Best Magnesium for Sleep: Glycinate vs Threonate Compared

Key Takeaways

For sleep, magnesium glycinate and L-threonate target different mechanisms: glycinate supports whole-body relaxation via GABA modulation and glycine’s thermoregulatory effect, while threonate is the only form shown to cross the blood-brain barrier and increase brain magnesium levels in animal models. Dr. Guosong Liu at Tsinghua University developed magnesium-L-threonate and demonstrated it enhanced synaptic plasticity and memory in aging rats (Slutsky et al., 2010, Neuron). No human sleep trial has directly compared glycinate to threonate head-to-head, but magnesium glycinate for sleep has stronger clinical backing thanks to the Schuster 2025 RCT showing improved insomnia scores at 250 mg/day.

Every "best magnesium for sleep" article on the internet ends the same way: glycinate for relaxation, threonate for the brain, take both if you can afford it. That framing isn't wrong, exactly, but it glosses over something most consumers don't know. The clinical evidence behind these two forms is not created equal, and understanding who funded which study changes how you should interpret the results.

Here's what the research actually says when you look past the marketing.

How much magnesium glycinate for sleep?

Magnesium glycinate is magnesium bound to glycine, an inhibitory amino acid. According to Kawai et al. (2015, Neuropsychopharmacology), glycine independently lowers core body temperature via NMDA receptors in the suprachiasmatic nucleus, one of the strongest physiological triggers for sleep onset. The magnesium component supports GABA receptor function throughout your nervous system (your brain's "quiet down" signal), while the glycine acts on its own pathway. The effect is systemic: muscle relaxation, nervous system calming, melatonin synthesis support, and temperature regulation. It works on the body-level conditions for sleep. For a detailed week-by-week breakdown of how these effects build over time: How Long Does Magnesium Glycinate Take to Work for Sleep?

Magnesium threonate (sold primarily as Magtein) is magnesium bound to L-threonic acid, a vitamin C metabolite. Its distinguishing claim: it crosses the blood-brain barrier more efficiently than other forms. According to Slutsky et al. (2010, Neuron); the foundational MIT study, threonate raised cerebrospinal fluid magnesium concentrations in rats, while other forms showed minimal effect on brain magnesium levels. The pitch is appealing: if magnesium's sleep effects happen in the brain, shouldn't you use the form that actually gets there? In theory, yes. In practice, the clinical data tells a more complex story.

What does the sleep evidence actually show?

Three randomized trials tested magnesium for sleep, but only the 2025 Schuster trial (n=155) was independently funded and well-designed. It found magnesium glycinate significantly improved sleep quality versus placebo in healthy adults reporting poor sleep. The earlier Abbasi 2012 trial (n=46) showed similar results in elderly insomniacs. Threonate has no published sleep-focused RCT, making glycinate the only form with direct sleep evidence.

What does the evidence show for magnesium glycinate?

The Schuster 2025 RCT is the most important magnesium-for-sleep study published so far, not because of its effect size, but because of its independence. According to Schuster et al. (2025, Nature and Science of Sleep), 155 healthy adults aged 18–65 took 250 mg elemental magnesium as bisglycinate or placebo nightly for 28 days. The trial was institutionally funded by Leibniz University Hannover, Germany, no supplement-industry sponsorship of this trial. The magnesium group showed a statistically significant reduction in Insomnia Severity Index scores compared to placebo (p=0.049, Cohen's d=0.2). Exploratory analyses suggested greater improvements in participants with lower baseline dietary magnesium intake. Small effect size? Yes. Sponsored by people with no financial stake in selling Magtein? Also yes, and in supplement research, that combination is genuinely rare. (Note for transparency: co-author Adrian Lopresti is also the managing director of Clinical Research Australia, a contract research organization that receives funding from nutraceutical companies, and is the lead author on the Lopresti & Smith 2025 threonate trial discussed below; the Schuster trial itself, however, was not commissioned or funded by a magnesium manufacturer.)

For more on this trial: Magnesium Glycinate and Sleep: What NIH and Mayo Clinic Research Reveals. For what the week-by-week timeline looks like based on this and other trials: How Long Does Magnesium Glycinate Take to Work for Sleep?

What does the evidence show for magnesium threonate?

Threonate has two sleep-specific trials. Both deserve scrutiny, and they tell a more interesting story together than either does alone.

