Did extending sleep duration change insulin sensitivity in people with overweight?
A small but well-designed trial directly tested whether getting more sleep improves insulin sensitivity in people with overweight or obesity who habitually sleep less than 7 hours per night. The answer is no: extending sleep by about 1 hour per night for roughly 6 weeks improved sleep health but did not change how the body responds to insulin 5. This suggests that sleep extension alone may not be enough to reverse insulin resistance in this population, though other aspects of sleep health did improve.
What the research says
In a randomized controlled trial, 29 adults with overweight or obesity, insulin resistance, and habitual short sleep (less than 7 hours per night) were assigned to either extend their sleep or keep their usual sleep schedule for about 6 weeks 5. The extended sleep group increased time in bed by about 1.3 hours per night and actual sleep duration by about 1.1 hours per night, while the control group had minimal changes 5. Despite these gains, measures of whole-body, liver, and fat tissue insulin sensitivity (measured by the gold-standard hyperinsulinemic-euglycemic clamp) did not differ between groups, nor did 24-hour blood sugar control 5. The study did find improvements in day-to-day sleep consistency and subjective sleep quality in the extension group 5. These results indicate that while sleep extension can improve sleep health, it does not necessarily translate into better metabolic outcomes in the short term. Other research in people with overweight has explored different ways to improve metabolic health, such as dietary changes or exercise timing, but these are separate interventions 46.
What to ask your doctor
- Could my sleep habits be affecting my insulin sensitivity or blood sugar control?
- Are there other lifestyle changes (like diet or exercise timing) that might help improve my insulin sensitivity more than sleep extension alone?
- Should I consider a sleep study if I have trouble sleeping or suspect a sleep disorder?
- How can I best track my sleep quality and duration to discuss with you at my next visit?
This question is drawn from common patient questions about Diabetes & Endocrinology and answered using cited medical research. We do not provide individualized advice.