Sleeping for 7 hours and 18 minutes every night may be the sweet spot for warding off the risk of insulin resistance—the precursor to type 2 diabetes—suggests a large observational study published in the open access journal BMJ Open Diabetes Research & Care.
But weekend catch-up sleep is associated with a heightened risk of impaired glucose metabolism in those who sleep beyond the optimal threshold every night, the findings indicate.
Previously published research shows that sleep duration is strongly associated with the risk of insulin resistance, diabetes, and related metabolic disorders, note the researchers. But it’s not entirely clear what role weekend catch-up sleep might have, if any.
Estimated glucose disposal rate (eGDR) is considered a reliable surrogate for insulin resistance, they explain. The lower the eGDR (less than 6–7 mg/kg/min, for example) the greater the risk of insulin resistance; the higher the eGDR (more than 10 mg/kg/min, for example), the lower the risk.
The researchers therefore wanted to investigate the association between weekday sleep duration and eGDR and any moderating effect of weekend catch-up sleep, with a view to informing clinical practice for people with diabetes.
They included 23,475 participants, aged 20 to 80, from serial waves of the National Health and Nutrition Examination Survey (NHANES) between 2009 and 2023 in their analysis: 10,817 of them had available data on weekend sleep duration.
Weekend catch-up sleep was categorised as none; up to 1 hour; 1 to 2; and more than 2. The eGDR was calculated using a formula involving waist circumference, fasting blood glucose, and blood pressure.
The average eGDR among participants was 8.23, and on weekdays, they slept for an average of 7 hours and 30 minutes. Just over 48% of them reported catch-up sleep at the weekend. Those with weekend sleep data slept for an average of 8 hours at the weekend.
Analysis of the data revealed an inverted U shaped curve between sleep duration and eGDR, with a sweet spot of 7 hours and 18 minutes.
Below this threshold, getting more nightly sleep was associated with higher eGDR; above it, more nightly sleep was associated with a lower eGDR, particularly among women and those between the ages of 40 and 59.
Further statistical analysis showed that for those sleeping less than the optimal threshold during the week, 1–2 hours of weekend catch-up sleep was associated with higher eGDR compared with none.
But for those sleeping more than the optimal weekday sleep threshold, more than 2 hours of weekend catch-up sleep was associated with a lower eGDR after accounting for potentially influential factors, such as lifestyle, ethnicity, marital status, and educational attainment.
“Importantly, there appears to be a bidirectional relationship between sleep and metabolism. For instance, poor glycemic status itself has been linked to a higher likelihood of both short and extended sleep durations, as well as sleep disorders,” explain the researchers.
“This creates a potential vicious cycle wherein metabolic dysregulation disrupts normal sleep patterns, and the resultant abnormal sleep (including extended duration) further aggravates metabolic health.”
This is an observational study, and as such, no firm conclusions can be drawn about cause and effect. And the researchers acknowledge that the study relied on self-reported data on sleep duration, and they couldn’t rule out reverse causation whereby disrupted glucose metabolism may interfere with sleep rather than the other way round.
But they conclude: “These correlational findings suggest that sleep patterns, particularly weekend recovery sleep, may be relevant for metabolic regulation in diabetes and could inform considerations for healthcare professionals in managing patient care.”
BMJ Open Diabetes Research & Care
Observational study
People
Association of weekday sleep duration and estimated glucose disposal rate: the role of weekend catch- up sleep
3-Mar-2026