Earlier Sleep Schedule May Help Improve Weight Loss Outcomes in Prediabetes: Study

Could going to bed earlier help you lose weight, even without sleeping longer? A new clinical trial suggests that earlier bedtimes may be associated with greater weight loss among adults with prediabetes, highlighting the potential importance of sleep timing in metabolic health.

Published in the journal Nursing Research, the randomised controlled trial conducted by researchers at New York University's Rory Meyers College of Nursing investigated whether improving sleep habits alongside lifestyle changes could support weight loss and blood sugar regulation.

Researchers enrolled 196 adults aged 21 to 64 years who had prediabetes and regularly slept fewer than 6.5 hours per night.

Participants were randomly assigned to two groups for an eight-week diabetes prevention programme.

Both groups received guidance on healthy eating, physical activity and stress management. However, one group also received additional sleep coaching designed to improve sleep habits and gradually encourage earlier bedtimes.

The findings revealed that participants in both groups experienced improvements in sleep and reductions in body weight.

Importantly, those receiving additional sleep coaching reported greater improvements in sleep quality and daytime sleepiness compared with participants receiving standard lifestyle guidance alone.

Researchers also found that across all participants, every one-hour earlier shift in sleep onset was associated with approximately 0.6 kilograms, or 1.3 pounds, of weight loss over eight weeks.

Interestingly, this association remained even after accounting for total sleep duration, suggesting that when people fall asleep may be relevant to weight management independently of how long they sleep.

Researchers suggested that earlier bedtimes could help reduce late-night eating and better align eating habits with the body's natural metabolic rhythms.

However, neither intervention produced measurable improvements in blood glucose levels during the study period.

The trial also did not establish that shifting bedtime earlier directly caused weight loss, hence, longer studies are needed to confirm its clinical benefits.

REFERENCE: Malone, S. K., Patterson, F., Hu, J., Goyal, C., & Melkus, G. D. (2026). Randomized Controlled Trial of Lifestyle Plus Sleep Extension Intervention on Adults With Prediabetes and Short SleepNursing Research https://doi.org/10.1097/NNR.0000000000000957