Study record
SmartAge trial (spermidine via wheat germ extract, 12-month RCT)
Primary: cognitive composite score change
Human — Older adults enrolled in the SmartAge RCT Tier 2 · Human clinical/functional RCT verification: verified
1. Species / populationOlder adult humans, SmartAge RCT, n=100
2. Exposure, route, schedule0.9 mg/day spermidine equivalent via wheat germ extract, oral, daily
3. Comparator & durationPlacebo, 12 months
4. Endpoint & numeric resultPrimary cognitive composite: difference -0.03 (95% CI -0.11 to 0.05), p=.47 -- no effect
5. What this study did NOT establishNo lifespan data; no significant cognitive effect at tested dose/duration; no cross-unit conversion to animal drinking-water doses
Full record
| Intervention(s) | Spermidine |
| Species | Human |
| Population | Older adults enrolled in the SmartAge RCT |
| Sample size | 100 participants verification: verified_2026-07-11 |
| Exposure | 0.9 mg/day spermidine (via wheat germ extract) — Daily oral dosing verification: verified_2026-07-11 |
| Comparator | Placebo |
| Duration | 12 months |
| Endpoint | Primary: cognitive composite score change |
| Evidence tier | Tier 2 · Human clinical/functional RCT |
| What was NOT established | Did not test lifespan. No significant cognitive benefit found at this dose/duration/formulation. Does not establish effects of higher doses, pure-compound dosing, or the mM-in-drinking-water exposures used in the mouse/rat studies on the spermidine intervention page -- unit conversion between mg wheat-germ-extract and mM drinking water is NOT established. |
Result values (as reported in sourcing brief)
| primary endpoint difference | -0.03 |
| confidence interval 95 | -0.11 to 0.05 |
| p value | p = .47 |
| interpretation | No significant effect |
| verification | verification: verified_2026-07-11 |
Source citation
Verification status: verified This record was checked against its primary publication on 2026-07-11.Identifiers: PMID verified; DOI verified; PMC verified; trial registry ID not reported. Record-level verification and identifier-level status are separate: a record can be fully verified against its primary publication while an identifier that does not apply to the study type — a trial registry ID for an animal study, for instance — is marked not applicable. No identifier is fabricated, and none is left in a “pending” state.
| trial name | SmartAge |
| pmid | 35616942 verified |
| doi | 10.1001/jamanetworkopen.2022.13875 verified |
| journal | JAMA Network Open 2022 |
| trial registry id | not reported not reported |
| pmc | PMC9136623 verified |
| authors | Schwarz C, Benson GS, Horn N, et al. (SmartAge) |
| year | 2022 |
| verified date | 2026-07-11 |
| verified note | n=100, 60-90 yo SCD, 0.9 mg/d wheat-germ spermidine vs placebo, 12 mo; primary mnemonic-discrimination NOT significantly improved — MATCHES (null result confirmed). |
| verification status | verified |
Funding / conflict of interest
not compiled in this proof-of-concept verification: verified_2026-07-11
Version 0.1.0-poc · literature search date 2026-07-11 · editorial owner Nabus Research