Scientists named the exact sleep norm for protection against diabetes

The ideal sleep duration for protecting against insulin resistance is approximately seven hours and 18 minutes per day. This is the conclusion reached by scientists from the University of Hong Kong, who published the results of their work in the journal BMJ Open Diabetes Research & Care.

The researchers analyzed data from the large-scale U.S. National Health and Nutrition Examination Survey (NHANES), collected over the period from 2009 to 2023. The sample included 23,475 individuals aged 20 to 80 years. Each participant's sleep duration was compared with the eGDR indicator — an estimated measure of insulin sensitivity. The principle is simple: the lower this indicator, the higher the risk of developing insulin resistance.

Insulin resistance is considered one of the key precursors to type 2 diabetes, but this condition in itself does not mean the disease will inevitably develop. With timely lifestyle changes, it can remain stable for a long time without progressing.

The analysis results revealed a characteristic U-shaped relationship between sleep duration and metabolic health. The best eGDR values were recorded in those who slept an average of approximately 7 hours and 18 minutes. For people with sleep deficiency, increasing sleep duration was associated with improved glucose metabolism indicators. However, after passing the optimal mark, the picture reversed: additional sleep was associated with an increased risk of metabolic disorders — particularly in women and people aged 40 to 59.

The question of "catching up on sleep" on weekends deserves special attention. For those who are sleep-deprived during the workweek, one to two additional hours of sleep on weekends were associated with a more favorable metabolic profile. But if a person already sleeps enough or longer than the optimal time, more than two extra hours of sleep were, on the contrary, associated with worsening glucose metabolism indicators.

The study authors note that the results obtained are based on observational data and do not prove a direct cause-and-effect relationship. Nevertheless, they point to the importance of a balanced sleep schedule as a factor in preventing metabolic disorders.