women. Pregnancy and lactation raise these needs:
- Pregnancy: 350–360 mg per day
- Lactation: 310–360 mg per day
Interestingly, in that same large study, people eating the most magnesium tended to sleep better than those eating less — though it’s hard to fully tease out this pattern when so few people are getting enough of this mineral to begin with. Keep in mind the RDI was designed to prevent severe deficiency, not to optimize sleep. Many people may benefit from doses above the RDI for sleep support specifically, but always check with your healthcare provider first.
Magnesium-Rich Foods
Magnesium deficiency in plants has become an increasingly recognized issue as agricultural demands rise, and USDA data on the magnesium content of whole foods hasn’t been meaningfully updated in years — meaning the numbers below may actually overestimate real-world magnesium content. Still, it’s worth maximizing your intake through food where you can:
- Hulled pumpkin seeds, ¼ cup: 162 mg
- Almonds, ¼ cup: 96 mg
- Peanuts, ¼ cup: 65 mg
- Whey protein, ¼ cup: 64 mg
- Lima beans, ½ cup: 50 mg
- Baked potato, small: 90 mg
- Shredded wheat, ½ cup: 30 mg
- Dark chocolate, 1 ounce: 50 mg
- Oysters, 3 ounce: 49 mg
- Milk, 1 cup: 39 mg
- Mozzarella, 1 ounce: 36 mg
- Spinach, 2 cups raw: 48 mg
- Black beans, 1 cup: 120 mg
The Benefits of Magnesium for Sleep
Magnesium is required for over 600 reactions in the body, and over 300 enzymes depend on it to function properly. Because of this, magnesium helps regulate many aspects of sleep. A meta-analysis of seven clinical trials found that magnesium supplements overall help people sleep better, with higher doses typically working best — though magnesium oxide is the least effective form and generally doesn’t help sleep much at all.
Magnesium Balances Neurotransmitters
Magnesium helps regulate neurotransmitters needed for healthy sleep, including GABA, dopamine, serotonin, and melatonin. These neurotransmitters are essential for promoting good sleep quality.
Magnesium Helps Make Melatonin
While melatonin is the more popular sleep supplement, magnesium may actually work better in some cases because it sits upstream, biochemically speaking, with broader impact across multiple sleep-promoting pathways in the body.
Magnesium Helps Reduce Anxiety and Depression
Supplemental magnesium also helps ease anxiety and depression, both of which contribute to poor sleep quality. A review of seven clinical trials concluded that magnesium reduces anxiety symptoms, which may help sleep indirectly by promoting relaxation and a healthier mood.
Magnesium Replaces Losses from Medications
Many common prescription medications deplete the body’s magnesium stores, including diuretics, acid blockers like proton pump inhibitors, antacids, antibiotics, corticosteroids, antiviral medications, ACE inhibitors, breast cancer drugs, and stimulants like Ritalin. Alcohol and sugar deplete magnesium too.
Magnesium Helps Reduce Muscle Cramping and Symptoms of Restless Legs
Magnesium is well known for relaxing muscles and nerves. A clinical trial found that magnesium supplements help reduce nocturnal muscle cramps and improve sleep quality, though results across studies vary depending on dose and form used.
When combined with vitamin B6, magnesium also reduces symptoms of restless legs. If restless legs is an ongoing issue for you, it’s also worth checking your iron levels.
Magnesium Helps Primary Insomnia
Primary insomnia involves ongoing difficulty falling asleep, staying asleep, or getting restorative sleep, without an identifiable underlying cause. Magnesium supplements have been shown to improve sleep quality and even melatonin levels in elderly adults with primary insomnia. Cortisol and renin levels dropped in this same study, suggesting magnesium’s benefits extend well beyond sleep alone.
Magnesium Helps Overall Health
Magnesium’s benefits go beyond sleep. It helps reduce IBS symptoms, supports heart health, promotes healthy blood pressure, reduces depression symptoms, and may help prevent premature aging.
