Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
Khoo Teck Puat-National University Children's Medical Institute, National University Health System, Singapore.
J Nutr. 2021 Apr 8;151(4):911-920. doi: 10.1093/jn/nxaa414.
Branched-chain amino acid (BCAA) supplementation has been shown to increase muscle mass or prevent muscle loss during weight loss.
We aimed to investigate the effects of a BCAA-supplemented hypocaloric diet on lean mass preservation and insulin sensitivity.
A total of 132 Chinese adults (63 men and 69 women aged 21-45 y, BMI 25-36 kg/m2) were block randomly assigned by gender and BMI into 3 hypocaloric diet (deficit of 500 kcal/d) groups: standard-protein (14%) with placebo (control, CT) or BCAA supplements at 0.1 g · kg-1 body weight · d-1 (BCAA) or high-protein (27%) with placebo (HP). The subjects underwent 16 wk of dietary intervention with provision of meals and supplements, followed by 8 wk of weight maintenance with provision of supplements only. One-way ANOVA analysis was conducted to analyze the primary (lean mass and insulin sensitivity) and secondary outcomes (anthropometric and metabolic parameters) among the 3 groups. Paired t-test was used to analyze the change in each group.
The 3 groups demonstrated similar significant reductions in body weight (7.97%), fat mass (13.8%), and waist circumference (7.27%) after 16 wk of energy deficit. Lean mass loss in BCAA (4.39%) tended to be lower than in CT (5.39%) and higher compared with HP (3.67%) (P = 0.06). Calf muscle volume increased 3.4% in BCAA and intramyocellular lipids (IMCLs) decreased in BCAA (17%) and HP (18%) (P < 0.05) over 16 wk. During the 8 wk weight maintenance period, lean mass gain in BCAA (1.03%) tended to be lower compared with CT (1.58%) and higher than in HP (-0.002%) (P = 0.04). Lean mass gain differed significantly between CT and HP (P = 0.03). Insulin sensitivity and metabolic profiles did not differ among the groups throughout the study period.
BCAA supplementation does not preserve lean mass or affect insulin sensitivity in overweight and obese adults during weight loss. A higher protein diet may be more advantageous for lean mass preservation.
支链氨基酸（BCAA）补充已被证明可在减肥过程中增加肌肉量或防止肌肉流失。
我们旨在研究补充 BCAA 的低热量饮食对瘦体重保留和胰岛素敏感性的影响。
共有 132 名中国成年人（63 名男性和 69 名女性，年龄 21-45 岁，BMI 25-36 kg/m2）按性别和 BMI 分为 3 个低热量饮食（热量减少 500 kcal/d）组：标准蛋白（14%）安慰剂（对照，CT）或 BCAA 补充剂 0.1 g·kg-1·d-1（BCAA）或高蛋白（27%）安慰剂（HP）。受试者接受了 16 周的饮食干预，提供膳食和补充剂，然后仅提供补充剂进行 8 周的体重维持。采用单因素方差分析比较 3 组间的主要（瘦体重和胰岛素敏感性）和次要结局（人体测量和代谢参数）。采用配对 t 检验分析每组的变化。
3 组在 16 周的能量不足后体重（7.97%）、脂肪量（13.8%）和腰围（7.27%）均显著降低。BCAA（4.39%）的瘦体重损失趋势低于 CT（5.39%），高于 HP（3.67%）（P=0.06）。BCAA 组小腿肌肉体积增加 3.4%，BCAA 和 HP 组肌内甘油三酯（IMCL）分别减少 17%和 18%（P<0.05）。在 8 周的体重维持期间，BCAA（1.03%）的瘦体重增加趋势低于 CT（1.58%），高于 HP（-0.002%）（P=0.04）。CT 和 HP 之间的瘦体重增加有显著差异（P=0.03）。胰岛素敏感性和代谢特征在整个研究期间在各组之间没有差异。
在减肥期间，BCAA 补充不能保留瘦体重或影响超重和肥胖成年人的胰岛素敏感性。高蛋白饮食可能更有利于保留瘦体重。
