Research
Macro partitioning
In humans, severe calorie restriction does not reduce serum IGF-1 levels unless protein intake is also reduced, whereas in rodents, CR reduces IGF-1 without protein restriction.
If you are practicing calorie restriction and want to potentially lower IGF-1 (which may reduce cancer risk), consider moderately reducing your protein intake to around 0.75 g/kg body weight, rather than consuming high amounts of protein. This is a nuanced strategy that differs from standard fitness advice.
GoodQualifiesHIGH confidence
In contrast, in humans, severe CR does not reduce serum IGF-1 and IGF-1/IGFBP-3 concentrations, unless protein intake is also reduced [42].
Why this rating
Based on specific human studies comparing CR with high vs. low protein intake.
Source
Calorie restriction and prevention of age‐associated chronic disease
Daniela Omodei et al. · FEBS Letters · 2011
DOI 10.1016/j.febslet.2011.03.015
narrative_reviewCited 290×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Calorie restriction (CR) without malnutrition prevents or delays age-associated chronic diseases, including abdominal obesity, type 2 diabetes, hypertension, and cardiovascular diseases, in both non-human primates and humans.Good
- Calorie restriction reduces oxidative damage to macromolecules (DNA, proteins, lipids) and down-regulates the insulin/IGF-1/mTOR signaling pathways, which are key mechanisms for extending healthspan and lifespan.Moderate
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