Comparison
Magnesium Glycinate vs Spermidine
Side-by-side of Magnesium Glycinate and Spermidine. 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 Glycinate
Magnesium glycinate supplement guide: chelated bisglycinate form, 200 to 400 mg dosage, sleep architecture benefits, low GI side effects, glycine co-effect.
Spermidine
Spermidine supplement benefits cover autophagy induction, longevity signals, and cognition. Wheat germ extract data, doses, and human trials reviewed.
Effects at a glance
Magnesium Glycinate
- •Shortens sleep onset latency in older adults and in deficient populations supplementing 200 to 400 mg elemental Mg
- •Improves subjective sleep quality scores (PSQI, ISI) modestly versus placebo over 4 to 8 weeks
- •Reduces nocturnal leg cramps and exercise-induced muscle cramping in some controlled trials
- •Lowers self-reported anxiety in mild-to-moderate cases, with smaller effect than first-line pharmacotherapy
- •Glycinate form delivers fewer GI side effects than oxide or citrate at equivalent elemental doses
- •Insufficient as a stand-alone hypertension treatment; small adjunctive blood-pressure reductions only
Spermidine
- •Endogenous polyamine that induces autophagy via EP300 acetyltransferase inhibition and TFEB activation
- •Concentrated in wheat germ, soybeans, aged cheese, and mushrooms; ~10 to 15 mg/day in Mediterranean diets
- •Eisenberg 2016 reported dietary spermidine extended mouse lifespan and improved cardiac function
- •Wirth 2018 pilot (n=28) reported cognitive signal at 0.9 mg/day in older adults at risk for dementia
- •Larger Wirth 2019 follow-up (n=85) did not replicate the memory benefit at 12 months
- •Generally regarded as safe at supplemental doses; food-source position is reassuring
Side-by-side
| Attribute | Magnesium Glycinate | Spermidine |
|---|---|---|
| Category | supplement | supplement |
| Also known as | magnesium bisglycinate | spermidine trihydrochloride, wheat-germ-extract spermidine |
| Half-life (hr) ↗ | 5 | 6 |
| Typical dose (mg) ↗ | 300 | 1.2 |
| Dosing frequency | daily (often evening) | daily, typically morning with food |
| Routes | oral | oral |
| Onset (hr) | 1 | 2 |
| Peak (hr) | - | 4 |
| Molecular weight | - | 145.25 |
| Molecular formula | - | C7H19N3 |
| Mechanism | Magnesium acts as a cofactor for 300+ enzymes and as a voltage-dependent antagonist at NMDA receptors; glycine serves as an inhibitory neurotransmitter and co-agonist at glycine receptors. | Induces macroautophagy via inhibition of EP300 histone acetyltransferase and activation of TFEB-mediated lysosomal biogenesis. Substrate for hypusination of eIF5A, required for translation of mitochondrial respiration proteins. |
| Legal status | Dietary supplement | OTC dietary supplement (wheat-germ extract has GRAS status in US) |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement | OTC supplement (not scheduled) |
| Pregnancy | Generally considered acceptable at RDA doses; consult clinician | Insufficient data; not routinely recommended at supplemental doses |
| CAS | 14783-68-7 | 124-20-9 |
| PubChem CID | 84645 | 1102 |
| Wikidata | - | Q411089 |
Safety profile
Magnesium Glycinate
Common side effects
- mild GI upset at high doses
- loose stools (dose-dependent, less than with oxide/citrate forms)
Contraindications
- severe renal impairment
- myasthenia gravis
- heart block
Interactions
- tetracycline and fluoroquinolone antibiotics: magnesium chelates antibiotic, reducing absorption; separate by 2+ hours(moderate)
- bisphosphonates: reduced absorption of bisphosphonate(moderate)
- potassium-sparing diuretics: possible hypermagnesemia in renal impairment(moderate)
Spermidine
Common side effects
- mild GI upset (rare)
- headache (rare)
Contraindications
- wheat-germ allergy or celiac disease (for wheat-germ-extract products)
- active cancer (theoretical)
- pregnancy and lactation (insufficient data)
Interactions
- DFMO (difluoromethylornithine): competing polyamine metabolism; do not combine without oncology guidance(moderate)
Which Should You Take?
Magnesium Glycinate comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. Spermidine is the right call when one of the conditionals below applies.
- → If your priority is sleep onset or sleep quality, pick Magnesium Glycinate.
- → If your priority is post-training recovery, pick Magnesium Glycinate.
- → If your priority is healthspan extension, pick Spermidine.
- → If your priority is focus or working memory, pick Spermidine.
Default choice: Magnesium Glycinate. Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Spermidine 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 Glycinate and Spermidine?
Magnesium Glycinate and Spermidine differ in category (supplement vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Magnesium Glycinate or Spermidine?
Magnesium Glycinate half-life is 5 hours; Spermidine half-life is 6 hours.
Can you stack Magnesium Glycinate with Spermidine?
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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