Circadian-Based Program to Improve Insulin Sensitivity and Sleep in Adults with Overweight or Obesity

What this Trial Is About

Researchers are evaluating a circadian intervention aimed at improving insulin sensitivity and sleep among adults aged 18 to 45 with overweight or obesity who habitually sleep less than 6.5 hours per night. This randomized controlled trial compares a circadian intervention group with a control group receiving general health information. The study focuses on cardiometabolic health and lifestyle factors related to sleep hygiene, eating habits, and time-restricted feeding. Participants in the circadian intervention group receive counseling to reduce evening and nighttime light exposure, increase exposure to morning light, and complete all food intake at least four hours before bedtime. The control group receives general health advice about diet, physical activity, and goal setting. Both groups have similar contact time with the study team. The study includes an 1-week baseline monitoring phase, followed by an 8-week experimental segment where participants follow their assigned intervention or control routine. Throughout the study, sleep duration is tracked using a wrist device and daily sleep logs. Participants complete overnight laboratory visits at the end of baseline and experimental segments to assess insulin sensitivity through an oral glucose tolerance test and circadian timing via dim light melatonin onset. The primary outcome is the change in insulin sensitivity after the 8-week intervention. Secondary outcomes include changes in circadian timing, plasma ceramides, sleep duration and satisfaction, food intake timing, and alertness. The total participation spans approximately 9 weeks, including baseline and experimental phases.

Circadian Intervention to Improve Cardiometabolic Health