More REM and Deep Sleep Linked to Lower Risk of Numerous Diseases, Study Finds

Consistently poor sleep increases the risk of developing numerous diseases, according to a recent study from Capital Medical University in China. The research, published in the journal PLOS Medicine, found that individuals who experienced more REM (rapid eye movement) sleep had a lower likelihood of 83 diseases. These included Parkinson's disease, dementia, heart disease, high blood pressure, and heart failure. Additionally, greater amounts of deep sleep were associated with a reduced risk of seven diseases, such as sleep apnea, depression, Parkinson's disease, and type 2 diabetes.

The study tracked the sleep patterns of 95,559 participants using wrist accelerometers for one week. Researchers monitored sleep duration and time spent in each sleep stage, correlating this data with participants' health records until their passing, disease onset, or April 1, 2024. The participants, with a median age of 56 and 43.7% male, were followed for a median of 8.9 years.

Researchers determined that individuals sleeping six to eight hours per night experienced the most significant health benefits. The study authors noted in a press release that these findings "provide additional evidence supporting the role of a 6-8 hours’ sleep duration as a health safeguard for middle-aged and older adults, likely attributable to more favorable distributions of sleep stages." They further stated, "Maintaining a sleep duration of six to eight hours can effectively reduce the risk of multiple diseases, providing new insights for health promotion and preventive practice."

Conversely, those sleeping less than five hours nightly showed worse health outcomes and a higher disease risk. Sleep irregularity, defined as inconsistent sleep durations or frequent awakenings during the night, was linked to an increased likelihood of conditions such as osteoarthritis, alcohol abuse, anxiety, and stomach pain.

The study acknowledges limitations, including tracking sleep for only one week, which may not account for long-term changes. The participant pool was also not diverse, with 96.9% being white, and all participants were healthy at the study's outset, potentially limiting the applicability of the findings to other demographics. The possibility of "reverse causation" was also noted, where conditions like depression or anxiety might influence sleep patterns rather than the other way around.

To improve sleep quality and increase REM and deep sleep, experts recommend prioritizing sufficient, uninterrupted sleep. The Centers for Disease Control and Prevention recommends at least seven hours of sleep per night for adults. Establishing a consistent sleep schedule, going to bed and waking up around the same time daily, can enhance sleep quality.

Avoiding stimulants like caffeine in the afternoon, ideally at least six hours before bed, and refraining from alcohol consumption, which can disrupt REM sleep, are also advised. Creating a relaxing bedtime routine—such as reading, taking a warm shower, or gentle stretching—can promote better sleep. Regular exercise also benefits sleep, as does minimizing exposure to light-emitting devices like phones and televisions before bed. Addressing underlying sleep disorders, such as obstructive sleep apnea, is crucial for achieving restful sleep. While increased sleep may not eliminate all disease risks, it contributes significantly to overall health, energy levels, and mood.