Research

Hormonal

Serum somatomedin-C (IGF-1) levels are highly sensitive to acute changes in nutritional status and correlate strongly with nitrogen balance, serving as a more responsive indicator of protein metabolism than total body nitrogen stores.

If you are monitoring your recovery from dieting or illness, serum IGF-1 (somatomedin-C) is a highly sensitive marker that reacts quickly to changes in your protein and energy intake. It changes much faster than your actual muscle mass or total body protein stores, making it a useful early warning system for nutritional deficits.

GoodSupportsHIGH confidence
The strong correlations among cumulative changes in somatomedin-C and cumulative changes in nitrogen balance during refeeding... provide further evidence that changes in somatomedin-C reflect changes in protein metabolism.
W L Isley et al. · Journal of Clinical Investigation · 1983

Why this rating

Strong statistical correlation (r=0.90) in a controlled setting.

Source

Dietary components that regulate serum somatomedin-C concentrations in humans.

W L Isley et al. · Journal of Clinical Investigation · 1983

DOI 10.1172/jci110757

crossover · n=5Cited 436×
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DOI resolved against Crossref · corpus check 2026-06-10

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