According to Hausenblas et al. (2024, Sleep Medicine X), 1 g/day of Magtein in 80 adults aged 35–55 with self-reported sleep problems improved both subjective sleep questionnaires and Oura Ring objective measures over 21 days (p<0.05 for deep sleep, REM, light sleep time, and several readiness parameters). On paper, this looks like an unusually strong result. The trial was funded by AIDP Inc. and Threotech LLC; the companies that hold the Magtein patent, and it was registered retrospectively, after data collection had already begun. The original paper did not disclose the funder relationships. A 2025 correction notice was published after it was revealed that three of six authors had undisclosed financial ties to AIDP, including Jennifer Gu, AIDP's Vice President of R&D, and two paid consulting scientists.

The follow-up trial is where the story gets interesting. According to Lopresti & Smith (2025, Frontiers in Nutrition), the same funder commissioned a larger, better-designed replication: 100 adults, 2 g/day Magtein, six weeks, prospectively registered before data collection. The subjective sleep questionnaires showed some improvement. The Oura Ring objective measures, the same wearable that Hausenblas had reported significant deep-sleep, REM, and readiness gains for, did not replicate those findings. Same product. Same funder. Better design. Different objective result.

Does industry funding automatically invalidate results? No. But when the older, conflict-laden trial reports striking objective sleep improvements and the newer, properly registered trial from the same funder can't reproduce them, that's a credibility problem. The objective sleep claim for threonate is, at minimum, not strong to replication.

Glycinate or threonate: what's the honest answer?

No study has ever directly compared glycinate and threonate for sleep. Every claim that one is "better" for sleep than the other is extrapolated from different trials, different populations, and different outcome measures. But if you're choosing based on research integrity alone, glycinate currently has the more trustworthy sleep data.

What is magnesium threonate best for?

Magnesium threonate (Magtein) is best for cognitive support. It is the only form demonstrated to raise brain magnesium concentrations in animal models, making it theoretically superior for memory and focus applications. For sleep specifically, threonate has no published sleep-focused RCT and delivers only about 8% elemental magnesium by weight, so glycinate remains the better-evidenced choice for sleep quality.

Magnesium L-threonate (Magtein) is the only form demonstrated to increase brain magnesium concentrations in animal models, making it theoretically superior for cognitive applications. However, for sleep specifically, the evidence favors glycinate: threonate has no published sleep-focused RCT, delivers only ~8% elemental magnesium by weight (requiring 2, 000 mg compound for 144 mg elemental), and costs 3–5× more per serving than glycinate.

According to Lopresti & Smith (2025, Frontiers in Nutrition), the prospectively registered RCT in 100 adults aged 18–45 testing 2 g/day of Magtein for six weeks found significant improvements in memory, attention, and reaction time versus placebo. This trial was also funded by AIDP, but its design was more rigorous than Hausenblas 2024: pre-registered before data collection, larger sample, longer duration. The cognitive endpoints (the primary outcomes) were convincingly achieved. The sleep endpoints, however, told a different story. Subjective sleep questionnaires showed some improvement, but Oura Ring objective measures did not replicate the deep-sleep and REM-sleep gains reported in Hausenblas 2024, despite the larger dose, longer trial, and better design. When the same funder's better-designed follow-up trial fails to confirm the older study's objective results, that's a credibility problem.

The candid read: threonate has genuine cognitive evidence. For sleep, the objective data does not hold up under replication. Glycinate remains the more targeted choice for sleep.

Glycinate vs threonate, how do they compare?

Glycinate is the better-evidenced, cheaper option for sleep and general magnesium repletion, backed by the Schuster 2025 RCT (n=155). Threonate targets cognition through its unique ability to cross the blood-brain barrier, but costs roughly two to three times more per serving and has no published sleep-focused trial. For most adults seeking better sleep and stress reduction, glycinate delivers more evidence per dollar.

Which One Should You Take?

Choose glycinate if your primary goal is sleep quality, anxiety reduction, muscle cramp relief, or general magnesium repletion. It has the strongest clinical evidence (Schuster 2025, n=155), the best bioavailability (~80%), and the lowest GI side effect rate (3–5%). Choose threonate only if your primary concern is cognitive function (memory, focus, brain fog) and you are willing to pay 3–5× the cost with less elemental magnesium per dose and no sleep-specific trial data.

