Wyatt H R, Grunwald G K, Seagle H M, Klem M L, McGuire M T, Wing R R, Hill J O
Center for Human Nutrition, University of Colorado Health Sciences Center, Denver 80262, USA.
Am J Clin Nutr. 1999 Jun;69(6):1189-93. doi: 10.1093/ajcn/69.6.1189.
Weight loss in obese subjects is associated with a reduction in resting metabolic rate (RMR). Whether the reduction can be explained solely by a reduction in lean body mass remains controversial.
Our objective was to determine whether the reduction in RMR after weight loss was proportional to the decrease in lean mass alone or was greater than could be explained by body composition.
We measured the RMR, fasting respiratory quotient (RQ), and body composition in 40 reduced-obese subjects [ie, 7 men and 33 women who had lost > or = 13.6 kg (30 lb) and maintained the loss for > or = 1 y] enrolled in the National Weight Control Registry and 46 weight-matched control subjects (9 men, 37 women).
A stepwise multiple regression found lean mass, fat mass, age, and sex to be the best predictors of RMR in both groups. After adjusting RMR for these variables, we found no significant difference in RMR (5926 +/- 106 and 6015 +/- 104 kJ/d) between the 2 groups (P = 0.35). When we adjusted fasting RQ for percentage body fat and age, the reduced-obese group had a slightly higher (0.807 +/- 0.006) RQ than the control group (0.791 +/- 0.005, P = 0.05). This may have been due to the consumption of a diet lower in fat or to a reduced capacity for fat oxidation in the reduced-obese group.
These results show that in at least some reduced-obese individuals there does not seem to be a permanent obligatory reduction in RMR beyond the expected reduction for a reduced lean mass.
肥胖受试者体重减轻与静息代谢率（RMR）降低有关。静息代谢率的降低是否仅由去脂体重的减少来解释仍存在争议。
我们的目的是确定体重减轻后静息代谢率的降低是否仅与去脂体重的减少成正比，还是大于身体成分变化所能解释的程度。
我们测量了40名体重减轻的肥胖受试者（即7名男性和33名女性，体重减轻≥13.6 kg（30磅）且体重维持减轻状态≥1年）和46名体重匹配的对照受试者（9名男性，37名女性）的静息代谢率、空腹呼吸商（RQ）和身体成分，这些体重减轻的肥胖受试者均登记在国家体重控制登记处。
逐步多元回归分析发现，去脂体重、脂肪量、年龄和性别是两组静息代谢率的最佳预测因素。在对这些变量进行静息代谢率校正后，我们发现两组之间的静息代谢率无显著差异（分别为5926±106和6015±104 kJ/d，P = 0.35）。当我们对空腹呼吸商进行体脂百分比和年龄校正后，体重减轻的肥胖组呼吸商（0.807±0.006）略高于对照组（0.791±0.005，P = 0.05）。这可能是由于体重减轻的肥胖组食用了脂肪含量较低的饮食，或者是脂肪氧化能力降低所致。
这些结果表明，至少在一些体重减轻的肥胖个体中，静息代谢率似乎没有出现超出因去脂体重减少而预期降低的永久性必然降低。
