More REM Sleep Linked to Lower Risk of 83 Diseases, New Study Finds

A new scientific study has found that people who spend more time in a particular stage of sleep associated with dreaming may have a lower risk of developing dozens of diseases, highlighting the importance of getting quality sleep.

The study, published in the journal PLOS Medicine on September 17, 2026, analysed sleep data from 95,559 participants in the UK Biobank research project. Researchers examined how different sleep stages, sleep duration and interruptions during the night were associated with the development of more than 1,000 health conditions.

The findings revealed that people who spent more time in rapid eye movement (REM) sleep had a lower risk of developing 83 diseases. These included heart failure, dementia, Parkinson’s disease, Alzheimer’s disease and multiple sclerosis.

However, researchers cautioned that the study identified associations rather than proving that more REM sleep directly prevents disease.

Why REM Sleep Matters

REM sleep is a stage of the sleep cycle characterised by rapid eye movements and increased brain activity. It is also the stage during which most vivid dreaming occurs.

During a typical night, people cycle through different stages of sleep, including light sleep, deep sleep and REM sleep. These stages perform different functions and contribute to the body’s overall recovery.

REM sleep is believed to play an important role in memory, learning and emotional processing. Because REM periods generally become longer during the second half of the night, waking up too early or regularly getting insufficient sleep may reduce the time available for this stage.

The new study adds to growing scientific interest in how the quality and structure of sleep may influence long-term health, beyond the total number of hours a person spends in bed.

Study Tracked Nearly 96,000 Adults

Researchers analysed data from 95,559 UK Biobank participants who wore wrist-mounted accelerometers for seven consecutive days and nights. These devices recorded movement patterns, allowing researchers to estimate sleep stages and other characteristics of sleep.

The participants were then followed for a median period of approximately 8.9 years. Their sleep measurements were compared with subsequent health records to investigate relationships between sleep patterns and the onset of different diseases.

The analysis found that greater amounts of REM sleep were associated with lower risks of 83 diseases across several health categories.

For example, approximately 48 additional minutes of REM sleep, when comparing participants with different levels of REM sleep, was associated with a 26 per cent lower risk of heart failure, a 46 per cent lower risk of dementia and an 80 per cent lower risk of parkinsonism.

These figures describe statistical associations observed in the study. They do not mean that deliberately adding 48 minutes of dreaming sleep would produce the same reductions in an individual’s disease risk.

The researchers also found that more deep sleep was associated with a lower risk of seven conditions, including type 2 diabetes and major depressive disorder.

Sleeping Too Little May Carry Risks

The study also highlighted the importance of total sleep duration.

Researchers found that people who regularly slept between six and eight hours had a more favourable risk profile for many of the health conditions examined. In contrast, those sleeping for less than five hours showed particularly widespread associations with increased disease risk.

Sleep irregularity and spending more time awake after initially falling asleep were also associated with higher risks of certain conditions, including anxiety disorders and major depressive disorder.

These findings suggest that maintaining a consistent sleep schedule and allowing sufficient time for uninterrupted rest may be important aspects of protecting long-term health.

Nevertheless, the appropriate amount of sleep can vary according to age, individual circumstances and health needs. The findings should not be interpreted as proof that everyone needs exactly the same number of hours.

Does Dreaming Regularly Mean You Are Healthier?

Although the headline finding focuses on dreaming, there is an important distinction between dreaming and REM sleep.

Most vivid dreams occur during REM sleep, but dreaming can also occur during other stages. Furthermore, remembering dreams depends partly on whether a person wakes up during or shortly after a dream.

Consequently, someone who frequently remembers dreams is not necessarily getting more REM sleep than someone who rarely recalls them.

The study measured sleep patterns using wrist-worn movement sensors and a computational algorithm. It did not establish that remembering dreams more frequently directly improves health.

Its observational design also means that other factors, including existing health conditions, lifestyle habits and environmental influences, may help explain some of the relationships.

Further research will be needed to determine whether changes in particular sleep stages can directly influence the development of specific diseases.

How to Support Better Sleep

Although people cannot reliably control how much REM sleep they experience on any given night, several practical habits can support healthier sleep patterns.

Maintaining a consistent bedtime and waking time can help regulate the body’s sleep-wake cycle. Creating a quiet, dark and comfortable sleeping environment may also make it easier to rest without unnecessary interruptions.

Avoiding excessive caffeine late in the day, limiting stimulating activities before bedtime and allowing enough time for sleep are other useful measures.

People who regularly experience severe daytime sleepiness, persistent insomnia, loud snoring or repeated episodes of interrupted breathing during sleep should consider seeking medical advice.

The main lesson from the research is that sleep health involves more than simply counting hours. The amount of time spent in different sleep stages, the regularity of sleep and the frequency of nighttime interruptions may all be relevant to long-term health.

However, the findings do not establish that dreaming itself prevents disease. For now, prioritising sufficient, regular and good-quality sleep remains a sensible step towards supporting overall wellbeing.

Source: Sun and colleagues, Accelerometer-derived real-world sleep stages and risk of incident diseases: A UK Biobank cohort study and phenome-wide association analysis, published in PLOS Medicine, September 17, 2026.

Research paper: https://doi.org/10.1371/journal.pmed.100521