Lai C, Dunn D M, Miller M F, Pence B C
Department of Animal Science and Food Technology, Texas Tech University, Lubbock 79409, USA.
Cancer Lett. 1997 Jan 15;112(1):87-91. doi: 10.1016/S0304-3835(96)04549-1.
Significant alarm has existed among the general public in the past few years that eating red meat may cause human colon cancer. Iron in beef has been hypothesized as one of the factors in the etiology of this cancer. The present study was designed to test the hypothesis that dietary iron solely from beef would enhance colon tumorigenesis induced in rats. Tumors were induced in Sprague-Dawley rats with 1,2-dimethylhydrazine (20 mg/kg body weight for 10 weeks). Seventy male weanling rats were randomized to two dietary treatment groups with two iron sources (very lean beef vs. iron citrate) as the factor. The rats were allowed free access to the respective diet and deionized water for 27 weeks. At termination of the study, the rats were examined for location, size and type of colon or extracolonic lesions. No significant differences were found in total incidence and number of colon tumors between the beef (51.7%, 0.8 tumors/rat) and casein (62.1%, 0.9 tumors/rat) diets, although the serum iron levels of rats fed the beef diet were higher than for those fed the casein diet. The results demonstrate that, when lean beef is used as an iron source, the risk for colon carcinogenesis is not increased.
在过去几年中，普通大众一直存在着严重的担忧，即食用红肉可能会导致人类患结肠癌。牛肉中的铁被认为是这种癌症病因中的因素之一。本研究旨在验证以下假设：仅来自牛肉的膳食铁会增强大鼠结肠癌的发生。用1,2-二甲基肼（20毫克/千克体重，持续10周）在斯普拉格-道利大鼠中诱发肿瘤。70只雄性断奶大鼠被随机分为两个饮食治疗组，以两种铁源（极瘦牛肉与柠檬酸铁）作为因素。大鼠可自由获取各自的饮食和去离子水，持续27周。在研究结束时，检查大鼠结肠或结肠外病变的位置、大小和类型。牛肉组（51.7%，0.8个肿瘤/只大鼠）和酪蛋白组（62.1%，0.9个肿瘤/只大鼠）之间的结肠肿瘤总发生率和数量没有显著差异，尽管喂食牛肉饮食的大鼠血清铁水平高于喂食酪蛋白饮食的大鼠。结果表明，当使用瘦牛肉作为铁源时，结肠癌发生的风险不会增加。
