Most people associate dreams with REM sleep, but this stage of sleep is also where much of the brain’s emotional and cognitive recovery takes place.
When REM sleep is consistently short or fragmented, mood swings, irritability, emotional sensitivity, brain fog, or a sense of mental exhaustion that does not improve with rest are common.
What is REM sleep?
REM stands for rapid eye movement, a phase of sleep where brain activity increases while the body remains largely immobile (the name comes from the quick, involuntary eye movements that occur beneath closed eyelids).
During this stage, the brain actively works through information, emotions, and internal signals that were not fully processed during the day.
REM sleep helps:
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process emotional experiences and reduce emotional reactivity
- consolidate learning and memory
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regulate the nervous system
- support creativity and cognitive flexibility
Most adults spend about 20 to 25 percent of their total sleep time in REM. Children spend a larger proportion, closer to 30 percent, with REM decreasing through adolescence and reaching adult levels by the late teenage years.
Why REM Sleep Can Be Low Even When You Get 8 Hours of Sleep
Low REM sleep is often interpreted as a problem of insufficient sleep time, but REM depends less on duration and more on whether sleep remains continuous.
For REM to occur in longer periods, the body has to move through complete sleep cycles without being repeatedly pulled back into lighter stages. Because REM appears later in the night and builds across successive cycles, even subtle instability can interrupt that progression.
Fragmented sleep causes the brain to restart cycles instead of completing them, which shortens or eliminates REM despite an apparently adequate amount of time spent asleep.
The Nervous System’s Role in REM Sleep
REM sleep requires a certain level of safety. From a physiological perspective, the brain does not allow REM when the nervous system perceives threat, tension, or instability.
When stress levels are high, the body remains closer to a fight-or-flight state. Because of this, the heart rate stays elevated, breathing patterns become less regular, and the brain prioritizes vigilance over recovery. In that state, deep sleep and REM both become harder to sustain.
This is why people under chronic stress often report vivid dreams during short windows of REM, followed by abrupt awakenings, or long nights with very little dreaming at all.
If you are trying to understand how to increase REM sleep, the focus should be on keeping the nervous system calm and stable once sleep begins.
Habits That Affect REM Sleep
Inconsistent sleep timing
REM sleep is tied closely to circadian rhythm timing and tends to occur in longer stretches later in the night, so when bedtime and wake time shift from day to day, the internal clock becomes misaligned and the later REM-heavy cycles are the first to be compressed or skipped.
Keeping a consistent wake time anchors the circadian rhythm and allows sleep cycles to progress predictably, which supports longer REM periods across the night.
Drinking alcohol close to bedtime
Research has shown that drinking alcohol before sleep changes normal sleep architecture and reduces REM sleep. Alcohol has been observed to delay the onset of the first REM period and decrease the total amount of REM sleep across the night, even at low to moderate doses.
Higher doses tend to suppress REM more strongly, and the first REM period can be pushed later or shortened as the body metabolizes the alcohol, contributing to fragmented sleep and increased wakefulness later in the night.
Late-night stimulation
As we’ve already mentioned, for REM sleep to occur in longer periods, the nervous system has to downshift into a calmer state, and late-night activity keeps that from happening.
It can be anything that keeps the nervous system active close to bedtime, like working out late, eating late, or scrolling in your bed. These inputs do not stop you from falling asleep, but they can keep sleep shallower and less stable.
A disruptive sleep environment
If you are having trouble getting enough REM sleep, the easiest place to start is your sleep environment. Unlike habits that take weeks to change, the environment around you can usually be adjusted immediately, and it has a direct effect on how stable your sleep is once you fall asleep.
Both light and sound can make sleep either more stable or easier to disrupt, depending on how much of each is present, so an eye mask, earplugs, or a fully darkened room can help.
How To Increase Rem Sleep Naturally
REM sleep depends on sleep remaining stable long enough for full sleep cycles to complete, especially in the second half of the night. When the nervous system stays activated, sleep becomes lighter and more fragmented, and REM periods are shortened or skipped.
Kimba works at the level where REM sleep is most vulnerable: sleep stability and nervous system regulation.
When it senses signs that sleep is destabilizing, whether that's rising restlessness, movement, or a shift toward lighter sleep, it responds with short, precisely timed pulses of scent through the olfactory system, which has a direct connection to brain regions involved in emotional regulation and autonomic balance.
Unlike a diffuser that fills the room continuously, these pulses are brief and targeted, designed to support nervous system settling during the exact moments when sleep begins to destabilize, rather than running on a fixed schedule regardless of what your body needs.
Over time, Kimba's AI learns your patterns, refining when and how it responds so that support becomes more precise the more you use it. In clinical testing, this approach has been associated with up to 32% more REM sleep, alongside fewer nighttime disruptions overall.
Frequently Asked Questions
Can you increase REM sleep on purpose?
Not directly, but you can create the conditions REM depends on. Since REM builds later in the night and needs the nervous system to stay calm and undisturbed, protecting sleep stability through consistent timing, a calm environment, and avoiding late-night stimulation gives REM more room to occur.
Does getting more sleep guarantee more REM sleep?
Not necessarily. REM depends more on how stable and uninterrupted your sleep is than on total hours. It's possible to spend eight hours in bed and still get very little REM if sleep is fragmented or the nervous system stays activated throughout the night.
Can stress reduce REM sleep even if I fall asleep easily?
Falling asleep and sustaining REM are regulated differently. A stressed nervous system can make it easy to drift off but harder to stay in the calmer state REM requires later in the night, which is why REM can be short even after a normal bedtime.
Does alcohol before bed affect REM sleep?
Alcohol has been shown to delay and reduce REM sleep, even at low to moderate doses, and higher doses suppress REM more strongly while also increasing wakefulness later in the night as the body metabolizes it.
How does Kimba support REM sleep?
Kimba works using its own built-in sensors, and can also connect to a wearable for even more precision, monitoring your body throughout the night.
When it senses signs that sleep is destabilizing, it responds with short, timed pulses of scent designed to support nervous system settling, helping create the stability REM sleep depends on.