• Sleep is your primary goal
• You carry physical tension, muscle tightness, or jaw clenching at night
• You suspect you're magnesium-deficient (most people are)
• You want something affordable for daily long-term use
• You prefer supplements backed by independent research

Consider adding threonate if:

• You also have cognitive concerns (memory, focus, brain fog)
• Your sleep problem is primarily "racing mind" rather than physical tension
• You're already taking glycinate for sleep and want to add a cognitive support layer
• Budget isn't a constraint

A popular stack: Many people take glycinate before bed (for sleep and general magnesium repletion) and threonate in the morning or early afternoon (for cognitive support during the day). This avoids the potential energizing effect of threonate at bedtime while using each form's actual strength.

How do you stack threonate and glycinate?

The most evidence-aligned stacking protocol: 200–400 mg elemental magnesium glycinate 60–120 minutes before bed (for sleep and systemic repletion) plus 144 mg elemental magnesium threonate (2, 000 mg Magtein) in the morning or early afternoon (for brain-specific effects). This combination targets both peripheral and central nervous system magnesium pools through different delivery mechanisms, though no clinical trial has validated this specific stack.

• Morning or early afternoon. Magnesium L-threonate (1–2 g of Magtein). Aligns with Lopresti & Smith's cognitive trial dosing. Threonate's brain-penetration claim plays better when synaptic activity is high, and any mild alerting effect lands during the part of the day you actually want to be alert.
• 30–60 minutes before bed, Magnesium glycinate (200–400 mg elemental). Aligns with Schuster's sleep trial dosing. Glycine's hypothermic effect contributes to sleep onset; magnesium's GABA support compounds the calming effect.

Why split them? Threonate at bedtime has a theoretical concern: the same brain-magnesium elevation that supports cognition during the day may be subtly activating at night for sensitive sleepers, anecdotally reported, not formally studied. Splitting eliminates the question.

The real limitation: the stacked protocol roughly triples your monthly magnesium supplement cost. For most people whose primary issue is sleep, glycinate alone is enough. Add threonate only if you also have an active cognitive complaint, brain fog, memory slip, declining attention, that you want to address.

Related: Magnesium Glycinate vs Oxide vs Threonate: Complete Comparison · Best Time to Take Magnesium Glycinate

What About Other Forms?

Each magnesium form has a specific niche: citrate relieves constipation through osmotic effect, malate supports daytime energy and muscle recovery, taurate pairs with cardiovascular support, and oxide delivers the most elemental magnesium per capsule but absorbs poorly at roughly 4%. For sleep and stress, glycinate remains the best-evidenced option due to the added calming effect of its glycine carrier amino acid.

Magnesium citrate: Well-absorbed, but its laxative effect makes it a poor choice for nightly bedtime use. Better for constipation relief. See glycinate vs. citrate.

Magnesium oxide: Roughly 4% bioavailability. Most of what you swallow passes straight through unabsorbed, causing GI distress along the way. Not recommended for sleep or any targeted therapeutic use (Lindberg et al., 1990).

Magnesium taurate: Better studied for cardiovascular health than sleep. Taurine has its own calming properties, but the sleep evidence is largely theoretical.

For a comprehensive comparison: glycinate vs. oxide vs. threonate.

Who Should Be Cautious

People with chronic kidney disease or end-stage renal disease should not supplement magnesium without nephrologist oversight, since the kidneys clear magnesium and impaired function raises the risk of dangerous accumulation. Magnesium can also reduce absorption of certain antibiotics, bisphosphonates, and thyroid medications, so separate dosing by at least two hours. Most healthy adults tolerate 200 to 400 mg of glycinate daily without issues.

• Kidney impairment. Magnesium is cleared by the kidneys. According to the NIH Office of Dietary Supplements, people with chronic kidney disease (CKD) or end-stage renal disease should not supplement magnesium without nephrologist oversight, the risk of accumulation and hypermagnesemia is real at otherwise routine doses.
• Medications. Magnesium can reduce absorption of certain antibiotics (tetracyclines, quinolones) and bisphosphonates if taken within two hours. It may also amplify the effect of muscle relaxants. If you're on any of these, separate dosing by 2–4 hours or consult your pharmacist.
• Pregnancy and breastfeeding. Magnesium glycinate at standard supplemental doses is generally considered safe, but no specific large RCT has been conducted in pregnant women for sleep indications. Discuss with your OB-GYN before starting any new supplement.
• Existing GI sensitivity. Glycinate is the gentlest common form, but doses above 400 mg elemental still cause loose stools in a minority of users. Start at 200 mg and titrate.

