Research

Macro partitioning

High protein-to-carbohydrate (P:C) ratios shorten lifespan in insects, potentially via TOR pathway activation, while low P:C ratios extend lifespan via AMPK activation, unless obesity ensues.

In insects, high protein shortens life via TOR, and low protein extends life via AMPK, but too little protein causes obesity. For humans, this implies a 'Goldilocks' zone for protein: too high may accelerate aging, too low may cause obesity, and the optimal balance is likely species-specific.

ModerateQualifiesMEDIUM confidence
Factors that directly or indirectly increase TOR signaling... are broadly anabolic and life-shortening. In contrast low levels of nutrients... and other influences that stimulate AMPK signaling are catabolic and life-extending... except when overconsumption, obesity and insulin resistance are driven by protein shortage on a habitually low percent protein diet.
Stephen J. Simpson et al. · Aging · 2009

Why this rating

Mechanistic evidence is strong in insects, but the application to mammals is presented as a prediction/hypothesis.

Source

Macronutrient balance and lifespan

Stephen J. Simpson et al. · Aging · 2009

DOI 10.18632/aging.100098

narrative_reviewCited 179×
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DOI resolved against Crossref · corpus check 2026-06-10

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