Magnesium Supplement for Sleep: My Review
Over the years, I’ve tried many forms, brands, and types of magnesium. Every one of them has helped to some degree, with the exception of magnesium oxide.
Magnesium glycinate and magnesium threonate are the two forms I recommend most for sleep, since glycine and threonate each independently support sleep quality on top of the magnesium itself. I personally love magnesium glycinate paired with L-theanine. Magnesium citrate is another inexpensive, effective option, though it can cause loose stools in some people.
My pick for the best magnesium supplement for sleep is Presleep Magnesium, which combines 3 grams of glycine, 500 mg of L-theanine, and 500 mg of magnesium as magnesium glycinate in one nightly drink.
No magnesium supplement will fully overcome bad sleep habits — even a small amount of caffeine, taken earlier in the day, can disrupt REM sleep at night. That said, Presleep has worked remarkably well for me. I’ve used it for about a month, and I’ve noticed I’m far less likely to be woken by household noise. My sleep duration has increased to roughly 8.5–9 hours, which feels like the right amount for me personally, and I’ve even slept in until 6:30–7:00 a.m. a few times, which I haven’t done in years.
I was initially concerned that mixing Presleep with water before bed would mean more nighttime bathroom trips, but the opposite has been true — the magnesium seems to relax my bladder rather than irritate it. It’s best to take magnesium supplements within an hour of bedtime, and with a powder like this, give it at least 15 seconds to fully dissolve.
Other ingredients in Presleep include citric acid for flavor, spirulina for natural color, stevia as a natural sweetener, and silicon dioxide, a safe anti-caking compound.
Magnesium Glycinate Benefits
Magnesium glycinate pairs magnesium with glycine, a calming amino acid that crosses the blood-brain barrier and helps promote deep, restorative sleep. It’s one of the gentlest, best-absorbed forms of magnesium, which is why it’s my go-to recommendation for most people starting out.
I’ve written a full head-to-head comparison of magnesium glycinate against magnesium threonate — covering dosage, anxiety, brain health, and which one is right for your specific goal — in my complete guide: Magnesium Threonate vs. Magnesium Glycinate: Which Is Better for Sleep (and Everything Else)?
Magnesium Threonate Benefits for Sleep
Magnesium L-threonate is a specialty form developed by MIT researchers specifically to raise magnesium levels in the brain. A 2024 randomized controlled trial found that 1 gram per day for 21 days improved sleep quality, deep and REM sleep stages, mood, and daytime alertness compared to placebo — making it a compelling option if a busy, racing mind is what’s keeping you up rather than physical tension.
For the full breakdown of how threonate stacks up against glycinate — including dosing, cost, and whether you should combine the two — see my complete guide: Magnesium Threonate vs. Magnesium Glycinate: Which Is Better for Sleep (and Everything Else)?
Buy Magnesium Threonate on Fullscript
L-Theanine Benefits for Sleep
Another beneficial ingredient in Presleep is L-theanine, an amino acid naturally found in green and black tea. It’s well known for easing anxiety and is often used to help people relax; it also supports immunity and may reduce sugar cravings.
Research shows that combining magnesium and L-theanine increases dopamine, serotonin, and melatonin levels while reducing free radicals and boosting antioxidant enzyme activity. This combination has been shown to improve the speed of falling asleep and total sleep duration. On its own, L-theanine has also been shown to increase sleep duration, and a review of nearly 500 people found it improved sleep quality at doses ranging from 50–655 mg, with higher doses potentially working against sleep quality.
Risks of Magnesium Supplements
Supplemental magnesium is safe for most healthy people at typical doses. As a rule of thumb, follow package directions, and know that true magnesium overdoses are very rare.
Higher doses can cause digestive discomfort such as nausea, diarrhea, or cramps, though the forms discussed above are less likely to cause side effects than magnesium oxide or magnesium chloride.
