According to a new study published September 17, greater amounts of REM and deep sleep were associated with lower risks of dozens of diseases, and less than five hours of total sleep were associated with high risks of diseases.th in the open access journal Additional medicine by Shengzhi Sun of Capital Medical University, China, and colleagues.
The quantity and quality of sleep is a priority of the National Health Commission of China and a focus of attention in China in general. The most recent China Sleep Health White Paper 2026 reveals that while the average Chinese surveyed sleeps 6.97 hours per night, 23 percent sleep less than 6 hours per night. The same report notes that only 26 percent of respondents reported a consistent sleep schedule and that sleep disturbances have increased over time. Therefore, understanding how sleep patterns are related to disease risk is of great relevance to Chinese citizens.
There remains limited understanding of how sleep stages and other real-world sleep patterns relate to health outcomes. In part, this is because self-reported sleep measures often show poor correlation with objective assessments, making it difficult to capture real-world sleep patterns.
In the new study, researchers analyzed data from 95,559 UK Biobank participants who wore wrist accelerometers for seven consecutive days and nights. The researchers used a deep learning algorithm to calculate sleep stages (REM, deep and light sleep), total sleep duration, wakefulness after sleep onset, and sleep irregularity from night to night. Participants were followed for an average of 8.9 years and medical records were available to evaluate associations with more than 1,000 disease outcomes.
Greater REM sleep (by interquartile range, 47.6 minutes) was associated with a lower risk of 83 diseases, including heart failure (hazard ratio 0.74), dementia (hazard ratio 0.54), and Parkinson’s disease (hazard ratio 0.20), while greater deep sleep was associated with a lower risk of 7 conditions, including type 2 diabetes and major depressive disorder. Greater sleep irregularity and greater wakefulness after sleep onset were associated with increased risk of several conditions, including anxiety and substance use disorders. Total sleep duration showed a nonlinear relationship with disease risk for many conditions, with the lowest risk concentrated in a 6- to 8-hour period; People who slept less than 5 hours faced the highest clinical vulnerability, with an increased risk of 37 conditions. However, as an observational study, this research cannot establish that sleep patterns directly cause disease risk.
“The findings provide additional evidence supporting the health-protective role of sleeping 6 to 8 hours for middle-aged and older adults, likely attributable to more favorable distributions of sleep stages,” the authors say. “Maintaining a sleep duration of 6 to 8 hours can effectively reduce the risk of multiple diseases, providing new insights for health promotion and preventive practice.”
The authors add: “The phenomenon-wide association analysis identified 156 significant associations between sleep patterns and incident illnesses after Bonferroni correction.”
“Sleep duration showed significant nonlinear associations with 86 disease phenotypes, and the duration of minimal risk for most of these conditions (69 phenotypes) was concentrated precisely in a period of 6 to 8 hours.”
This work was supported by the National Science Fund for Distinguished Young Scholars (82025031 to RC), the Key Program of the National Natural Science Foundation of China (82230109 to RC), the Beijing Outstanding Young Scientists Program (JWZQ20240101024 to RC), and the Beijing Young Scholars Project, the Chinese Institutes of Medical Research, Beijing (CX23YZ01 to RC). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.