Scientists have discovered the perfect length of time to sleep to reduce the risk of developing insulin resistance, which can lead to type 2 diabetes.
Diabetes UK said that of the 4.6 million people in the UK who have a diabetes diagnosis, about 90 per cent have type 2 diabetes, which occurs when the body does not use insulin properly.
Obesity and high blood pressure are known causes of the condition, but a lack of sleep has also been linked to insulin resistance.
Sleeping for seven hours and 18 minutes every night may be the sweet spot, with any more or less sleep associated with a heightened risk of pre-diabetes, a study published in the journal BMJ Open Diabetes Research & Care revealed.
Naveed Sattar, professor of cardiometabolic medicine at the University of Glasgow, told The Independent: “Poor sleep often leads to poorer appetite control so people tend to eat more, and less sleep means more time awake to be able to eat.”
He explained that poor sleep can have a direct impact on hormone levels, such as stress hormones, which not only make people eat more but also impact sugar levels.
Alex Miras, professor of endocrinology at Ulster University, told The Independent: “Sleep deprivation has been known for years to be associated with higher levels of body stress, meaning that the body produces excess cortisol and other molecules that have a negative effect on glucose regulation. More specifically, it can increase the resistance of muscles to insulin, which can increase blood glucose.”
For the study, researchers in China wanted to investigate the association between how much sleep participants got on a weekday and weekend and their estimated glucose disposal rate (eGDR), a marker of insulin resistance which can indicate diabetes. The lower the eGDR level, the greater the insulin resistance.
Data from 10,817 participants aged 20 to 80 from the National Health and Nutrition Examination Survey in the US between 2009 and 2023 were included in the analysis.
The eGDR was calculated using a formula involving waist circumference, fasting blood glucose, and blood pressure.
Participants slept for an average of seven hours and 30 minutes. Just over 48 per cent of them reported catching up on sleep at the weekend and getting up to eight hours a night.
After analysing participants’ eGDR levels, researchers found the optimal sleep duration for insulin resistance was suggested to be seven hours and 18 minutes, with anything higher or lower associated with worse results.
Getting extra sleep on the weekend in moderation was also beneficial for insulin resistance.
For those sleeping less than the optimal amount during the week, one to two hours of catch-up sleep at the weekend was associated with higher eGDR compared with no extra sleep at the weekend, lowering their risk of type 2 diabetes.
But for those sleeping more than the optimal weekday threshold, more than two hours of extra sleep at the weekend was associated with a lower eGDR, a higher risk of type 2 diabetes.
The study authors wrote: “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.”
