BACKGROUND: Type 2 diabetes (T2D) is a progressive disease driven by insulin resistance and β-cell dysfunction, often exacerbated by excess body weight. Intermittent fasting (IF) approaches, including intermittent energy restriction (IER) and time-restricted eating (TRE), have shown promise for improving glycemic control and facilitating diabetes remission. However, the feasibility and effectiveness of these IF approaches in individuals with T2D remain underexplored.
OBJECTIVE: This study aims to compare the feasibility, acceptability, and metabolic effects of IER and TRE in a randomized parallel trial in adults with T2D.
METHODS: Adults with T2D (N = 56) and overweight/obesity will be randomized to one of two interventions: IER (550-800 kcal/day on 2-3 days/week) or TRE (caloric intake within an 8-h daily window). Both groups will receive a comprehensive, remotely delivered diabetes education and behavioral support program over 6 months, followed by a 6-month low-contact follow-up during which participants continued the intervention on their own. Primary outcomes include feasibility (recruitment, retention, adherence) and acceptability. Secondary outcomes include changes in HbA1c, insulin sensitivity, insulin response to a mixed-meal tolerance test, body composition, and diabetes remission. Continuous glucose monitoring, metabolic and behavioral phenotyping will inform predictors of response.
CONCLUSION: This study is the first parallel trial to compare IER and TRE in patients with T2D and overweight/obesity. Results will provide critical data on the metabolic and behavioral responses to each IF approach, informing future strategies to personalize nutrition therapy in T2D.
