Magnesium Glycinate vs Threonate: Which Is Better?

Mike HartnettEvidence-Based

7+ years researching longevity protocols. Runs a 20+ supplement daily stack. Built CoreStacks after losing his father to heart disease.

Last Updated: March 2026

I take both of these. Every day. And I still think most people only need one. Magnesium glycinate and magnesium threonate are the two forms that actually get recommended by longevity doctors — Huberman takes both, Attia recommends glycinate for sleep — but they do different things, and one of them costs 4x more than the other. I’ve run my own side-by-side test: glycinate only for 6 weeks, threonate only for 6 weeks, then both together. The sleep data from my Oura ring told a clear story. If you’re trying to pick one and don’t want to waste money, this comparison gives you the straight answer.

Magnesium Glycinate vs Threonate: Which Form Should You Take?

Magnesium glycinate is the better choice for most people. It offers strong bioavailability, supports sleep and relaxation through its glycine component, addresses general magnesium deficiency, and costs significantly less than alternatives. Magnesium threonate (sold as Magtein) may be a better option specifically for cognitive function because it is the only form shown in published research to meaningfully increase magnesium concentrations in the brain by crossing the blood-brain barrier. Dr. Andrew Huberman takes both: threonate for cognition and glycinate for sleep, as separate supplements in his evening routine. For most people starting out, glycinate alone covers the largest number of benefits at the lowest cost.

Magnesium Glycinate: The All-Around Choice

Magnesium glycinate is magnesium chelated with the amino acid glycine. This chelation gives it high bioavailability, meaning your body absorbs a large percentage of the elemental magnesium in each dose. It is also well-tolerated, with far fewer gastrointestinal side effects than oxide or citrate forms.

The glycine component adds its own benefits. Research published in the Journal of Pharmacological Sciences found that glycine improved subjective sleep quality and reduced core body temperature, a key trigger for sleep onset. This dual action makes glycinate particularly effective as an evening supplement.

Best for: Sleep quality, general magnesium repletion, muscle relaxation, stress reduction, daily supplementation on a budget.

Typical dose: 200 to 400 mg elemental magnesium per day.

Magnesium Threonate: The Brain-Specific Option

Magnesium L-threonate was developed at MIT and patented as Magtein. Its distinguishing feature is a 2010 study published in Neuron showing that it elevated brain magnesium levels more effectively than other forms tested, including glycinate and citrate. The researchers found that increased brain magnesium enhanced synaptic density and improved learning and memory in both young and aged animal models.

A 2016 human trial published in the Journal of Alzheimer’s Disease found that Magtein supplementation improved cognitive abilities in older adults with mild cognitive impairment, with particular improvements in executive function and working memory. Dr. Huberman has cited this research on the Huberman Lab podcast as his rationale for including threonate specifically for cognitive support.

Best for: Cognitive function, memory support, focus, age-related cognitive concerns.

Typical dose: 1,500 to 2,000 mg of magnesium L-threonate per day (providing roughly 96 to 144 mg elemental magnesium).

Head-to-Head Comparison

What the Experts Do

Dr. Andrew Huberman takes both forms as separate supplements: magnesium threonate and magnesium glycinate (or bisglycinate) 30 to 60 minutes before bed. He has explained on the Huberman Lab podcast that threonate targets brain magnesium for cognitive function while glycinate supports broader relaxation and sleep through the glycine pathway.

For a full breakdown of every magnesium form, dosing, and timing strategy, read our complete magnesium supplementation guide.

Dr. Peter Attia has discussed magnesium on The Drive podcast and emphasizes that correcting deficiency should be the first priority. Since threonate delivers relatively low elemental magnesium, Attia’s approach focuses on ensuring adequate total magnesium intake, which glycinate handles more efficiently per capsule.

Practical Recommendation

If you are choosing one form, start with magnesium glycinate. It provides more elemental magnesium per dose, costs 3 to 5 times less than threonate, has a larger research base, and addresses the broadest range of deficiency symptoms including poor sleep, muscle cramps, and stress. If cognitive function is a specific concern and budget allows, add threonate as a second supplement rather than replacing glycinate with it.

Ready to pick a product? See our best magnesium glycinate supplements, all independently tested for purity and elemental magnesium content.

For the complete guide to all magnesium forms and dosing strategies, see our Magnesium Supplementation Guide (2026). If you are ready to buy, see our top picks in Best Magnesium Glycinate Supplements for 2026.

Frequently Asked Questions

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• Signs of magnesium deficiency

Frequently Asked Questions

Can I take glycinate and threonate together?

Yes. Many people take both, and Huberman does exactly this. They address different needs through different mechanisms. Take them at the same time in the evening or split them if you prefer threonate earlier in the day for cognitive support and glycinate closer to bedtime.

Does threonate help with sleep too?

Some users report improved sleep with threonate, but the published research focuses on cognitive outcomes rather than sleep. If sleep is your primary goal, glycinate has stronger direct evidence. Threonate’s lower elemental magnesium content also means it is less effective at correcting overall magnesium deficiency, which is often an underlying cause of poor sleep.

This article reports what published research and named experts have publicly shared. It is not medical advice. Consult a qualified healthcare provider before starting any supplement regimen.