• 对164名超重或肥胖的成年人随机采用三种碳水化合物(CHO)供热比不同(分别为60%、40%、20%)的饮食,持续20周;
  • 在减重后的维持阶段,意向治疗分析中,与高CHO相比,中度CHO饮食组的总能量消耗平均增加91Kcal/d,低CHO组增加209 Kcal/d;
  • 符合方案分析中,该变化分别为131和278 Kcal/d;
  • 在减重前胰岛素分泌量最多的受试者中,不同饮食之间总能量消耗的差异更大;
  • 与高CHO饮食参与者相比,低CHO饮食者体内饥饿素和瘦素水平明显下降。
British Medical Journal上发表的一项最新研究,在164名超重/肥胖受试者中进行20周干预后发现,采用低碳水化合物饮食可增加能量消耗。

Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial



2018-11-14, Article

Abstract & Authors:展开

OBJECTIVE: To determine the effects of diets varying in carbohydrate to fat ratio on total energy expenditure.
DESIGN: Randomized trial.
SETTING: Multicenter collaboration at US two sites, August 2014 to May 2017.
PARTICIPANTS: 164 adults aged 18-65 years with a body mass index of 25 or more.
INTERVENTIONS: After 12% (within 2%) weight loss on a run-in diet, participants were randomly assigned to one of three test diets according to carbohydrate content (high, 60%, n=54; moderate, 40%, n=53; or low, 20%, n=57) for 20 weeks. Test diets were controlled for protein and were energy adjusted to maintain weight loss within 2 kg. To test for effect modification predicted by the carbohydrate-insulin model, the sample was divided into thirds of pre-weight loss insulin secretion (insulin concentration 30 minutes after oral glucose).
MAIN OUTCOME MEASURES: The primary outcome was total energy expenditure, measured with doubly labeled water, by intention-to-treat analysis. Per protocol analysis included participants who maintained target weight loss, potentially providing a more precise effect estimate. Secondary outcomes were resting energy expenditure, measures of physical activity, and levels of the metabolic hormones leptin and ghrelin.
RESULTS: Total energy expenditure differed by diet in the intention-to-treat analysis (n=162, P=0.002), with a linear trend of 52 kcal/d (95% confidence interval 23 to 82) for every 10% decrease in the contribution of carbohydrate to total energy intake (1 kcal=4.18 kJ=0.00418 MJ). Change in total energy expenditure was 91 kcal/d (95% confidence interval -29 to 210) greater in participants assigned to the moderate carbohydrate diet and 209 kcal/d (91 to 326) greater in those assigned to the low carbohydrate diet compared with the high carbohydrate diet. In the per protocol analysis (n=120, P<0.001), the respective differences were 131 kcal/d (-6 to 267) and 278 kcal/d (144 to 411). Among participants in the highest third of pre-weight loss insulin secretion, the difference between the low and high carbohydrate diet was 308 kcal/d in the intention-to-treat analysis and 478 kcal/d in the per protocol analysis (P<0.004). Ghrelin was significantly lower in participants assigned to the low carbohydrate diet compared with those assigned to the high carbohydrate diet (both analyses). Leptin was also significantly lower in participants assigned to the low carbohydrate diet (per protocol).
CONCLUSIONS: Consistent with the carbohydrate-insulin model, lowering dietary carbohydrate increased energy expenditure during weight loss maintenance. This metabolic effect may improve the success of obesity treatment, especially among those with high insulin secretion.

First Authors:
Cara B Ebbeling

Correspondence Authors:
David S Ludwig

All Authors:
Cara B Ebbeling,Henry A Feldman,Gloria L Klein,Julia M W Wong,Lisa Bielak,Sarah K Steltz,Patricia K Luoto,Robert R Wolfe,William W Wong,David S Ludwig