Leung Leona Yuen-Ling, Tam Hon-Lon, Ho Jonathan Ka-Ming
School of Nursing and Health Sciences, Hong Kong Metropolitan University, Homantin, Kowloon, Hong Kong; Hong Kong Nutrition Association, Hong Kong; Independent Scholar, Ronin Institute, Hong Kong.
The Nethersole School of Nursing, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
Clin Nutr. 2025 Mar;46:10-18. doi: 10.1016/j.clnu.2025.01.017. Epub 2025 Jan 18.
More than one-third of individuals are overweight and obese in the world. Their risks of chronic health conditions are increased, which places additional burden on their family, caregivers, and healthcare system. Dietary modification is widely used for overweight and obese individuals. We investigated the effects of ketogenic diet (KD) and low-carbohydrate diet (LCD) in improving body weight (BW), body mass index (BMI), fat mass (FM), and body fat percentage (BFP) in overweight or obese individuals.
A three-step approach was adopted for searching relevant randomised controlled trials (RCTs) across five electronic databases. Two reviewers conducted the screening, review, and quality appraisal independently. A random-effects model was used because of variations in intervention and participant characteristics. Sensitivity and subgroup analyses were conducted to assess heterogeneity and variations in the results, respectively.
Thirty-three RCTs involving 2821 individuals were included. Overall meta-analysis results indicated that KD/LCD significantly reduced BW, BMI, and BFP, but not FM, in individuals with a carbohydrate intake of ≤100 g/d. Subgroup analyses revealed significant improvements in BW, BMI, and FM in individuals on KD/LCD for ≥1 month and in all parameters for those with a carbohydrate intake of ≤50 g/d. High statistical heterogeneity was noted because of variations in interventions and participant characteristics.
Adults with overweight or obesity should consume KD/LCD for ≥1 month and limit carbohydrate intake to ≤50 g/d. Further multicentre or multicountry RCTs are needed to improve the generalisability of our findings. We recommend integrating text messaging and evidence-based information to support interventions and ensuring stringent medical supervision throughout the intervention.
CRD42022353074.
全球超过三分之一的人超重或肥胖。他们患慢性健康疾病的风险增加，这给其家庭、照料者和医疗保健系统带来了额外负担。饮食调整广泛应用于超重和肥胖个体。我们研究了生酮饮食（KD）和低碳水化合物饮食（LCD）对超重或肥胖个体体重（BW）、体重指数（BMI）、脂肪量（FM）和体脂百分比（BFP）的改善效果。
采用三步法在五个电子数据库中检索相关随机对照试验（RCT）。两名评审员独立进行筛选、评审和质量评估。由于干预措施和参与者特征存在差异，使用随机效应模型。分别进行敏感性分析和亚组分析以评估结果的异质性和差异。
纳入了33项涉及2821名个体的RCT。总体荟萃分析结果表明，对于碳水化合物摄入量≤100克/天的个体，KD/LCD能显著降低BW、BMI和BFP，但对FM无显著影响。亚组分析显示，KD/LCD持续≥1个月的个体，其BW、BMI和FM有显著改善；碳水化合物摄入量≤50克/天的个体，所有参数均有改善。由于干预措施和参与者特征的差异，存在高度统计学异质性。
超重或肥胖的成年人应食用KD/LCD≥1个月，并将碳水化合物摄入量限制在≤50克/天。需要进一步开展多中心或多国RCT以提高我们研究结果的普遍性。我们建议整合短信和循证信息以支持干预措施，并在整个干预过程中确保严格的医学监督。
PROSPERO注册号：CRD42022353074。
