Research

Hormonal

Genetic variants in the IGF-IR and PI3KCB genes that result in lower free plasma IGF-I levels are associated with increased human longevity, specifically in individuals aged 85 and older.

This research suggests that longevity is linked to specific genetic variants that naturally keep IGF-I levels lower. There is no direct intervention protocol here, but it implies that maintaining metabolic health and avoiding excessive IGF-I elevation (e.g., through excessive caloric intake or supplementation) might align with natural longevity pathways. Focus on healthy aging rather than maximizing hormone levels.

ModerateSupportsMEDIUM confidence
The major finding of this investigation was that subjects carrying at least an A allele at IGF-IR have low levels of free plasma IGF-I and are more represented among long-lived people.
Massimiliano Bonafè et al. · The Journal of Clinical Endocrinology & Metabolism · 2003

Why this rating

Observational cross-sectional study with a specific, carefully selected population (healthy >85yo), but lacks longitudinal follow-up and causal proof in humans.

Source

Polymorphic Variants of Insulin-Like Growth Factor I (IGF-I) Receptor and Phosphoinositide 3-Kinase Genes Affect IGF-I Plasma Levels and Human Longevity: Cues for an Evolutionarily Conserved Mechanism of Life Span Control

Massimiliano Bonafè et al. · The Journal of Clinical Endocrinology & Metabolism · 2003

DOI 10.1210/jc.2002-021810

cross_sectional · n=496Cited 314×
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DOI resolved against Crossref · corpus check 2026-06-10

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