Comparison
Magnesium L-Threonate vs MOTS-c
Side-by-side of Magnesium L-Threonate and MOTS-c. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Magnesium L-Threonate
Magnesium l-threonate (Magtein) crosses the blood-brain barrier. Typical dose 1,500-2,000 mg. Sleep and cognitive trial data, side effects.
MOTS-c
MOTS-c peptide is a 16-amino-acid mitochondrial-derived peptide. Preclinical signals for insulin sensitivity, exercise capacity, dosage notes.
Effects at a glance
Magnesium L-Threonate
- •Distinct magnesium salt designed for blood-brain barrier penetration; not a higher-quality systemic magnesium
- •Liu 2010 rodent study: elevated CSF magnesium ~15% and increased hippocampal synaptic density
- •Trial portfolio in humans is small and mostly Magtein-funded; cognitive effects are modest where reported
- •Typical dose 1500 to 2000 mg/day delivers only ~108 to 144 mg of elemental magnesium
- •GI tolerability comparable to other magnesium forms; loose stools in a minority at 2000 mg/day
- •Distinct from magnesium glycinate, which is the conventional sleep/anxiety/repletion form
MOTS-c
- •16-amino-acid peptide encoded in mitochondrial DNA (12S rRNA region); discovered 2015
- •Activates AMPK in skeletal muscle and liver; improves insulin sensitivity in rodent models
- •Circulating endogenous levels decline with age, motivating the longevity-restoration hypothesis
- •CohBar's MOTS-c analog CB4211 discontinued after phase 1b NASH readout did not meet endpoints
- •Anecdotal protocols use 5 to 10 mg subcutaneously 2 to 3 times weekly
- •Not on the WADA Prohibited List as of 2026; future scrutiny likely given exercise-mimetic mechanism
Side-by-side
| Attribute | Magnesium L-Threonate | MOTS-c |
|---|---|---|
| Category | supplement | peptide |
| Also known as | Mg-T, MgT, Magtein, magnesium threonate | Mitochondrial Open Reading Frame of the Twelve S rRNA-c, MOTSc |
| Half-life (hr) ↗ | 4 | 0.5 |
| Typical dose (mg) ↗ | 2000 | 5 |
| Dosing frequency | 1 to 3 times daily | 2-3x weekly |
| Routes | oral | subcutaneous |
| Onset (hr) | 1 | 1 |
| Peak (hr) | 2 | 4 |
| Molecular weight | 294.5 | 1880.18 |
| Molecular formula | C8H14MgO10 | C82H132N22O25S2 |
| Mechanism | Proposed to deliver magnesium across the blood-brain barrier more effectively than other oral salts via threonate-related transporters, raising CNS magnesium and modulating NMDA receptor function and synaptic plasticity. | Mitochondrial-derived peptide that activates AMPK in skeletal muscle and liver, improves insulin sensitivity, and translocates to the nucleus under metabolic stress to modulate nuclear gene expression in retrograde mitochondrial signaling. |
| Legal status | OTC dietary supplement | Not FDA approved; research-use-only grey market; not currently on WADA Prohibited List |
| WADA status | allowed | unknown |
| DEA / Rx | OTC supplement (not scheduled) | Not scheduled (research chemical) |
| Pregnancy | Standard magnesium safety; Mg-T-specific data limited | Insufficient data; not recommended |
| CAS | 778571-57-6 | 1627580-64-6 |
| PubChem CID | 10691810 | 139599184 |
| Wikidata | Q27151568 | Q24832108 |
Safety profile
Magnesium L-Threonate
Common side effects
- loose stools
- mild GI upset
- headache (rare)
- fatigue (rare)
Contraindications
- severe renal impairment (eGFR below 30)
- hypermagnesemia
- myasthenia gravis (high doses)
- concurrent IV magnesium therapy
Interactions
- tetracyclines and fluoroquinolones: magnesium chelation reduces antibiotic absorption; separate by 2 to 4 hours(moderate)
- bisphosphonates: reduced absorption; separate by 2 hours minimum(moderate)
- muscle relaxants and aminoglycosides: potentiated neuromuscular blockade at high doses(moderate)
- antihypertensives: additive blood pressure reduction at high doses(minor)
MOTS-c
Common side effects
- injection-site irritation
- transient fatigue
- headache (anecdotal)
Contraindications
- pregnancy
- lactation
- active malignancy (theoretical)
- severe hypoglycemia risk on concurrent insulin or sulfonylurea
Interactions
- insulin: additive insulin sensitization may increase hypoglycemia risk(moderate)
- metformin: both activate AMPK; theoretical additive metabolic effect, no controlled data(minor)
- sulfonylureas: increased hypoglycemia risk via additive insulin sensitization(moderate)
Which Should You Take?
Magnesium L-Threonate comes out ahead for most readers on the criteria we weight: 2 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-B outcome catalogued. MOTS-c is the right call when one of the conditionals below applies.
- → If your priority is focus or working memory, pick Magnesium L-Threonate.
- → If your priority is sleep onset or sleep quality, pick Magnesium L-Threonate.
- → If your priority is healthspan extension, pick MOTS-c.
- → If your priority is metabolic health and glucose control, pick MOTS-c.
Edge case: If you want to avoid research-only / gray-market sourcing, Magnesium L-Threonate is the more accessible choice.
Default choice: Magnesium L-Threonate. Lower friction to source, and broader goal coverage. Reach for MOTS-c only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Magnesium L-Threonate and MOTS-c?
Magnesium L-Threonate and MOTS-c differ in category (supplement vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Magnesium L-Threonate or MOTS-c?
Magnesium L-Threonate half-life is 4 hours; MOTS-c half-life is 0.5 hours.
Can you stack Magnesium L-Threonate with MOTS-c?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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