Scientists have identified what may be the optimal amount of sleep for reducing the risk of insulin resistance, a precursor to type 2 diabetes. An analysis of data from over 23,000 US adults suggests that seven hours and 18 minutes of sleep per night is the sweet spot. Those who slept less than this duration typically had lower estimated glucose disposal rate (eGDR) scores, indicating higher insulin resistance and greater diabetes risk.
The research, published in BMJ Open Diabetes Research and Care, also examined the effects of weekend catch-up sleep. The team from China found that while topping up sleep at the weekend was beneficial for those with weekday sleep debt, it could be detrimental for those who already slept sufficiently. The authors advocate for personalised sleep guidelines that encourage consistent, adequate sleep rather than relying on weekend compensation.
Professor Naveed Sattar, an expert in cardiometabolic medicine at the University of Glasgow, urged caution in interpreting the findings, noting that the study was observational and could not prove causation. He highlighted existing evidence linking short sleep—typically less than seven hours—with higher type 2 diabetes risk, explaining that poor sleep disrupts appetite hormones and increases opportunities to eat.
Professor Sattar emphasised the importance of good sleep hygiene, including consistent bedtimes, wind-down routines, and reducing screen use before bed. He added that digital distractions may be contributing to declining sleep quality and duration, which could in turn fuel obesity and diabetes.
