Tier 1 — highest

Spermidine for cognitive ageing: insights into observational and interventional studies

Lirong Yu, Bin Li, Na Li, Kaisy Xinhong Ye, Kai Xuan Lim, Anderson Li Yang Khoo, Bingxue Han, Guohua Lu, Mei Song, Wei Ma, Brian Keith Kennedy, Andrea Britta Maier, Lei Feng

General Psychiatry 2025 38(5):e101723

Bibliography

PubMed: PMID 41098596
PubMed Central: PMC12519323
DOI: 10.1136/gpsych-2024-101723
Competing interests: None declared.

Study snapshot

Design	Evidence review of observational and interventional studies
Model	Human cognitive-aging literature with mechanistic context
Sample	Not applicable — review
Intervention	Not applicable; evidence synthesis
Duration	Not applicable — review
Endpoints	Cognition; Dementia risk; Dietary exposure; Supplementation; Biomarkers

What the study showed, in plain terms

This 2025 synthesis is one of the most useful high-level resources for reconciling promising dietary associations with mixed supplementation trials in cognitive aging.

Key findings

Human cognitive evidence is heterogeneous: observational dietary studies are often favorable, while intervention studies vary by dose, population and endpoint and include the null primary outcome in SmartAge.

What this study can and cannot tell us

Underlying human studies remain heterogeneous and often small, with different exposure definitions, formulations and cognitive outcomes. Synthesis cannot eliminate those limitations.

Editorial review

Reviewed by the Biohack Blueprint research team

Khaled Mahmoud