Department of Endocrinology and Metabolism, Zhujiang Hospital, Southern Medical University, No. 253, Industrial Avenue, Haizhu Square, Guangzhou, Guangdong, China.
Department of Bio-Statistics, Southern Medical University, No.1023 Sha Tai Nan Lu, Baiyun Square, Guangzhou, Guangdong, China.
BMC Med. 2023 May 24;21(1):192. doi: 10.1186/s12916-023-02869-9.
Both low-carbohydrate (LC) and calorie-restricted (CR) diets have been shown to have metabolic benefits. However, the two regimens have yet to be thoroughly compared. We conducted a 12-week randomized trial to compare the effects of these diets separately and in combination on both weight loss and metabolic risk factors in overweight/obese individuals.
A total of 302 participants were randomized to LC diet (n = 76), CR diet (n = 75), LC + CR diet (n = 76), or normal control (NC) diet (n = 75) using a computer-based random number generator. The primary outcome was the change in body mass index (BMI). The secondary outcomes included body weight, waist circumference, waist-to-hip ratio, body fat, and metabolic risk factors. All participants attended health education sessions during the trial.
A total of 298 participants were analyzed. BMI change over 12 weeks was - 0.6 (95% CI, - 0.8 to - 0.3) kg/m in NC, - 1.3 (95% CI, - 1.5 to - 1.1) kg/m in CR, - 2.3 (95% CI, - 2.6 to - 2.1) kg/m in LC, and - 2.9 (95% CI, - 3.2 to - 2.6) kg/m in LC + CR. LC + CR diet was more effective than LC or CR diet alone at reducing BMI (P = 0.001 and P < 0.001, respectively). Furthermore, compared with the CR diet, the LC + CR diet and LC diet further reduced body weight, waist circumference, and body fat. Serum triglycerides were significantly reduced in the LC + CR diet group compared with the LC or CR diet alone. Plasma glucose, homeostasis model assessment of insulin resistance, and cholesterol concentrations (total, LDL, and HDL) did not change significantly between the groups during the 12-week intervention.
The reduction of carbohydrate intake without restricting caloric intake is more potent to achieve weight loss over 12 weeks when compared to a calorie-restricted diet in overweight/obese adults. The combination of restricting carbohydrate and total calorie intake may augment the beneficial effects of reducing BMI, body weight, and metabolic risk factors among overweight/obese individuals.
The study was approved by the institutional review board of Zhujiang Hospital of Southern Medical University and registered at the China Clinical Trial Registration Center (registration number: ChiCTR1800015156).
低碳水化合物（LC）和热量限制（CR）饮食都已被证明具有代谢益处。然而，这两种方案尚未进行彻底比较。我们进行了一项为期 12 周的随机试验，以分别比较这两种饮食以及它们的组合对超重/肥胖个体的体重减轻和代谢风险因素的影响。
共有 302 名参与者使用基于计算机的随机数生成器随机分配至 LC 饮食组（n=76）、CR 饮食组（n=75）、LC+CR 饮食组（n=76）或正常对照组（n=75）。主要结局是体重指数（BMI）的变化。次要结局包括体重、腰围、腰臀比、体脂肪和代谢风险因素。所有参与者在试验期间均参加了健康教育课程。
共分析了 298 名参与者。NC 组 12 周 BMI 变化为-0.6（95%CI，-0.8 至-0.3）kg/m2，CR 组-1.3（95%CI，-1.5 至-1.1）kg/m2，LC 组-2.3（95%CI，-2.6 至-2.1）kg/m2，LC+CR 组-2.9（95%CI，-3.2 至-2.6）kg/m2。与 LC 或 CR 饮食相比，LC+CR 饮食在降低 BMI 方面更有效（P=0.001 和 P<0.001）。此外，与 CR 饮食相比，LC+CR 饮食和 LC 饮食进一步降低了体重、腰围和体脂肪。与 LC 或 CR 饮食相比，LC+CR 饮食组的血清三酰甘油显著降低。12 周干预期间，各组之间的血浆葡萄糖、胰岛素抵抗评估的稳态模型和胆固醇浓度（总胆固醇、LDL 和 HDL）均无明显变化。
与热量限制饮食相比，在超重/肥胖成年人中，12 周内减少碳水化合物摄入而不限制热量摄入更能有效减轻体重。限制碳水化合物和总热量摄入的组合可能会增强降低 BMI、体重和代谢风险因素的有益效果。
该研究获得了南方医科大学珠江医院机构审查委员会的批准，并在中国临床试验注册中心（注册号：ChiCTR1800015156）注册。
