Magnesium L-Threonate

Also known as: magtein

Grade B — Moderate Evidencemineralcognitive
1000–2000 mgEvening or split AM/PM

Magnesium L-Threonate (branded as Magtein) is the only form of magnesium demonstrated to significantly increase magnesium levels in the brain by crossing the blood-brain barrier. Developed at MIT, this form has shown promise for cognitive enhancement, memory support, and potentially slowing age-related cognitive decline. While more expensive than other magnesium forms, it fills a unique niche for brain-targeted supplementation.

TL;DR: The only magnesium form shown to cross the blood-brain barrier effectively. Promising for cognitive function and brain aging.

🧠Cognitive Performance🎯Focus🌙Sleep
Last reviewed: 2026-03-12

Quick Facts

Evidence

Grade B

Studies

1

Interactions

1

Forms

3

Evidence Rating: Grade B — Moderate Evidence

Some RCTs with positive results, or strong observational evidence. More research may refine our understanding.

Forms Comparison

Magnesium L-Threonate

✓ High Absorption

Only form shown to significantly cross the blood-brain barrier. Premium priced.

cognitive functionbrain agingmemory

Magnesium Glycinate

✓ High Absorption

Chelated with glycine for high absorption and calming effect.

sleepanxietygeneral deficiency

Magnesium Citrate

~ Moderate Absorption

Good bioavailability and affordable. Mild laxative effect.

constipationgeneral supplementation

Interaction Warnings

AntibioticsModerate

Separate by 2 hours

Important Notes

  • More expensive than other magnesium forms

Clinical Evidence (1 study)

Enhancement of learning and memory by elevating brain magnesium

Bhatt DK et al. (2010) — Neuron

MgT uniquely crosses BBB and enhances synaptic density

View on PubMed

Alternatives to Consider

These supplements target similar goals and may be worth considering alongside or instead of Magnesium L-Threonate.

Huperzine A

Grade B

Potent acetylcholinesterase inhibitor. Effective for memory but narrow therapeutic window — cycling and careful dosing required.

🧠 Cognitive Performance🎯 Focus

L-Tyrosine

Grade B

Amino acid precursor to dopamine, norepinephrine, and thyroid hormones. Best evidence is for maintaining cognitive performance under stress, sleep deprivation, and multitasking. Take on empty stomach.

🎯 Focus🧠 Cognitive Performance

Magnesium Glycinate

Grade A

Highly bioavailable form of magnesium. Strong evidence for sleep quality, muscle relaxation, and stress reduction. Most adults are deficient.

🌙 Sleep

Related Supplements

L-Theanine

Grade B — Moderate Evidence

Amino acid from green tea. Promotes calm focus (alpha brain waves) without drowsiness. Excellent safety profile.

Huperzine A

Grade B — Moderate Evidence

Potent acetylcholinesterase inhibitor. Effective for memory but narrow therapeutic window — cycling and careful dosing required.

L-Tyrosine

Grade B — Moderate Evidence

Amino acid precursor to dopamine, norepinephrine, and thyroid hormones. Best evidence is for maintaining cognitive performance under stress, sleep deprivation, and multitasking. Take on empty stomach.

Lion's Mane

Grade B — Moderate Evidence

Medicinal mushroom that stimulates NGF. Multiple RCTs show benefits for mild cognitive impairment and mood.

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⚕️ Important Disclaimer

This information is for educational purposes only. It is not medical advice. Always consult a healthcare provider before starting any supplement regimen, especially if you take medications or have health conditions.

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