Serum branch chain amino acids and aromatic amino acids ratio and metabolic risks in Koreans with normal-weight or obesity: a cross-sectional study.

Objectives: Metabolic disease is strongly associated with future insulin resistance, and its prevalence is increasing worldwide. Thus, identifying early biomarkers of metabolic-related disease based on serum profiling is useful to control future metabolic disease. Our study aimed to assess the association of serum branched chain amino acids (BCAAs) and aromatic amino acids (AAAs) ratio and metabolic disease according to body mass index (BMI) status among Korean adults. Methods: This cross-sectional study included 78 adults aged 20-59 years in Korea. We compared serum amino acid (AA) levels between adults with normal-weight and adults with obesity and investigated biomarkers of metabolic disease. We examined serum AA levels, blood profile, and body composition. We also evaluated the association between serum AAs and metabolic-related disease. Results: The height, weight, BMI, waist circumference, hip circumference, waist-hip-ratio, body fat mass, body fat percent, skeletal muscle mass, systolic blood pressure, and diastolic blood pressure were higher in the group with obesity compared to normal weight group. The group with obesity showed significantly higher levels of BCAA, AAA, and BCAA and AAA ratio. Further, BCAA and AAA ratio were significantly positively correlated with triglyceride, body weight, and skeletal muscle mass. The evaluation of metabolic disease risks revealed an association between the ratios of BCAAs and AAAs, hypertension, and metabolic syndrome. Conclusions: Our study is showed the associations between BCAA and AAA ratio, obesity, and obesity-related diseases using various analytical approaches. The elevated BCAA and AAA ratio could be early biomarkers for predicting future metabolic diseases in Korean population.