BMJ Open Diabetes Research and Care Researchers examined data from 23,475 people who took part in the National Health and Nutrition Examination Survey (51% men, ages 20 to 80). Participants reported how long they typically slept on weekdays and weekends. Researchers then estimated their insulin sensitivity - how efficiently cells respond to insulin and absorb sugar from the bloodstream - using a measure called estimated glucose disposal rate. This value is calculated from a formula using waist