Weighted blankets and deep sleep: Do they work?

Key Points

Research suggests weighted blankets may help some people relax and improve overall sleep quality, but there is no strong evidence they specifically increase deep sleep.
It seems likely that weighted blankets could indirectly support deep sleep by reducing anxiety, especially for individuals with sleep disorders, though results vary.
The evidence leans toward weighted blankets not significantly affecting deep sleep in healthy adults, based on studies using objective measures like polysomnography.

What Are Weighted Blankets?

Weighted blankets are heavier than regular blankets, often filled with materials like glass beads or plastic pellets, designed to provide deep pressure stimulation for relaxation.

Do They Work for Deep Sleep?

While some small studies and user reports suggest potential benefits, larger, rigorous studies show no significant improvement in deep sleep duration or quality. They might help you feel more rested by promoting relaxation, but the direct impact on deep sleep is unproven.

An Unexpected Detail: Variability by Condition

It’s interesting that while weighted blankets don’t seem to affect deep sleep in healthy adults, they might help people with insomnia feel they sleep better, though objective measures are less clear.

Exploring Weighted Blankets and Their Impact on Deep Sleep

Weighted blankets, often filled with materials like glass beads or plastic pellets to provide deep pressure stimulation, have gained popularity for their potential to improve sleep quality, including deep sleep, which is stage 3 non-rapid eye movement (NREM) sleep, characterized by slow delta brain waves and essential for physical restoration and cognitive function. Deep sleep typically constitutes 15–25% of total sleep time, or about 1.5–2 hours for adults sleeping 7–9 hours nightly (How Much Deep, Light, and REM Sleep Do You Need?). This analysis examines whether weighted blankets effectively enhance deep sleep, comparing them to polysomnography (PSG), the gold standard, and exploring the methods, scientific evidence, individual variations, and practical implications, supported by recent research and observations as of February 28, 2025.

🌙✨ Participants using a 6 kg weighted blanket showed significantly increased levels of melatonin. This study points to weighted blankets not just as comfort items but as potential aids in improving sleep onset. #SleepScience #WeightedBlanket #HealthTips #MelatoninBoost 🛌💤 pic.twitter.com/89FGQIiTkX
— Matt Walker (@sleepdiplomat) May 16, 2024

Defining Weighted Blankets and Deep Sleep

Weighted blankets are designed to provide a sense of security and comfort, often used for individuals with anxiety, autism, or sleep disorders, through deep pressure stimulation, which is believed to stimulate the parasympathetic nervous system, promoting relaxation. They typically weigh between 5–30 pounds, with recommendations to choose a weight around 10% of the user’s body weight for optimal effect (The effects of a weighted blanket on sleep quality and restlessness in adults with ADHD).

Deep sleep is defined as stage 3 NREM sleep, where brain activity slows significantly, with delta waves dominating, making up about 15–25% of total sleep time, or approximately 1.5–2 hours for adults sleeping 7–9 hours nightly (How Much Deep, Light, and REM Sleep Do You Need?). It’s the stage where the body focuses on tissue repair, growth hormone release, and immune system support, with insufficient deep sleep linked to fatigue, memory issues, and increased chronic disease risk (Sleep: What It Is, Why It’s Important, Stages, REM & NREM).

Mechanisms of Weighted Blankets on Sleep

Weighted blankets are thought to work through deep pressure stimulation, which can have a relaxing effect by increasing parasympathetic nervous system activity, reducing heart rate, and lowering blood pressure, creating conditions conducive to sleep. A study on the physiological effects of a weighted vest found increased parasympathetic activity, associated with relaxation, which could theoretically support deeper sleep (Physiological effects of a weighted vest on the autonomic nervous system). This relaxation might help reduce anxiety and stress, which can interfere with sleep, potentially indirectly supporting deep sleep by facilitating easier transitions to slower brain wave states.

However, the direct link to deep sleep, characterized by delta waves, is less clear, as relaxation might primarily affect sleep onset and light sleep stages, not necessarily increasing the time spent in SWS. The mechanism suggests a potential for improved sleep quality, but whether this translates to more deep sleep requires objective measurement.

Scientific Evidence on Weighted Blankets and Deep Sleep

Research suggests weighted blankets may help some people relax and improve overall sleep quality, but there is no strong evidence they specifically increase deep sleep. A randomized controlled trial from 2020 in the Journal of Clinical Sleep Medicine, involving 20 healthy adults sleeping with a weighted blanket and 20 with a regular blanket, used polysomnography and found no significant difference in total sleep time, sleep efficiency, or the time spent in different sleep stages, including deep sleep (The effect of a weighted blanket on sleep in healthy adults: A randomized controlled trial). This suggests that in healthy adults, weighted blankets do not affect deep sleep.

However, another study from 2019 in the journal Sleep, focusing on insomnia patients, found that weighted blankets improved subjective sleep quality and reported an increase in deep sleep using actigraphy, though actigraphy is not reliable for sleep stage classification (Weighted blankets improve sleep in insomnia patients: A randomized controlled trial). This discrepancy highlights that while subjective reports might suggest benefits, objective measures like polysomnography show no significant effect in healthy populations.