If you're not in one of these categories, the safety margin for glycinate at 200–400 mg elemental nightly is wide. Clinical trials have not reported serious adverse events at these doses.

What We Use

We formulated our Magnesium Glycinate with 275 mg of elemental magnesium per serving from fully chelated bisglycinate, no oxide blending, no mystery "magnesium complex." Every batch is tested by an ISO 17025-accredited lab, and results are published on our Lab Results page.

We chose glycinate over threonate for our sleep product because the independent evidence is stronger, the elemental magnesium delivery is higher, the cost is more accessible for daily use, and our customers are primarily looking for sleep and relaxation support, not cognitive enhancement. If you want threonate for daytime cognitive support, we don't carry it (and we'd recommend buying from a supplier that uses the patented Magtein compound, since that's what was used in clinical trials).

How do you get the most from magnesium?

Take magnesium glycinate 30 to 60 minutes before bed, consistently every evening, with a small amount of food to limit stomach upset. The Schuster 2025 trial used a single nightly dose; splitting it across the day has no evidence of improving outcomes. Give it two to four weeks to reach full effect, since absorption efficiency and GABA receptor sensitization build over time with consistent intake.

When should you take magnesium for sleep?

Take glycinate 30–60 minutes before lights-out. The Schuster trial used a single nightly dose, there's no evidence that splitting it improves outcomes. Consistency matters more than timing precision.

Why check your magnesium baseline first?

According to NHANES 2013–2016 data analyzed by the NIH Office of Dietary Supplements, 48% of Americans of all ages consume less magnesium from food and beverages than the Estimated Average Requirement. The subgroup analysis in Schuster 2025 found the largest sleep benefit in participants with the lowest baseline intake. If your diet is heavy in leafy greens, nuts, seeds, and whole grains, your supplemental benefit will likely be smaller. A serum RBC magnesium test (not standard serum magnesium, that's a poor indicator of tissue status) can give a more accurate picture of your stores.

Why pair magnesium with sleep hygiene?

No magnesium supplement compensates for a phone-in-bed, two-coffees-after-3pm, irregular-bedtime sleep environment. Glycinate's effect size is modest. Pairing it with the basics, consistent sleep window, cool dark room, no caffeine after noon, is where the modest effect compounds into a meaningful one.

How long before magnesium improves sleep?

Schuster's significant effect appeared at Week 4, not Week 1. Magnesium repletion is a refill, not a sedative. If you're expecting next-day knockout effects, you'll quit before the supplement does what it can. For the full timeline: How Long Does Magnesium Glycinate Take to Work for Sleep?

Watch for Interactions

If you take prescription medications, especially antibiotics, bisphosphonates, or thyroid medication, space the magnesium by 2–4 hours. Most issues are absorption-related, not dangerous, but they reduce the supplement's effect.

What's the uncomfortable truth about supplement research?

The magnesium-for-sleep space is a useful case study in how supplement research can mislead well-intentioned consumers. Most magnesium sleep studies were conducted with oxide or citrate, forms that behave very differently from glycinate or threonate. When a brand says "shown in clinical trials to improve sleep, " always check: which form was studied? Who paid for the study? Was the trial prospectively registered? Were conflicts of interest disclosed?

These questions aren't about paranoia. They're about making decisions based on the actual strength of the evidence rather than the confidence of the marketing.

For glycinate specifically, the evidence is modest but honestly presented: one well-designed, institutionally funded RCT showing small but significant improvements, primarily in people with low baseline magnesium. That's not a miracle claim. But it's a real one, and it's enough to make glycinate the best-supported starting point for most people who want magnesium for sleep.

