Sleep Deprivation Affects More Than Your Mood—It's Linked to Chronic Disease Risk
Everyone knows a bad night's sleep can ruin your day. But routinely struggling to fall and stay asleep doesn't just affect your day-to-day life—it can have profound consequences on your overall health. A new study published in PLOS Medicine adds to a growing body of research suggesting that sleep—particularly REM sleep and deep sleep—plays a pivotal role in disease prevention.
Analyzing data from over 95,000 UK Biobank participants, researchers found that getting more REM sleep was associated with a lower risk of developing 83 diseases, including heart failure, atrial fibrillation, multiple sclerosis, and dementia. More deep sleep was linked to a lower risk of seven conditions, including type 2 diabetes, depression, osteoarthritis, and Parkinson's disease. Additionally, greater total sleep duration was associated with a lower risk of 50 conditions, many of which were endocrine diseases such as type 2 diabetes.
How Was the Study Conducted?
Participants' sleep patterns were tracked for seven days with wrist-worn accelerometers. The data were collected between 2013 and 2015, and participants were followed for about nine years. Researchers fed the accelerometer data into an algorithm to estimate how much time each participant spent in various sleep stages.
However, the study has notable limitations. "It is essentially a movement sensor. It does not measure brain waves, eye movements, or the other physiological signals used to determine sleep stages," says Michael A. Grandner, Ph.D., director of the Sleep and Health Research Program at the University of Arizona. "It may contain some information about what state someone is probably in, but there is so much uncertainty around the individual classifications that I would be very reluctant to interpret the resulting numbers as actual measurements of REM or deep sleep."
Grandner also points out that the algorithm used was shown to group non-REM stages of sleep together, so he'd be "especially cautious" when interpreting the study's deep sleep data. James Rowley, M.D., program director of the Sleep Medicine Fellowship at Rush University Medical Center and president of the American Academy of Sleep Medicine (AASM), notes that participants' sleep data was only collected during one seven-day period, although sleep patterns often change with age. "We do not know if changes in sleep patterns and stages would also contribute to health outcomes," he says.
What Does Sleep Have to Do with Disease Prevention?
While Grandner cautions that good sleep support is just one factor—and not "a medicine that prevents individual diseases"—he agrees it supports overall health. "Sleep and circadian rhythms interact with cardiovascular function, metabolism, immune function, hormonal regulation, brain function, and mental health," he says. "Chronically insufficient or disrupted sleep can place stress on many of these systems."
Dr. Rowley agrees. "Sleep directly supports the immune system to help fight disease, promote tissue repair, lower inflammation, and helps the mind and body feel restored," he says, pointing to a 2025 statement from AASM, which stresses that sleepiness "is associated with an increased risk for adverse health effects and diminished quality of life."
Why Might REM and Deep Sleep Be Particularly Important?
REM tends to occur later in the night and is thought to be important for supporting "aspects of learning, memory, and emotional processing," Grandner says. Deep sleep occurs earlier and has been linked to "processes involving memory and learning as well as cardiovascular, metabolic, and other aspects of physiological regulation," he adds.
Still, it's probably best not to stress too much about individual stages—and not only because estimates made by consumer wearables are often inaccurate. "I would resist the popular tendency to think that one is the 'good' or 'restorative' stage," Grandner adds. "Healthy sleep involves cycling through all of these states. They are different parts of a coordinated biological process."
What Can Individuals Do to Get Better Sleep?
Rather than focusing on boosting one particular stage or another, aim for solid sleep overall. Experts suggest the following strategies to support sleep hygiene:
- Allow adequate time for sleep
- Keep your bedroom cool, quiet, and dark
- Avoid excessive food and alcohol before bed
- Maintain a consistent sleep schedule
- Exercise during the day, but avoid vigorous workouts close to bedtime
- Limit caffeine and screen time, especially in the evening
If you want to track your sleep quality and related health metrics, the Xiaoshu Health App can sync with Apple Health to monitor relevant indicators, helping you better understand sleep trends, heart rate changes, and other data to support better sleep and chronic disease prevention.