Klurfeld D M, Welch C B, Lloyd L M, Kritchevsky D
Wistar Institute of Anatomy and Biology, Philadelphia, PA 19104.
Int J Cancer. 1989 May 15;43(5):922-5. doi: 10.1002/ijc.2910430532.
Most previous studies on the inhibiting effect of caloric restriction during promotion of DMBA-induced mammary carcinogenesis have used low to moderate levels of dietary fat, i.e., about 4 to 14% by weight. The current study was designed to test whether a moderate degree of caloric restriction, 25%, would inhibit tumor growth in rats fed the equivalent of 20% dietary fat which approximates human consumption in affluent countries. Rats were fed diets ad libitum that contained 5, 15 or 20% corn oil. Groups of rats were pair-fed to the last 2 groups, but subjected to a 25% caloric restriction. These groups were fed 20 or 26.7% corn oil so that absolute fat intake in the paired groups was identical. Significant inhibition of tumor incidence, tumor weight, tumor burden, body fat deposition, and fasting serum insulin were observed in the 2 calorically restricted groups. We conclude that moderate caloric restriction is significantly more effective in inhibiting tumor growth than is the promoting effect of diets high in fat. Total body weight, body fat and serum insulin concentrations may be better correlates of risk of developing mammary tumors than is dietary fat.
此前大多数关于热量限制对二甲基苯并蒽（DMBA）诱导的乳腺癌发生促进阶段抑制作用的研究，使用的膳食脂肪水平较低至中等，即按重量计约4%至14%。当前研究旨在测试25%的适度热量限制是否会抑制喂食相当于20%膳食脂肪（接近富裕国家人类摄入量）的大鼠的肿瘤生长。大鼠随意进食含有5%、15%或20%玉米油的饲料。将几组大鼠与后两组进行配对喂食，但进行25%的热量限制。这些组喂食20%或26.7%的玉米油，以使配对组的绝对脂肪摄入量相同。在两个热量限制组中观察到肿瘤发生率、肿瘤重量、肿瘤负荷、体脂沉积和空腹血清胰岛素受到显著抑制。我们得出结论，适度热量限制在抑制肿瘤生长方面比高脂肪饮食的促进作用显著更有效。总体重、体脂和血清胰岛素浓度可能比膳食脂肪更能较好地反映发生乳腺肿瘤的风险。
