Magnesium L-threonate is a low-elemental magnesium salt promoted for brain delivery. The frequently cited increase in cerebrospinal-fluid magnesium comes from animals; human trials have not directly measured higher brain or CSF magnesium after oral use.
What it is, why people use it, the evidence, and what to know before trying it.
Regulatory status: supplement (oral mineral / organic salt). Not a prescription drug. Not a device, habit, or measurement. Neurocentria is developing the same ligand as a drug candidate (MMFS / L-TAMS) for ADHD, depression, and Alzheimer’s — that is a different regulatory track from the OTC Magtein bottle
Evidence basis: Animal research
Known side effects, interactions and use limits from reviewed sources.
Human safety evidence is limited and mostly short term. Magnesium supplements can cause diarrhea and may accumulate with significant kidney impairment; they can also reduce absorption of some antibiotics and other medicines when taken together.
This review does not automatically apply to:
Public protocols that include Magnesium L-threonate. Open one to see the full context and source.
Offered as an either/or with 200 mg magnesium bisglycinate. Newsletter wording is "You might consider taking"; he added he uses Momentous for all of them (affiliate). Toolkit for Sleep, 20 Sep 2021.
Milligrams not stated; counted inside the ~1 g elemental magnesium item in the daily-supplements protocol. The Drive
daily · night (implied by the sleep portion of his roll call)
Dose not stated. Brand Momentous is from 2024 affiliate copy and was not restated in 2025. Merged from the daily-supplements protocol on 2026-09-02.
Amount and timing patterns reported in public protocols; these are observations, not instructions. Private and hidden usage is excluded.
daily
Brand variants reported in public protocols. Private entries are excluded, and inclusion is not an endorsement.
Continue into interventions that appear alongside this one.