One Type of Sleep Linked to Lower Risk of 83 Diseases, Study Finds - Newsweek

The type of sleep you're getting each night could be influencing your risk of more than 80 diseases, a new study has found.

Researchers from Peking University and Capital Medical University in Beijing found that getting more REM sleep—the stage of sleep where most dreaming occurs—at night was associated with a lower risk of 83 diseases. Meanwhile, greater deep sleep—the most physically restorative stage of sleep—was associated with a lower risk of seven diseases.

The findings were published in the journal PLoS Medicine on September 17. Newsweek has contacted the study leads via email for comment and is awaiting responses.

"Sleep is crucial for physical and mental health and for regulating physiological and behavioral processes, so it is not surprising that poor sleep is associated with the development of so many diseases," Nour Makarem, co-director of the Chronic Disease Unit at Columbia University, told Newsweek.

"This study adds to the evidence showing that not getting enough deep and REM sleep and having insufficient, irregular, and fragmented sleep increase risk of disease, including cardiometabolic, neurodegenerative, and mental health conditions among others."

During REM sleep, our eyes move rapidly in various directions even though they are closed, and this stage is strongly linked with vivid dreaming.

It is considered a particularly important stage of sleep as it is thought to benefit our cognitive functions, by supporting emotional regulation, contributing to brain development, improving mental health and enhancing learning and memory.

Meanwhile, deep sleep is when brain activity slows down significantly. This is when tissue repair takes place and the glymphatic system removes metabolic waste as well as many other functions.

The researchers analyzed data from wrist accelerometers worn by more than 95,000 U.K. Biobank participants. After wearing the wrist accelerometers for a week, the participants were then followed for a median period of 8.9 years until the onset of a health condition or death.

The experts found that increased REM sleep duration was associated with a lower risk of dozens of diseases including: heart failure, hypotension, parkinsonism (the umbrella term for brain conditions that cause slowed movements and tremors), multiple sclerosis, as well as dementia and Alzheimer's disease.

The findings also indicated that increased deep sleep duration was associated with a lower risk of diseases including type 2 diabetes, major depressive disorder, sleep apnea, and Parkinson's disease.

Although, the researchers note that the links to some of these health conditions could be down to "reverse causation," meaning the symptoms of the condition result in changes to sleep patterns, rather than the other way round. For example, this could be behind the association with depression, as a symptom of depression is disrupted sleep.

The experts also found that greater light sleep duration was associated with higher risks of conditions like depression, but lower risks of heart failure and cellulitis, while being awake for longer throughout the night was associated with an increased risk of abdominal pain, anxiety and depression. Sleeping for longer overall was also associated with a lower risk of around 50 conditions, including type 2 diabetes.

The researchers concluded that those who slept between six to eight hours a night seemed to have the best sleep patterns, as well as the lowest risks for various diseases.

"My reaction is that the findings confirm the well-accepted concept that sleep is a pillar of health and well-being and that sleep deficiency increases the risk of poor health and illness," Eve Van Cauter, a professor of medicine at the University of Chicago, told Newsweek.

Girardin Jean-Louis, director of the Center on Translational Sleep and Circadian Sciences at the University of Miami, told Newsweek that the findings also "reinforce the notion that sleep duration should not be the sole factor to consider in understanding sleep health," as "sleep architecture, regularity, and fragmentation may each carry important information about future disease risk."

However, he added that one important limitation of the study was that sleep stages were estimated from wrist accelerometry rather than measured directly with polysomnography, which he said was "the gold standard in sleep medicine."

"These tools are quite useful for estimating sleep in large populations, however they do not yet provide the same physiological precision as do polysomnographic sleep studies," he said. "Caution should be exercised when inferring sleep stages from wearable devices."

He said that while the study has "identified important associations," it does not "incontrovertibly show that changing a specific sleep stage will prevent disease."

"The next step may be to replicate these findings in more diverse populations and determine which sleep features are indeed causal pathways versus early markers of disease development," he added.

Van Cauter said that all life on Earth has adapted to the "24-hour rotation of our planet on its axis and circadian sleep/rest behavior is part of this adaptation," meaning that sleep "affects each and every aspect of physiology."

For example, "in the brain, sleep facilitates the recovery of neuronal transmission from daytime stimulation and helps to clear waste products accumulated in the interstitial space," she said.

Makarem also said that "poor sleep is linked to hormonal imbalances, positive energy balance, and craving unhealthy foods predisposing to weight gain and its cardiometabolic consequences such as diabetes, hypertension, and heart disease."

She added that poor sleep can also "increase stress, inflammation, and oxidative stress and disrupt the body's circadian rhythms," and collectively, "these mechanisms among others can predispose to disease.

In light of the findings, Makarem said "we need pragmatic interventions that promote sleep health in real-world settings and sleep needs to be addressed, alongside diet and physical activity, in lifestyle interventions for supporting healthy longevity and reducing the chronic disease burden in the population."

Van Cauter also said that "education about the importance of sleep for health and well-being needs to start in kindergarten and continue through high school with increasing depth and complexity as the child matures."

Luo J, Liu R, Yin J, Cao W, Sun S, Chen R (2026) Accelerometer-derived real-world sleep stages and risk of incident diseases: A UK Biobank cohort study and phenome-wide association analysis. PLoS Medicine. https://doi.org/10.1371/journal.pmed.1005213