REM Sleep Linked to Lower Risk of 83 Diseases Including Dementia and Heart Failure
A study of more than 95,000 people found that more time in REM sleep is associated with a lower risk of 83 different diseases, including dementia and heart failure. Sleeping fewer than five hours per night was linked to increased risk for 37 conditions.
A large study of more than 95,000 individuals found that spending more time in REM sleep is associated with a lower risk of 83 different diseases, including dementia and heart failure, according to research published in September 2026.
The study also found that sleeping fewer than five hours per night was linked to increased risk for 37 conditions.
REM sleep, or rapid eye movement sleep, is the stage of sleep associated with dreaming and memory consolidation. It typically makes up about 20 to 25 percent of total sleep time in healthy adults.
Researchers tracked participants over time and analyzed their sleep patterns alongside health outcomes. The findings add to a growing body of evidence connecting sleep quality and duration to long-term health.
Dementia and heart failure were among the most notable conditions associated with reduced REM sleep. Both are leading causes of disability and death in the United States and globally.
Sleep experts have long recommended that adults aim for seven to nine hours of sleep per night. This study suggests that the composition of that sleep, not just the total duration, matters for health outcomes.
Practical steps to improve REM sleep include maintaining a consistent sleep schedule, limiting alcohol consumption, reducing screen time before bed, and managing stress. People with sleep disorders such as sleep apnea, which disrupts sleep architecture, are encouraged to seek treatment.
