Research

Hormonal

Elevated plasma concentrations of branched-chain amino acids (BCAAs), specifically leucine and valine, are strongly correlated with worsening glucose homeostasis (HbA1c) and insulin resistance in obese individuals, reflecting impaired amino acid catabolism and TCA cycle inefficiency.

If you are obese and have insulin resistance, high blood levels of BCAAs (leucine, valine) are a marker of metabolic stress, not just dietary intake. Focus on improving insulin sensitivity through lifestyle changes rather than simply restricting protein, as your body may be struggling to metabolize these amino acids efficiently.

GoodSupportsHIGH confidence
Leucine and valine concentrations rose with increasing HbA1c, and significantly correlated with plasma acetylcarnitine concentrations. It is hypothesized that this reflects a close link between abnormalities in glucose homeostasis, amino acid catabolism, and efficiency of fuel combustion in the tricarboxylic acid (TCA) cycle.
Oliver Fiehn et al. · PLoS ONE · 2010

Why this rating

Observational metabolomic study with strong statistical correlations (p<0.0001) in a well-defined cohort, but causality is not definitively proven.

Source

Plasma Metabolomic Profiles Reflective of Glucose Homeostasis in Non-Diabetic and Type 2 Diabetic Obese African-American Women

Oliver Fiehn et al. · PLoS ONE · 2010

DOI 10.1371/journal.pone.0015234

cross_sectional · n=56Cited 431×
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DOI resolved against Crossref · corpus check 2026-06-10

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