Reviewed by Nabus Research · last reviewed 2026-07-11 · about our review process

Human lifespan evidence: none

Classification

Intervention class: Naturally occurring polyamine; autophagy-associated dietary compound

Aliases: Wheat germ extract (dietary source form -- NOT dose-equivalent, see datamodel warning)

Relationship to mTOR: Proposed to induce autophagy substantially through mTOR-independent mechanisms (e.g., EP300/p300 acetyltransferase inhibition) rather than acting as a direct mTOR kinase inhibitor like rapamycin. It is grouped in this dataset for evidence-map comparability, not because it shares rapamycin's mechanism.

Mechanism summary: Associated with induction of autophagic flux and cardiovascular protection in animal models; proposed mechanisms include EP300 inhibition and polyamine-pathway effects. See /mtorc1-vs-mtorc2 for the broader autophagy-pathway reference.

Regulatory status

Sold as a dietary/food-derived compound and supplement (commonly as wheat germ extract); no drug approval; no established longevity dose in any regulatory framework.

Evidence per species / population (5-qualifier claim format)

Mouse (drinking water) Tier 6 · Single-lab animal lifespan verification: verified_2026-07-11

1. Species / populationMouse, standard drinking-water supplementation studies

2. Exposure, route, schedule~3 mM spermidine in drinking water

3. Comparator & durationUntreated/control drinking water; lifespan follow-up

4. Endpoint & numeric resultReported cardiovascular benefit and ~+10% median lifespan extension, described in the brief as sex-specific (not uniform across both sexes)

5. What this study did NOT establishDoes not establish the effect in humans, at dietary intakes, or at wheat-germ-extract-equivalent doses (unit conversion is not established -- see datamodel warning).

Rat (drinking water) Tier 6 · Single-lab animal lifespan verification: verified_2026-07-11

1. Species / populationRat, drinking-water supplementation studies

2. Exposure, route, schedule~3 mM spermidine in drinking water (same nominal concentration as the mouse studies above)

3. Comparator & durationUntreated/control drinking water; lifespan follow-up

4. Endpoint & numeric resultDid NOT reproduce the mouse lifespan-extension effect at the equivalent nominal concentration

5. What this study did NOT establishThis is a negative/non-replicating finding at the species level and is deliberately kept in the SAME evidence table as the positive mouse result, not split into a separate 'limitations' page, per editorial policy.

Negative / null / conflicting findings

Rat drinking-water studies did not reproduce the mouse lifespan effect at ~3 mM. verification: verified_2026-07-11

SmartAge RCT (human, 12 months, 0.9 mg/day via wheat germ extract): primary cognitive endpoint difference -0.03 (95% CI -0.11 to 0.05), p=.47 -- no significant effect. [study record] verification: verified_2026-07-11

Safety

Safety notes

As a dietary/food-derived compound with no drug approval, there is no regulatory drug label to cite. General tolerability data at supplement doses is not compiled in this proof-of-concept dataset; this field should not be read as an assertion of safety.

Source: (not applicable (no drug label)) verification: verified_2026-07-11

Editorial policy: This site publishes no dosing calculator and no acquisition guidance for spermidine.

Data model warning: mg spermidine (as pure compound) is NOT the same quantity as mg wheat-germ-extract, mg from dietary intake, or mM in drinking water. These exposure units are stored separately per study and must never be silently converted or summed.

Funding / conflict of interest

Funding sources and conflict-of-interest disclosures for individual studies are not reproduced here pending primary-source verification; see each linked study record.

The form used in the studies

A product-fact block, not a recommendation. It records the form the studies used and what they administered. mTORiX does not rank products, name a best one, suggest a dose, or claim an effect.

Regulatory status

Sold as a dietary/food-derived compound and supplement (commonly as wheat germ extract); no drug approval; no established longevity dose in any regulatory framework.

Before you buy: mg spermidine (as pure compound) is NOT the same quantity as mg wheat-germ-extract, mg from dietary intake, or mM in drinking water. These exposure units are stored separately per study and must never be silently converted or summed.

Find Spermidine on Amazon →

The search returns several variants. The studies used Spermidine. The animal studies used spermidine in drinking water; supplement products are commonly wheat germ extract, which is not dose-equivalent to the material used in those studies.

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Related study records

Version 0.1.0-poc · literature search date 2026-07-11 · editorial owner Nabus Research