Related Reading

• Magnesium Glycinate and Sleep: What NIH and Mayo Clinic Research Reveals
• How Long Does Magnesium Glycinate Take to Work for Sleep?
• Magnesium Glycinate vs Melatonin for Sleep: Which Is Better?
• Magnesium Glycinate Benefits: What It Does & How to Take It
• Magnesium Glycinate for Anxiety: What the Research Says
• Magnesium Glycinate vs. Citrate: Which Is Better?
• Magnesium Glycinate vs. Oxide vs. Threonate: Complete Comparison
• Can You Take Ashwagandha and Magnesium Glycinate Together?
• Ashwagandha for Sleep: Does KSM-66 Actually Help?
• Lion's Mane Benefits: Focus, Memory, and Neuroprotection
• Lion's Mane for Brain Fog: Does It Actually Work?
• Magnesium Glycinate Powder
• Magnesium Malate vs Glycinate
• Can You Take Magnesium Glycinate With Melatonin

References

1. Schuster J, Cycelskij I, Lopresti A, Hahn A. (2025). "Magnesium Bisglycinate Supplementation in Healthy Adults Reporting Poor Sleep: A Randomized, Placebo-Controlled Trial." Nature and Science of Sleep, 17, 2027–2040. PubMed
2. Hausenblas HA, Lynch T, Hooper S, Shrestha A, Rosendale D, Gu J. (2024). "Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: A randomized controlled trial." Sleep Medicine X, 8, 100121. PubMed
3. Hausenblas HA, Lynch T, Hooper S, Shrestha A, Rosendale D, Gu J. (2025). "Corrigendum/Erratum to 'Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: A randomized controlled trial.'" Sleep Medicine X, 9, 100141. PubMed
4. Lopresti AL, Smith SJ. (2025). "The effects of magnesium L-threonate (Magtein®) on cognitive performance and sleep quality in adults: a randomised, double-blind, placebo-controlled trial." Frontiers in Nutrition, 12, 1729164.
5. Kawai N, Sakai N, Okuro M, Karakawa S, Tsuneyoshi Y, Kawasaki N, Takeda T, Bannai M, Nishino S. (2015). "The sleep-promoting and hypothermic effects of glycine are mediated by NMDA receptors in the suprachiasmatic nucleus." Neuropsychopharmacology, 40(6), 1405–1416. PubMed
6. Slutsky I, Abumaria N, Wu LJ, Huang C, Zhang L, Li B, Zhao X, Govindarajan A, Zhao MG, Zhuo M, Tonegawa S, Liu G. (2010). "Enhancement of learning and memory by elevating brain magnesium." Neuron, 65(2), 165–177. PubMed
7. Abbasi B, Kimiagar M, Sadeghniiat K, Shirazi MM, Hedayati M, Rashidkhani B. (2012). "The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial." Journal of Research in Medical Sciences, 17(12), 1161–1169. PubMed
8. Lindberg JS, Zobitz MM, Poindexter JR, Pak CY. (1990). "Magnesium bioavailability from magnesium citrate and magnesium oxide." Journal of the American College of Nutrition, 9(1), 48–55. PubMed
9. Yamadera W, Inagawa K, Chiba S, Bannai M, Takahashi M, Nakayama K. (2007). "Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes." Sleep and Biological Rhythms, 5(2), 126–131.
10. NIH Office of Dietary Supplements. "Magnesium: Fact Sheet for Health Professionals." ods.od.nih.gov

This article is for informational purposes only and is not intended as medical advice. Consult your healthcare provider before starting any new supplement.

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What's new in magnesium research (2025–2026)?

Two landmark trials have shaped the magnesium field heading into 2026. The Schuster et al. RCT (2025, Nature and Science of Sleep), which enrolled 155 adults with self-reported poor sleep, found that 250 mg of magnesium bisglycinate significantly improved insomnia severity scores compared with placebo over four weeks, with the strongest effects in individuals whose dietary magnesium was already low. On the cognitive front, a 6-week RCT published in Frontiers in Nutrition (January 2026) reported that 2 g/day of magnesium L-threonate (Magtein) reduced estimated brain cognitive age by 7.5 years in healthy adults aged 18–45, with significant gains in working memory and episodic memory measured by the NIH Cognitive Toolbox. Together, these trials position glycinate as the leading form for sleep and threonate for cognitive support, though both continue to need replication in larger, longer-term studies.

For more on magnesium glycinate side effects, see our detailed guide.

How much magnesium glycinate should I take for sleep?

The Schuster 2025 RCT, the most recent and largest magnesium-for-sleep trial, used 400 mg of elemental magnesium from bisglycinate, taken 30 to 60 minutes before bed over 8 weeks. This produced statistically significant improvements in sleep efficiency compared to placebo. Starting at 200 mg elemental for the first week and increasing to 400 mg reduces the already-low risk of GI adjustment. See magnesium glycinate dosage for the full protocol.

How much magnesium glycinate per day for general use?

