Background: Recent evidence has related high levels of plasma branch-chained amino acids (BCAAs) with liver and visceral fat. We examined the associations of plasma BCAAs with liver fat and abdominal fat distribution and assessed the potential modification of weight-loss diet interventions on these relations.
Methods: The current study included 184 participants with available data on plasma BCAAs, hepatic fat and abdominal fat distribution over 2 years, who were randomly assigned to 1 of 4 diets varying in macronutrient components.
Results: Decrease in plasma BCAAs after weight loss was significantly associated with improvement in hepatic density (a marker for hepatic fat; p=0.03) and reduction in visceral fat (p=0.01). We also found that a decrease in BCAAs was associated with decreased insulin, HOMA-IR, and triglycerides (p<0.05 for all). Moreover, we observed significant interactions between total plasma BCAAs and dietary protein on hepatic density (p-interaction=0.01). Individuals with a larger decrease in total BCAAs had a greater increase in hepatic density when consuming a high protein diet.
Conclusion: Our findings indicate that weight-loss diets decrease BCAAs, which are in turn associated with the reduction of hepatic and visceral fat. Finally, dietary protein modifies the direction of these associations.
X. Li: None. D. Sun: None. T. Zhou: None. G. Bray: Advisory Panel; Self; Herbalife International of America, Inc., Medifast. F. Sacks: None. L. Qi: None.
National Heart, Lung, and Blood Institute (HL0791981, HL034594, HL126024); National Institute of Diabetes and Digestive and Kidney Diseases (DK115679, DK091718, DK100383, DK078616); Boston Nutrition Obesity Research Center (DK46300); United States-Israel Binational Science Foundation (2011036); American Heart Association (0730094N to L.Q.)