A 5:2 Intermittent Fasting Meal Replacement Diet and Glycemic Control for Adults With Diabetes: The EARLY Randomized Clinical Trial.

Importance: An intermittent fasting plan consisting of 2 nonconsecutive fasting days and 5 days of habitual intake per week and meal replacement diet (5:2 MR) could provide additional benefits to patients with type 2 diabetes. Objective: To evaluate the effect of the 5:2 MR on glycemic control among patients with early type 2 diabetes compared with metformin and empagliflozin. Design, Setting, and Participants: The EARLY (Exploration of Treatment of Newly Diagnosed Overweight/Obese Type 2 Diabetes Mellitus) study is a randomized, open-label, active parallel-controlled clinical trial conducted between November 13, 2020, and December 29, 2022, in 9 centers across China. A total of 509 eligible patients underwent screening, out of which 405 were randomly assigned to 3 groups and included in the intention-to-treat analysis. Interventions: Patients were randomly allocated in a 1:1:1 ratio to receive either metformin, empagliflozin, or 5:2 MR. The treatment was 16 weeks, with an 8-week follow-up. Main Outcomes and Measures: The primary end point was the change in hemoglobin A1c (HbA1c) level from baseline to 16 weeks. Secondary end points included changes in body weight, anthropometric measurements, and biochemical parameters. Results: Of the 405 randomized participants (265 men [65.4%]; mean [SD] age, 45.5 [11.0] years; mean [SD] body mass index, 29.5 [4.1]; and mean [SD] HbA1c level, 7.9% [0.6%]), 332 completed the 16-week treatment. From baseline to week 16, participants in the 5:2 MR group showed the greatest reduction in HbA1c (least-squares mean [LSM], -1.9% [SE, 0.2%]), significantly greater than patients receiving metformin (LSM, -1.6% [SE, 0.2%]; adjusted LSM difference, -0.3% [95% CI, -0.4% to -0.1%]) and empagliflozin (LSM, -1.5% [SE, 0.2%]; adjusted LSM difference, -0.4% [95% CI, -0.6% to -0.2%]). At week 16, the mean weight loss in the 5:2 MR group (LSM, -9.7 kg [SE, 2.2 kg]) was greater than that in the metformin group (LSM, -5.5 kg [SE, 2.3 kg]) and empagliflozin group (LSM, -5.8 kg [SE, 2.3 kg]). Conclusions and Relevance: This randomized clinical trial of Chinese adults with overweight or obesity and with early type 2 diabetes found that 5:2 MR could improve glycemic outcomes and weight loss in the short term compared with metformin or empagliflozin, making it a promising initial intervention and early management for type 2 diabetes. Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR2000040656.