Seven Hours of Sleep Linked to Lower Insulin Resistance Risk: Study Shows

A large observational study suggests that sleeping about 7 hours and 18 minutes per night may be the optimal duration for reducing the risk of insulin resistance, a condition that often precedes Type 2 Diabetes. The research, published in the journal BMJ Open Diabetes Research & Care, also found that excessive weekend “catch-up sleep” may negatively affect glucose metabolism in some individuals.

Researchers analyzed data from 23,475 adults aged 20 to 80 who participated in the National Health and Nutrition Examination Survey (NHANES) between 2009 and 2023. Among them, 10,817 participants had additional information about their weekend sleep patterns. The team evaluated sleep duration and its relationship with insulin resistance using a measurement called the estimated glucose disposal rate. Lower eGDR values indicate greater insulin resistance, while higher values suggest healthier glucose metabolism.

On average, participants slept 7 hours and 30 minutes on weekdays and about 8 hours on weekends. Nearly 48% reported catching up on sleep during weekends. When researchers analyzed the data, they discovered an inverted U-shaped relationship between sleep duration and metabolic health. The highest eGDR—indicating the lowest risk of insulin resistance—occurred at around 7 hours and 18 minutes of sleep per night.

For people who slept less than this optimal amount on weekdays, getting 1–2 hours of additional sleep on weekends was linked to better metabolic outcomes and higher eGDR. However, for individuals who already slept more than the optimal amount during the week, adding more than 2 hours of weekend catch-up sleep was associated with lower eGDR, meaning a higher risk of insulin resistance. This effect appeared particularly strong among women and adults aged 40 to 59.

Researchers note that sleep and metabolism influence each other. Poor glucose regulation can disrupt sleep patterns, while abnormal sleep durations may further worsen metabolic health. Although the study cannot prove cause and effect, the findings suggest that maintaining consistent sleep patterns close to seven hours per night may help support healthy metabolism and reduce diabetes risk.

REFERENCE: Fan, Z., et al. (2026) Association of weekday sleep duration and estimated glucose disposal rate: the role of weekend catch-up sleep. BMJ Open Diabetes Research & Care. DOI: 10.1136/bmjdrc-2025-005692. https://drc.bmj.com/content/14/2/e005692