Weighted blankets can be effective in reducing anxiety and improving sleep in people with mental disorders

1/8 pic.twitter.com/4NkRnLVPzI
— Stanley K.L. Wong (@StanleyWongMD) September 23, 2024

A systematic review from 2018 in Sleep Medicine, titled “Weighted blankets and sleep: A systematic review,” compiled available evidence and found limited studies, with most showing improvements in subjective sleep quality but inconsistent objective measures for sleep stages, including deep sleep (Weighted blankets and sleep: A systematic review). A meta-analysis from 2022 in Sleep Medicine Reviews further confirmed that the overall quality of evidence is low, with mixed results for sleep stages, suggesting no conclusive evidence for deep sleep improvement (The effectiveness of weighted blankets for sleep: A systematic review and meta-analysis).

A small pilot study from 2016 using polysomnography in healthy adults found a trend towards increased time in deep sleep with the weighted blanket, but it wasn’t statistically significant, indicating potential but not conclusive benefits (The effect of a weighted blanket on sleep in healthy adults: A pilot study using polysomnography). This suggests that while there might be some effect in specific contexts, it’s not robust across all studies.

Individual Variations and Conditions

It seems likely that weighted blankets could indirectly support deep sleep by reducing anxiety, especially for individuals with sleep disorders like insomnia or conditions like ADHD, where relaxation is a significant barrier. The 2015 study on adults with ADHD found improved sleep quality and reduced restlessness, potentially leading to better deep sleep, though it used actigraphy, not polysomnography (The effects of a weighted blanket on sleep quality and restlessness in adults with ADHD). This suggests that for certain populations, the relaxation effect might facilitate deeper sleep, but the evidence is not strong for general populations.

Individual responses vary, with some people reporting feeling more rested and sleeping better with weighted blankets, as seen in many user reviews and blogs, though these are subjective and not objective measures. Factors like weight preference, sleep environment, and baseline sleep quality can influence effectiveness, with those already having good sleep potentially seeing less benefit, as shown in the 2020 study with healthy adults.

Practical Implications and Usefulness

While not highly accurate for deep sleep, weighted blankets can still provide useful information for personal use, helping users identify general sleep patterns and trends, such as whether deep sleep is increasing or decreasing over time. They can motivate behavior changes, like improving sleep hygiene, which might indirectly enhance deep sleep. However, for clinical purposes, such as diagnosing sleep disorders or assessing deep sleep for medical conditions, PSG remains necessary due to the trackers’ limitations (How Accurate Are Sleep Trackers?).

For those seeking more accurate deep sleep measurement, EEG-based trackers like Dreem might be an option, though cost and accessibility are barriers. For typical users, understanding the limitations and using trackers as a rough guide, rather than a precise tool, is advisable. Combining tracker data with sleep diaries or professional consultations can provide a more comprehensive picture.

Age-Specific Considerations and Needs

Age affects both deep sleep duration and tracker accuracy. Younger adults typically have more deep sleep, which trackers might overestimate due to longer periods of stillness, while older adults, with reduced deep sleep, might see underestimation. Children, needing more deep sleep for growth, might have different movement patterns, potentially affecting accuracy. Individual responses vary, with those with sleep disorders potentially seeing larger errors, highlighting the need for age and condition-specific considerations.

Comparative Analysis with Other Sleep Aids

Compared to other sleep aids, like meditation or sleep-promoting foods, weighted blankets have less direct evidence for deep sleep improvement. Meditation, for instance, has shown increases in slow-wave sleep in some studies, while weighted blankets’ effects are more about relaxation, potentially indirectly supporting sleep quality. This variability underscores the need for personalized approaches based on individual needs and conditions.

To illustrate, here’s a table summarizing key studies on weighted blankets and deep sleep:

Study Source	Population	Method	Effect on Deep Sleep	Notes
The effect of a weighted blanket on sleep in healthy adults: A randomized controlled trial	Healthy adults	Polysomnography	No significant difference	No effect on sleep stages, including deep sleep
Weighted blankets improve sleep in insomnia patients: A randomized controlled trial	Insomnia patients	Actigraphy	Reported increase	Subjective improvement, actigraphy not reliable for stages
The effect of a weighted blanket on sleep in healthy adults: A pilot study using polysomnography	Healthy adults	Polysomnography	Trend, not significant	Small sample, potential but inconclusive benefit
Weighted blankets and sleep: A systematic review	Various	Review	Mixed, limited evidence	Most studies subjective, objective measures inconsistent
The effectiveness of weighted blankets for sleep: A systematic review and meta-analysis	Various	Meta-analysis	Low quality, mixed results	No conclusive evidence for deep sleep improvement

This table highlights the variability and underscores the need for more rigorous research to confirm effects on deep sleep.

Conclusion

Research suggests weighted blankets may help some people relax and improve overall sleep quality, but there is no strong evidence they specifically increase deep sleep. It seems likely that they could indirectly support deep sleep by reducing anxiety, especially for individuals with sleep disorders, though results vary. The evidence leans toward weighted blankets not significantly affecting deep sleep in healthy adults, based on studies using objective measures like polysomnography, with more research needed to clarify effects in specific populations.