Division of Physiology, Department of Medicine, University of Fribourg, Fribourg, Switzerland.
Int J Obes (Lond). 2006 Dec;30 Suppl 4:S58-66. doi: 10.1038/sj.ijo.0803520.
In people trying to lose weight, there are often repeated cycles of weight loss and regain. Weight cycling is, however, not limited to obese adults but affects people of normal weight, particularly young women, who are unhappy with their appearance. Furthermore, the onset of a pattern of weight cycling is shifting towards younger ages, owing to the increasing prevalence of overweight and obesity in children and adolescents, and the pressure from the media and society for a slim image even for normal weight children. Although there is still controversy whether weight cycling promotes body fat accumulation and obesity, there is mounting evidence from large population studies for increased cardiovascular risks in response to a behavior of weight cycling. Potential mechanisms by which weight cycling contributes to cardiovascular morbidity include hypertension, visceral fat accumulation, changes in adipose tissue fatty acid composition, insulin resistance and dyslipidemia. Moreover, fluctuations in blood pressure, heart rate, sympathetic activity, glomerular filtration rate, blood glucose and lipids that may occur during weight cycling--with overshoots above normal values during weight regain periods--put an additional load on the cardiovascular system, and may be easily overlooked if humans or animals are studied during a state of relatively stable weight. Overshoot of those risks factors, when repeated over time, will stress the cardiovascular system and probably contribute to the overall cardiovascular morbidity of weight cycling.
在试图减肥的人群中，体重往往会反复减轻和反弹。体重反弹不仅限于肥胖成年人，还会影响到体重正常的人群，尤其是对自己的外表不满意的年轻女性。此外，由于超重和肥胖在儿童和青少年中的普遍流行，以及媒体和社会对苗条形象的压力，即使对于正常体重的儿童也是如此，体重反弹模式的出现年龄也在逐渐提前。尽管关于体重反弹是否会促进体脂肪积累和肥胖仍存在争议，但大量人群研究的证据表明，体重反弹的行为会增加心血管风险。体重反弹导致心血管发病率的潜在机制包括高血压、内脏脂肪堆积、脂肪组织脂肪酸组成的变化、胰岛素抵抗和血脂异常。此外，体重反弹期间可能会出现血压、心率、交感神经活动、肾小球滤过率、血糖和血脂的波动，在体重恢复期间会超过正常水平，这会给心血管系统带来额外的负担，如果在相对稳定的体重状态下对人类或动物进行研究，可能很容易被忽视。这些危险因素的过度反应，如果随着时间的推移反复出现，将给心血管系统带来压力，可能导致体重反弹的整体心血管发病率升高。
