Am J Epidemiol. 2013 Oct 15;178(8):1226-32. doi: 10.1093/aje/kwt112. Epub 2013 Sep 5.
Dietary supplementation with branched-chain amino acids (BCAAs), including leucine, isoleucine, and valine, has shown potential benefits for the metabolic profile. However, higher blood BCAA levels have been associated with insulin resistance. To our knowledge, there has been no study on dietary BCAAs and the risk of diabetes. We examined the association between BCAA intake and risk of diabetes in a population-based cohort study in Japan. A total of 13,525 residents of Takayama City, Japan, who enrolled in a cohort study in 1992 responded to a follow-up questionnaire seeking information about diabetes in 2002. Diet at baseline was assessed by means of a validated food frequency questionnaire. A high intake of BCAAs in terms of percentage of total protein was significantly associated with a decreased risk of diabetes in women after controlling for covariates; the hazard ratio for the highest tertile versus the lowest was 0.57 (95% confidence interval: 0.36, 0.90; P-trend = 0.02). In men, leucine intake was significantly marginally associated with the risk of diabetes; the hazard ratio for the highest tertile versus the lowest was 0.70 (95% confidence interval: 0.48, 1.02; P-trend = 0.06). Data suggest that a high intake of BCAAs may be associated with a decrease in the risk of diabetes.
饮食补充支链氨基酸（BCAA），包括亮氨酸、异亮氨酸和缬氨酸，已显示出对代谢谱的潜在益处。然而，较高的血液 BCAA 水平与胰岛素抵抗有关。据我们所知，目前还没有关于饮食 BCAA 和糖尿病风险的研究。我们在日本的一项基于人群的队列研究中检查了 BCAA 摄入与糖尿病风险之间的关联。日本高山市的 13525 名居民参加了 1992 年的一项队列研究，他们在 2002 年回复了一份关于糖尿病的随访问卷。通过验证过的食物频率问卷评估了基线时的饮食。在控制了混杂因素后，高蛋白质中 BCAA 的高摄入量与女性糖尿病风险降低显著相关；最高三分位组与最低三分位组的风险比为 0.57（95%置信区间：0.36，0.90；P 趋势=0.02）。在男性中，亮氨酸摄入量与糖尿病风险呈显著边缘相关；最高三分位组与最低三分位组的风险比为 0.70（95%置信区间：0.48，1.02；P 趋势=0.06）。数据表明，高 BCAA 摄入可能与降低糖尿病风险有关。
