Research

Hormonal

Reducing brain-specific IGF-1 receptor signaling lowers somatotropic hormone output (GH/IGF-I), which extends mean lifespan and delays mortality in mammals.

This research suggests that lower levels of Growth Hormone and IGF-1 signaling are associated with a longer life in mammals. While this is a genetic study in mice, it challenges the common practice of using GH to combat aging in humans, implying that high levels of these hormones might carry a risk of shortened lifespan.

StrongSupportsHIGH confidence
Partial inactivation of IGF-1R in the embryonic brain selectively inhibited GH and IGF-I pathways after birth... led to delayed mortality and longer mean lifespan.
Laurent Kappeler et al. · PLoS Biology · 2008

Why this rating

Controlled conditional mutagenesis in mice with clear phenotypic and survival data.

Source

Brain IGF-1 Receptors Control Mammalian Growth and Lifespan through a Neuroendocrine Mechanism

Laurent Kappeler et al. · PLoS Biology · 2008

DOI 10.1371/journal.pbio.0060254

mechanism_only · n=138Cited 288×
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DOI resolved against Crossref · corpus check 2026-06-10

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