Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20133Milan, Italy.
Department of Medicine, Università degli Studi di Udine, 33100Udine, Italy.
Br J Nutr. 2021 Jul 14;126(1):22-27. doi: 10.1017/S0007114520003724. Epub 2020 Sep 23.
An adequate intake of branched-chain amino acids (BCAA) is required for protein synthesis and metabolic functions, including insulin metabolism. Emerging studies found positive associations between BCAA and the risk of various diseases sharing aetiological aspects with colorectal cancer (CRC), including type 2 diabetes, obesity and pancreatic cancer. We investigated the relation between dietary BCAA and CRC using data from a multicentric Italian case-control study, including 1953 cases of CRC (of these, 442 of sigmoid colon) and 4154 hospital controls with acute, non-neoplastic diseases. A validated FFQ was used to estimate the participants' usual diet and to assess dietary intakes of various nutrients, including energy, BCAA and Ca. OR and corresponding CI were computed by multiple logistic regression models adjusted for age, sex and other confounding factors, including total energy intake. BCAA intake was inversely related to CRC risk (OR for the highest v. the lowest quintile 0·73; 95 % CI 0·55, 0·97), but the association was attenuated after adjustment for Ca intake (OR 0·90; 95 % CI 0·65, 1·25). An inverse association with sigmoid colon cancer risk also remained after adjustment for other dietary factors, including Ca intake (OR 0·49; 95 % CI 0·27, 0·87). This study provides supporting evidence that higher levels of dietary BCAA intake are not associated with an increase of CRC risk, but confirms that they may be related to a reduced risk of sigmoid colon cancer.
支链氨基酸（BCAA）的充足摄入对于蛋白质合成和代谢功能是必需的，包括胰岛素代谢。新出现的研究发现，BCAA 与各种具有结直肠癌（CRC）病因学方面相似的疾病（包括 2 型糖尿病、肥胖和胰腺癌）的风险之间存在正相关关系。我们使用来自意大利多中心病例对照研究的数据来研究膳食 BCAA 与 CRC 之间的关系，该研究包括 1953 例 CRC（其中 442 例为乙状结肠癌）和 4154 例患有急性非肿瘤性疾病的医院对照者。使用经过验证的 FFQ 来估计参与者的常规饮食，并评估各种营养素（包括能量、BCAA 和钙）的饮食摄入量。通过多因素逻辑回归模型计算 OR 和相应的 CI，该模型调整了年龄、性别和其他混杂因素，包括总能量摄入。BCAA 摄入量与 CRC 风险呈负相关（最高五分位组与最低五分位组的 OR 为 0.73；95%CI 为 0.55，0.97），但调整钙摄入量后，这种关联减弱（OR 为 0.90；95%CI 为 0.65，1.25）。在调整其他饮食因素，包括钙摄入量后，与乙状结肠癌风险的负相关关系仍然存在（OR 为 0.49；95%CI 为 0.27，0.87）。本研究提供了支持性证据，表明较高水平的膳食 BCAA 摄入与 CRC 风险的增加无关，但证实它们可能与乙状结肠癌风险的降低有关。
