DEAR DOCTORS: My niece got me a weighted blanket for my birthday, which she says helps you sleep. I admit I was sceptical, but I used it for a month, and she may be right. Instead of waking up a few times at night, I sleep right through. Is it the power of suggestion, or is there a reason this is working?
DEAR READER: Weighted blankets have become increasingly popular in recent years. They were originally developed as a therapeutic tool to help people with conditions such as autism, in which anxiety can be a persistent symptom.
Unlike an ordinary comforter, which is made entirely of fabric, the interior of a weighted blanket is lined with a heavy material of some kind. Depending on the manufacturer, this may be tiny spheres made of glass, plastic or metal, or natural fillers such as rice, grain, beans or sand. These fillers are sewn into pockets or channels and arranged so that their weight is distributed evenly throughout the blanket.
Someone lying under a weighted blanket feels a sensation of gentle pressure evenly distributed across their entire body. Occupational therapists refer to this as deep touch pressure. Research has found that this type of compression activates the centres of the brain that oversee involuntary processes such as heart rate, blood pressure, respiration and digestion. It has long been used, often to beneficial effect, on individuals with a wide range of sensory disorders.
Studies looking into weighted blankets over the years have observed a range of potential benefits. These include easing insomnia in adults living with depression, anxiety and attention deficit disorders; lowering anxiety in some children with mental health disorders; and improving sleep in older adults living in a nursing home. The researchers noted that while using a weighted blanket, the participants in their studies were able to fall asleep more easily, woke less frequently during the night and felt an increased sense of calm during the day.
A new study in Sweden has potentially linked the use of weighted blankets to increased melatonin production. Melatonin is a hormone that plays an important role in the sleep-wake cycle. Researchers found that when a group of 26 young adults with no previous sleep problems used a weighted blanket at night, their bodies produced more melatonin than when sleeping with a conventional blanket. It's a small and short study -- just two days -- but the results take the weighted blanket conversation in an intriguing direction.
The accepted guidance regarding weighted blankets is to select a product that is 10% or less of the person's total body weight. The specific material used in the filling is a matter of personal preference. However, weighted blankets are not for everyone. They should never be used by or on someone who would not be able to remove the covering themselves. This includes infants, young children and older or frail adults. They also may be unsuitable for people living with certain medical conditions, such as Type 2 diabetes, asthma, sleep apnea, low blood pressure and circulatory problems. Universal Features Syndicate
Dr Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health.