J Nutr. 2011 Feb;141(2):249-54. Epub 2010 Dec 15.

Higher branched-chain amino acid intake is associated with a lower prevalence of being overweight or obese in middle-aged East Asian and Western adults.

Qin LQ, Xun P, Bujnowski D, Daviglus ML, Van Horn L, Stamler J, He K; INTERMAP Cooperative Research Group.

Department of Nutrition, Gillings School of Global Public Health and School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.

Abstract

Beneficial effects on body weight of supplementation with BCAA, including leucine, isoleucine, and valine, have been observed in animal and human studies. However, population-based studies on dietary BCAA intake and body weight are lacking. The objective of this study was to examine the association between dietary BCAA intake and risk of overweight status/obesity among multi-ethnic populations. The International Study of Macro-/Micronutrients and Blood Pressure is a cross-sectional epidemiological investigation in China, Japan, the UK, and the US. The study cohort included 4429 men and women ages 40-59 y who were free of diabetes. Diet was assessed by 4 multi-pass 24-h recalls; data on nutrients including BCAA were derived from country-specific food tables. Overweight status and obesity were defined as BMI ≥ 25 and BMI ≥ 30 kg/m(2), respectively. Multivariable-adjusted OR of overweight status/obesity and 95% CI by quartiles of BCAA intake were estimated by logistic regression. Mean BCAA intake was 2.6 ± 0.6% energy; intake was significantly lower among Chinese participants and similar among participants from the other 3 countries. Compared with those in the first quartile, the multivariable-adjusted OR (95% CI) of overweight status from the 2nd to 4th quartiles of BCAA intake were 0.97 (0.80-1.17), 0.91 (0.75-1.11), and 0.70 (0.57-0.86), respectively (P-trend < 0.01). BCAA intake and obesity were also inversely associated (P-trend = 0.03). In conclusion, higher dietary BCAA intake is associated with lower prevalence of overweight status/obesity among apparently healthy middle-aged adults from East Asian and Western countries.