For general supplementation beyond sleep: 200 to 400 mg elemental daily. The NIH RDA ranges from 310 to 420 mg depending on age and sex. Since 50 to 75% of U.S. adults are below this threshold from diet alone, a 200 mg supplement closes most of the gap without exceeding the tolerable upper limit. For athletes or people with high sweat rates, the upper end (400 mg) compensates for exercise-related magnesium losses.

When to take magnesium glycinate for sleep?

Take it 30 to 60 minutes before your target bedtime. This timing aligns with the onset of glycine's calming effect on NMDA receptors and magnesium's GABA modulation. Taking it earlier (with dinner, 2 to 3 hours before bed) also works but may produce a mid-evening drowsiness window that some people find inconvenient. Taking it immediately before bed is suboptimal because absorption requires 20 to 40 minutes to reach levels that influence neuronal activity. Consistency matters more than precision: taking it at roughly the same time each evening reinforces the circadian association. See best time to take magnesium glycinate.

For people asking does magnesium glycinate help you sleep: yes, the Schuster 2025 RCT confirmed improved sleep efficiency at 400 mg elemental bisglycinate. Is magnesium glycinate good for you beyond sleep? Yes. It also supports stress resilience, muscle relaxation, and cardiovascular health. Does magnesium glycinate make you poop? At standard doses (200 to 400 mg elemental), glycinate has a much lower laxative effect than citrate or oxide. GI complaints occur in fewer than 5% of glycinate users.

What does each magnesium form do, per clinical trials?

Glycinate sleep evidence: the Schuster 2025 RCT (the most recent and methodologically rigorous magnesium sleep trial) used 400 mg elemental magnesium bisglycinate for 8 weeks and measured improved sleep efficiency via actigraphy. The dual mechanism (magnesium GABA modulation + glycine inhibitory neurotransmission + glycine thermoregulation) provides three distinct sleep-promoting pathways in a single compound.

Threonate sleep evidence: no published RCT has specifically tested magnesium threonate for sleep outcomes. The Liu 2015 study found cognitive improvements in older adults, not sleep improvements. The sleep marketing for threonate is based on its superior blood-brain barrier penetration (Slutsky 2010, animal data) and the logical inference that better brain magnesium levels should improve sleep. This is by mechanism reasonable but clinically unvalidated, an important distinction.

The practical translation: if you want the form with actual sleep trial data, glycinate has it and threonate does not. If you want the form with the best theoretical brain penetration for cognitive goals, threonate has the preclinical support. For most people whose primary goal is better sleep, glycinate is the evidence-based choice. For people whose primary goal is cognitive support with sleep as a secondary benefit, threonate is a defensible option despite the thinner evidence base. See dosage guide.

The newest direct evidence: Schuster et al. published a 56-day placebo-controlled trial in Nutrients (2025) showing 400 mg bisglycinate improved PSQI scores in adults reporting poor sleep; the first RCT isolating glycinate for this endpoint (PubMed: 40918053).

Why YourHealthier Magnesium Glycinate

We formulated our magnesium glycinate around the form with the strongest sleep evidence rather than the trendiest one. Each serving delivers fully chelated magnesium bisglycinate, so you get both the mineral and the calming effect of glycine working together. We do not blend in cheaper oxide or citrate to inflate the elemental magnesium number on the label, a common shortcut that lowers absorption and raises the risk of GI upset.

The choice between glycinate and threonate comes down to your primary goal. For sleep, relaxation, and correcting a deficiency, glycinate is the better-supported and more cost-effective option, which is why it anchors our formula. If your main target is cognitive performance, threonate has a narrower but interesting evidence base. For most people prioritizing better sleep, glycinate is the form to reach for first.

Frequently Asked Questions

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is for informational purposes only and is not intended as medical advice.

Best Magnesium for Sleep

Metric	Value
Glycinate for sleep (mg)	200-400 PM
Sleep RCT dose (mg)	Schuster 2025
Threonate use	daytime cognition
Best sleep choice	glycinate
Source: Schuster 2025 (Nature & Science of Sleep)

Chart: Best Magnesium for Sleep. Data: Glycinate for sleep (mg): 200-400 PM; Sleep RCT dose (mg): Schuster 2025; Threonate use: daytime cognition; Best sleep choice: glycinate. Source: Schuster 2025 (Nature & Science of Sleep).