Abstract：
Animal studies showed a detrimental effect of dietary branched chain amino acids (BCAAs) on metabolic health, while epidemiological evidence on dietary BCAAs and obesity is limited and inconclusive. We hypothesized that high dietary and circulating BCAAs are unfavorably associated with obesity in community-dwelling adults. We evaluated the 1-year longitudinal associations of dietary BCAA intake and circulating BCAAs with body fat measures. Body weight, height, and circumferences of the waist (WC) and hip (HC) were measured at baseline and again after 1-year. Body composition and liver fat [indicated by controlled attenuation parameter (CAP)] were also assessed after 1-year. Serum BCAA concentrations at baseline were quantified by liquid chromatography mass spectrometry. Diet was collected using 4 quarterly 3-day recalls during the 1-year. The correlation coefficients between dietary and serum BCAAs were 0.12 (P = .035) for total dietary BCAAs, and ranged from -0.02 (soy foods, P = .749) to 0.18 (poultry, P = .001). Total dietary BCAA intake was associated with increase in body weight (β = 0.044, P = .022) and body mass index (BMI, β = 0.047, P = .043). BCAAs from animal foods were associated with increase in HC, while BCAAs from soy foods were associated with weight gain and higher CAP (all P < .05). Serum BCAAs were associated with higher WC, HC, BMI, body fat mass, visceral fat level, and CAP (all P < .05). These results support that dietary and circulating BCAAs are positively associated with the risk of obesity. More cohort studies with validated dietary assessment tools and long-term follow-up among diverse populations are needed to confirm our findings.
摘要：
动物研究表明，膳食支链氨基酸（BCAAs）对代谢健康的有害影响，而关于饮食BCAAs和肥胖的流行病学证据有限且尚无定论。我们假设，在社区居住的成年人中，高饮食和循环的BCAA与肥胖不利相关。我们评估了膳食BCAA摄入量和循环BCAA与体脂指标的1年纵向关联。体重,高度,在基线和1年后再次测量腰围（WC）和臀围（HC）。还在1年后评估身体成分和肝脏脂肪[由受控衰减参数(CAP)指示]。通过液相色谱质谱法定量基线时的血清BCAA浓度。在1年内使用4个季度的3天召回收集饮食。膳食和血清BCAAs的相关系数为0.12(P=.035)。范围从-0.02(大豆食品，P=.749)至0.18(家禽，P=.001)。总的膳食BCAA摄入量与体重（β=0.044，P=0.022）和体重指数（BMI，β=0.047，P=.043）。动物性食物中的BCAA与HC的增加有关，而大豆食品中的BCAA与体重增加和较高的CAP相关（所有P<0.05）。血清BCAA与较高WC相关，HC,BMI,身体脂肪量,内脏脂肪水平,和CAP（所有P<0.05）。这些结果支持饮食和循环BCAA与肥胖风险正相关。需要更多的队列研究，使用经过验证的饮食评估工具，并在不同人群中进行长期随访，以证实我们的发现。
