Siervo Mario, Faber Peter, Lara Jose, Gibney Eileen R, Milne Eric, Ritz Patrick, Lobley Gerald E, Elia Marinos, Stubbs R James, Johnstone Alexandra M
Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Campus for Ageing and Vitality, Newcastle on Tyne, NE4 5PL, UK.
Rowett Institute of Nutrition and Health, University of Aberdeen, Greenburn Road, Bucksburn, Aberdeen, AB21 9SB, UK.
Metabolism. 2015 Aug;64(8):896-904. doi: 10.1016/j.metabol.2015.03.011. Epub 2015 Apr 8.
Weight loss (WL) is associated with a decrease in total and resting energy expenditure (EE). We aimed to investigate whether (1) diets with different rate and extent of WL determined different changes in total and resting EE and if (2) they influenced the level of adaptive thermogenesis, defined as the decline in total or resting EE not accounted by changes in body composition.
Three groups of six, obese men participated in a total fast for 6 days to achieve a 5% WL and a very low calorie (VLCD, 2.5 MJ/day) for 3 weeks or a low calorie (LCD, 5.2 MJ/day) diet for 6 weeks to achieve a 10% WL. A four-component model was used to measure body composition. Indirect calorimetry was used to measure resting EE. Total EE was measured by doubly labelled water (VLCD, LCD) and 24-hour whole-body calorimetry (fasting).
VLCD and LCD showed a similar degree of metabolic adaptation for total EE (VLCD = -6.2%; LCD = -6.8%). Metabolic adaptation for resting EE was greater in the LCD (-0.4 MJ/day, -5.3%) compared to the VLCD (-0.1 MJ/day, -1.4%) group. Resting EE did not decrease after short-term fasting and no evidence of adaptive thermogenesis (+0.4 MJ/day) was found after 5% WL. The rate of WL was inversely associated with changes in resting EE (n = 30, r = 0.-42, p=0.01).
The rate of WL did not appear to influence the decline in total EE in obese men after 10% WL. Approximately 6% of this decline in total EE was explained by mechanisms of adaptive thermogenesis.
体重减轻（WL）与总能量消耗和静息能量消耗（EE）的减少有关。我们旨在研究：（1）不同体重减轻速率和程度的饮食是否会导致总能量消耗和静息能量消耗产生不同变化；以及（2）它们是否会影响适应性产热水平，适应性产热定义为总能量消耗或静息能量消耗的下降，且这种下降不能用身体成分的变化来解释。
三组，每组六名肥胖男性参与研究，一组进行6天的完全禁食以实现5%的体重减轻，一组采用极低热量饮食（VLCD，2.5兆焦耳/天）持续3周，另一组采用低热量饮食（LCD，5.2兆焦耳/天）持续6周以实现10%的体重减轻。使用四成分模型测量身体成分。采用间接测热法测量静息能量消耗。总能量消耗通过双标水法（VLCD、LCD组）和24小时全身量热法（禁食组）进行测量。
VLCD组和LCD组在总能量消耗方面表现出相似程度的代谢适应（VLCD组=-6.2%；LCD组=-6.8%）。与VLCD组（-0.1兆焦耳/天，-1.4%）相比，LCD组（-0.4兆焦耳/天，-5.3%）静息能量消耗的代谢适应更大。短期禁食后静息能量消耗并未降低，体重减轻5%后未发现适应性产热的证据（+0.4兆焦耳/天）。体重减轻速率与静息能量消耗的变化呈负相关（n = 30，r = -0.42，p = 0.01）。
体重减轻速率似乎并未影响肥胖男性体重减轻10%后总能量消耗的下降。总能量消耗下降的约6%可由适应性产热机制来解释。
