Leibel R L, Rosenbaum M, Hirsch J
Laboratory of Human Behavior and Metabolism, Rockefeller University, New York, NY 10021.
N Engl J Med. 1995 Mar 9;332(10):621-8. doi: 10.1056/NEJM199503093321001.
No current treatment for obesity reliably sustains weight loss, perhaps because compensatory metabolic processes resist the maintenance of the altered body weight. We examined the effects of experimental perturbations of body weight on energy expenditure to determine whether they lead to metabolic changes and whether obese subjects and those who have never been obese respond similarly.
We repeatedly measured 24-hour total energy expenditure, resting and nonresting energy expenditure, and the thermic effect of feeding in 18 obese subjects and 23 subjects who had never been obese. The subjects were studied at their usual body weight and after losing 10 to 20 percent of their body weight by underfeeding or gaining 10 percent by overfeeding.
Maintenance of a body weight at a level 10 percent or more below the initial weight was associated with a mean (+/- SD) reduction in total energy expenditure of 6 +/- 3 kcal per kilogram of fat-free mass per day in the subjects who had never been obese (P < 0.001) and 8 +/- 5 kcal per kilogram per day in the obese subjects (P < 0.001). Resting energy expenditure and nonresting energy expenditure each decreased 3 to 4 kcal per kilogram of fat-free mass per day in both groups of subjects. Maintenance of body weight at a level 10 percent above the usual weight was associated with an increase in total energy expenditure of 9 +/- 7 kcal per kilogram of fat-free mass per day in the subjects who had never been obese (P < 0.001) and 8 +/- 4 kcal per kilogram per day in the obese subjects (P < 0.001). The thermic effect of feeding and nonresting energy expenditure increased by approximately 1 to 2 and 8 to 9 kcal per kilogram of fat-free mass per day, respectively, after weight gain. These changes in energy expenditure were not related to the degree of adiposity or the sex of the subjects.
Maintenance of a reduced or elevated body weight is associated with compensatory changes in energy expenditure, which oppose the maintenance of a body weight that is different from the usual weight. These compensatory changes may account for the poor long-term efficacy of treatments for obesity.
目前尚无可靠的肥胖治疗方法能长久维持体重减轻，这可能是因为代偿性代谢过程会阻碍体重的维持。我们研究了体重的实验性改变对能量消耗的影响，以确定这些改变是否会导致代谢变化，以及肥胖受试者和从未肥胖的受试者反应是否相似。
我们对18名肥胖受试者和23名从未肥胖的受试者多次测量了24小时总能量消耗、静息和非静息能量消耗以及进食的热效应。这些受试者在其正常体重时接受研究，以及在通过限制饮食使体重减轻10%至20%或通过过度喂养使体重增加10%之后接受研究。
体重维持在比初始体重低10%或更多的水平时，从未肥胖的受试者的总能量消耗平均（±标准差）减少6±3千卡/千克去脂体重/天（P<0.001），肥胖受试者为8±5千卡/千克/天（P<0.001）。两组受试者的静息能量消耗和非静息能量消耗均减少3至4千卡/千克去脂体重/天。体重维持在比正常体重高10%的水平时，从未肥胖的受试者的总能量消耗增加9±7千卡/千克去脂体重/天（P<0.001），肥胖受试者为8±4千卡/千克/天（P<0.001）。体重增加后，进食的热效应和非静息能量消耗分别增加约1至2千卡/千克去脂体重/天和8至9千卡/千克去脂体重/天。这些能量消耗的变化与受试者的肥胖程度或性别无关。
体重降低或升高与能量消耗的代偿性变化有关，这些变化不利于维持与正常体重不同的体重。这些代偿性变化可能解释了肥胖治疗长期疗效不佳的原因。
