Nature communicationsNov 19, 2025

Timing and effects of life-extending treatments vary across early, middle, and late life

Longevity & Aging Weekly Brief ↗PubMed ↗DOI ↗OA ↗

Updated Jun 27, 2026

Abstract

Essence

Temporal efficacy profiling suggests many mouse lifespan interventions have age-limited, sometimes harmful effects rather than uniform benefits.

Evidence

This analytical study applied a new age-specific mortality method to NIA Interventions Testing Program survival data for 42 mouse-tested compounds, finding 22 with age-specific mortality reductions, 15 with age-specific increases, and 8 with late-life reductions.

Caveat

The findings depend on reanalysis of mouse compound-screen survival data and show timing of mortality risk, not mechanisms or human anti-aging efficacy.

Simplified

A growing number of compounds are reported to extend lifespan, but it remains unclear whether they reduce mortality across the entire life course or only at specific ages. This uncertainty persists because the commonly used log-rank test cannot detect age-specific effects. Here, we introduce a new analytical method that addresses this limitation by revealing when, how long, and to what extent interventions alter mortality risk. Applied to survival data from 42 compounds tested in mice by the National Institute on Aging Interventions Testing Program, it identified 22 that reduced mortality at certain ages, more than detected by the log-rank test, while 15 increased mortality at certain ages. Most compounds were effective only within restricted age ranges; just 8 reduced mortality late in life, when burdens of aging are greatest. Compared to conventional methods, this approach uncovers more beneficial and harmful effects, offers deeper insight into timing and mechanism, and can guide development of future anti-aging therapies.