The Gravity weighted blanket claims to reduce stress and anxiety and improve sleep. Its Kickstarter campaign aimed to raise $21,500. Remarkably, more than 23,000 backers pledged over $4.5 million dollars to bring the project to fruition. But can a weighted blanket really improve sleep, or is it all just marketing hype?
A 2015 study published in the Journal of Sleep Medicine & Disorders set out to determine whether the use of a weighted blanket had a positive impact on adults with chronic insomnia.
Can weighted blankets improve sleep in adults?
In the 2015 study, participants slept in their normal sleep environment (without a weighted blanket) for one week so researchers could gather baseline data. Participants then slept with a weighted blanket every night for two consecutive weeks. Sleep quality was measured through an actigraphy watch, polysomnography, and sleep diaries.
Actigraphy data found that when using a weighted blanket, participants were less active during the night. Those who were taking sleeping pills also fell asleep faster and spent less time in bed when using a weighted blanket.
Polysomnography (PSG) data collected during a sleep study found no significant differences in sleep architecture during weighted blanket use other than a decrease in the spindles index (sleep spindles are bursts of brain activity that occur during sleep). However, when researchers isolated data from participants who said they liked using the blanket, PSG data found a significant decrease in time spent awake during the night and a significant increase in total sleep duration.
Participants reported some subjective improvements in sleep when using the weighted blankets. Specifically, participants reported that they found it easier to settle down to sleep; enjoyed a much better quality of sleep; and felt more refreshed in the morning.
How do weighted blanked improve sleep?
As pointed out by the authors of this study, previous research has suggested that the pressure and constant sensation provided by a weighted blanket can help reduce arousal.
Past studies have also suggested that pressure exerted on the body through weighted vests and blankets may promote calm and encourage relaxation among those with autism spectrum disorders, attention-deficit hyperactivity disorder, and other developmental disorders.
The application of deep pressure has also been found to offer some benefit to children with high levels of anxiety or arousal, and some nursing homes are experimenting with weighted blankets to offer relief to elderly individuals suffering from anxiety and dementia.
How to choose a weighted blanked to improve sleep
The authors of the study suggested that for a weighted blanket to be effective:
- It should not be too light or heavy.
- Its weight must be evenly distributed.
- It should weight more than 10 percent of your body weight. (In the study, all participants used a blanket that was more than 12 percent of their body weight.)
Although this study found weighted blankets had a positive impact on sleep, the number of participants was small and (an important point) it was supported by a grant from a weighted blanket manufacturer. That being said, it makes sense that a product that could help reduce arousal and anxiety can improve sleep, as these two factors do contribute to insomnia.