DO WEIGHTED BLANKETS WORK? A weighted blanket used at bedtime is associated with the release of higher melatonin levels, as measured in the saliva. That is the finding of a new research study from Uppsala University (Sweden).
Sales of weighted blankets are on the rise. While research support for the health benefits of the blankets is not solid, many users offer that the extra weight is associated with less anxiety and can help with trouble sleeping.
Weighted blankets typically contain ball bearings, plastic pellets, or other objects to increase the weight beyond a standard cover or duvet.
Many of these heavier blankets weigh five to 30 pounds, with many sleepers most comfortable with a blanket that is approximately 10 percent of their body weight. Newer offerings include open-knit designs that many users find more breathable.
DO WEIGHTED BLANKETS WORK TO IMPROVE MENTAL HEALTH?
Weighted blankets purportedly provide health benefits. For example, Karolinska University (Stockholm, Sweden) evaluated the weighted chain blanket effects on insomnia and sleep-related daytime symptoms for patients with major depressive disorder, bipolar disorder, generalized anxiety disorder, and attention deficit hyperactivity disorder.
The Swedish investigators randomized 20 patients to a weighted metal chain blanket or a light plastic chain blanket for four weeks.
The researchers evaluated outcomes using the Insomnia Severity Index, day and night diaries, Fatigue Symptom Inventory, and Hospital Anxiety and Depression Scale. They evaluated the participants’ sleep and daytime activity levels with wrist devices (actigraphy).
This randomized controlled study showed this:
Weighted chain blankets significantly reduce insomnia severity and improve daytime symptoms in various psychiatric disorders (major depressive disorder, bipolar disorder, attention deficit hyperactivity disorder, or generalized anxiety disorder). An objective sleep assessment utilizing wrist actigraphy supported the observed clinical efficacy.
During a 12-month open follow-up phase of the study, those continuing to use weighted blankets maintained the sleep improvement, while individuals switching from a light to a weighted blanket affected Insomnia Severity Index ratings similar to that of participants using the weighted blanket from the beginning.
The researchers concluded that “weighted chain blankets are an effective and safe intervention for insomnia in patients with major depressive disorder, bipolar disorder, generalized anxiety disorder, or attention deficit hyperactivity disorder, improving daytime symptoms and levels of activity.”
Weighted blankets, sleep, and melatonin
Let’s turn to a small study published online in the Journal of Sleep Research. Twenty-six volunteers, including 15 men and 11 women, indicated that they had no sleep issues. One day before the first testing session, the participants visited the laboratory to be acclimated overnight.
Then, the subjects had two experimental test nights. For the first, they used weighted blankets, and for the second, a lighter blanket. The weighted blankets included honed glass pearls with polyester wadding, corresponding to 12.2 percent of each subject’s body weight. The blankets covered the arms, legs, abdomen, and chest.
After dimming the lights between 9 and 11 pm, the researchers collected saliva samples every 20 minutes between 10 and 11 pm. The subjects also completed the Karolinska Sleepiness Scale before the hour that researchers turned the lights off. They completed another survey the following morning.
Each subject recorded their experimental night sleep duration using the OURA ring. This multisensor wearable device tracked variables associated with sleep. The researchers also tracked overall sleep duration.
Here are the research findings:
- Melatonin concentrations rose by an average of 5.8 pg/mL between 10 and 11 pm. The average appeared greater with the weighted blanket (6.6 pg/mL), compared with five pg/mL during the lighter blanket session.
- Oxytocin rises did not appear different with the weighted versus unweighted blanket conditions.
- Cortisol levels did not appear different between the two types of blanket sessions.
- Sleepiness and total sleep levels did not change with the weighted blanket.
The researchers could not identify why the weighted blanket appeared linked with higher melatonin levels. They speculate that the pressure exerted by the weighted blanket activates skin sensory nerves that carry information to the brain. This activation stimulates oxytocin-related serve cells (in the brain) that promote calm and well-being while decreasing stress, fear, and pain. These neurons communicate with the brain’s pineal gland to influence melatonin release.
We often see melatonin in the wrong context
To senior author Dr. Christian Benedict, some people think of melatonin in the wrong context. Listen to him speaking to MDedge:
“Melatonin is not a sleep-promoting hormone. It prepares your body and brain for the biological night. Sleep coincides with the biological night, but it’s not like you take melatonin and have a very nice uninterrupted slumber.”
He adds that children with attention deficit hyperactivity disorder may benefit from melatonin supplements, as may the elderly who can no longer produce sufficient amounts of melatonin and for whom supplements may help promote sleep timing.
However, Dr. Benedict believes that — for even those who respond to melatonin supplements — the response is likely a powerful placebo effect for sleep promotion. Furthermore, he adds that just because the body makes melatonin does not mean that melatonin supplements are safe.
In children, melatonin may delay puberty onset. It may also impair blood glucose: If we are eating and have a lot of melatonin on board, the melatonin tells the pancreas to turn off insulin production, leading to higher blood levels of glucose (hyperglycemia).
Weighted blankets can be quite expensive. If you try one, let us know what you think. Thank you for joining me in this brief look at weighted blankets and health
However, Dr. Benedict cautioned that weighted blankets don’t come cheap. A quick Google search brings up examples that cost upwards of $350. “MDs can say try one if you can afford these blankets, but perhaps people can use several less costly blankets. But I think if there are cheap options, why not?
Dr. Benedict has reported no relevant financial relationships. Thank you for joining me today in this look at weighted blankets, sleep, and mental health. Have you ever tried one?
I hope you enjoyed “Do Weighted Blankets Work?” You might also want to read my previous piece on sleep:
The information I provided in this blog is for educational purposes only and does not substitute for professional medical advice. Please consult a medical professional or healthcare provider if you seek medical advice, diagnoses, or treatment. I am not liable for risks or issues associated with using or acting upon the information in this blog.
