Cancer Prevention Laboratory, Colorado State University, 1173 Campus Delivery, Fort Collins, CO 80523, USA.
Cancer Prev Res (Phila). 2011 Nov;4(11):1736-42. doi: 10.1158/1940-6207.CAPR-11-0133. Epub 2011 Oct 7.
Overweight and obese individuals frequently restrict caloric intake to lose weight. The resultant weight loss, however, typically is followed by an equal or greater weight gain, a phenomenon called weight cycling. Most attention to weight cycling has focused on identifying its detrimental effects, but preclinical experiments indicating that intermittent caloric restriction or fasting can reduce cancer risk have raised interest in potential benefits of weight cycling. Although hypothesized adverse effects of weight cycling on energy metabolism remain largely unsubstantiated, there is also a lack of epidemiologic evidence that intentional weight loss followed by regain of weight affects chronic-disease risk. In the limited studies of weight cycling and cancer, no independent effect on postmenopausal breast cancer but a modest enhancement of risk for renal cell carcinoma, endometrial cancer, and non-Hodgkin's lymphoma have been reported. An effect of either intermittent caloric restriction or fasting in protecting against cancer is not supported by the majority of rodent carcinogenesis experiments. Collectively, the data argue against weight cycling and indicate that the objective of energy balance-based approaches to reduce cancer risk should be to strive to prevent adult weight gain and maintain body weight within the normal range defined by body mass index.
超重和肥胖的个体经常限制热量摄入以减肥。然而，由此导致的体重减轻通常会伴随着同等或更大的体重增加，这种现象称为体重循环。大多数关于体重循环的关注都集中在确定其有害影响上，但临床前实验表明，间歇性热量限制或禁食可以降低癌症风险，这引起了人们对体重循环潜在益处的兴趣。尽管体重循环对能量代谢的假设不利影响在很大程度上仍未得到证实，但也缺乏流行病学证据表明，有意减肥后体重恢复会影响慢性病风险。在对体重循环和癌症的有限研究中，尚未报道体重循环对绝经后乳腺癌有独立影响，但据报道，体重循环对肾细胞癌、子宫内膜癌和非霍奇金淋巴瘤的风险有适度增加。大多数啮齿动物致癌实验都不支持间歇性热量限制或禁食对癌症的保护作用。总的来说，这些数据反对体重循环，并表明基于能量平衡的方法来降低癌症风险的目标应该是努力预防成人体重增加，并将体重维持在由体重指数定义的正常范围内。
