Plasma Amino Acids as Correlates of Serum Insulin-Like Growth Factor 1, Linear Growth, and Fat-Free Mass: A Cross-Sectional Study among Ugandan Children with Stunting.
Level 4 - case-series / case-control
Cross-sectional observational study nested within a trial
PubMed 42002262 · doi:10.1016/j.tjnut.2026.101543
What was done
A cross-sectional study nested within a nutrition intervention trial assessed 750 stunted Ugandan children aged 12–59 months (mean age 32.0 months, mean height-for-age z-score -3.02). Investigators evaluated anthropometry, body composition (fat-free mass [FFM] and FFM index), fasting time, and 24-hour intake of animal-source foods (ASFs). Laboratory measurements included serum IGF-1, inflammatory markers (C-reactive protein and α1-acid glycoprotein), and 21 plasma amino acids (AAs, available in 711–730 children). Adjusted associations were examined between plasma AAs and serum IGF-1, linear growth (HAZ), and FFM.
What was found
Plasma concentrations of 18 AAs were lower among children with elevated inflammatory markers. Recent ASF intake showed limited relationships: meat intake was associated with higher plasma methionine, but cow milk and egg intake were not associated with any essential amino acid (EAA) levels. After adjustment for fasting duration and inflammation markers, nearly all plasma AAs, including all EAAs, were positively associated with serum IGF-1. In contrast, only a few AAs (methionine, threonine, valine) were associated with FFM or FFM index, and only tyrosine and taurine were associated with HAZ. Specific effect sizes, confidence intervals, and p-values were not reported in the abstract.
Why it matters
This study links circulating amino acid profiles to the systemic growth factor IGF-1 in undernourished children, helping clarify metabolic disruptions in pediatric stunting.
Limits
The cross-sectional design cannot establish causality or temporal direction between amino acid levels, IGF-1, and linear growth faltering. The abstract does not report numerical effect sizes or confidence intervals. The study was restricted to stunted children aged 12–59 months in Uganda, limiting generalizability to well-nourished populations or other age groups. Dietary intake was limited to a 24-hour recall of animal-source foods.
Cited by
- context Methionine has been shown to be the most active amino acid in driving the IGF-1 pathway.