Efficacy and Safety of Time-Restricted Eating in Adults With Type 1 Diabetes: A Randomized Controlled Trial

Many adults with type 1 diabetes (T1D) have overweight or obesity, underscoring the need for effective dietary weight loss strategies in this population. Time-restricted eating (TRE) has emerged as a popular approach for weight loss; however, its efficacy and safety in T1D have not been evaluated. We examined whether TRE is more effective for reducing body weight than standard care (daily calorie restriction [CR]), or compared with a control group, in adults with T1D and overweight or obesity.

Participants were randomized to one of three groups for 6 months: 8-h TRE (eating only between 12:00 p.m. and 8:00 p.m., without calorie counting) versus CR (25% energy restriction daily), and compared with a no-intervention control group. The primary outcome was percent change in body weight by month 6.

Thirty-two participants were randomized. By month 6, body weight did not change significantly in the TRE group (-2.19% [95% CI -5.70, -1.31]) or CR group (-0.47% [95% CI -4.72, 3.78]) relative to a control group, or between TRE and CR groups (-1.73% [95% CI -5.37, 1.92]). HbA1c levels were significantly reduced by the TRE group when compared with the CR group (-0.46% [95% CI -0.80, -0.12]). There were no significant differences in total insulin dose or mean glucose levels across groups. TRE did not increase the risk for diabetic ketoacidosis, severe hypoglycemia, or severe hyperglycemia.

These findings suggest that TRE may be a safe approach for reducing HbA1c levels in T1D, although not more effective for weight loss compared with CR or a control group.