Curling up under a weighted blanket is promoted as a way to reduce insomnia and improve sleep quality. A new review now adds some scientific credibility to the use of heavy comforters and quilts as sleep aids.

Blankets made with extra mass give the body the feeling of a warm hug while sleeping. According to research by led by researchers from Flinders University and the University of Adelaide in Australia, this added snug factor has three key benefits: they boost mood, they reduce reliance on sleep medication, and they improve sleep.

The team behind the review says the evidence is strong enough for weighted blankets to be officially recommended by health professionals.

"In occupational therapy, weighted blankets are becoming more common amongst many ages as an assistive technology, but no current clinical guidelines exist for their use," says Flinders University occupational therapist Suzanne Dawson.

The team looked at 18 previous studies analyzing the effects of using weighted blankets overnight. While the studies differed in detail, involving anywhere from a single participant to 4,092 volunteers, the researchers matched data to conclude that weighted blankets did have a positive effect, in the quality of sleep, for example, and how quickly people slipped into slumber.

Curiously, those findings only apply to adults. Results were more mixed for children with ADHD (attention deficit hyperactivity disorder) or ASD (autism spectrum disorder) – though many individual kids stated they personally found weighted blankets helpful.

"Parents often reported that their children appeared more relaxed, less anxious, and more focused during daily activities when using the blankets, which could have a long-term impact on their overall well-being," says Dawson.

Previous studies have looked at the benefits of hugs and other forms of human touch, and it seems as though the way that weighted blankets replicate those physical feelings bring benefits for our bodies.

Further investigation is needed to confirm the pros and cons of weighted blankets for children, say the researchers. In addition, whenever a weighted blanket is used with a kid with cognitive difficulties, it ought to be one that's easy for the young person to remove themselves.

The review was carried out with the intention of developing clinical guidelines for the use of weighted blankets, and in starting to formalize some standards for the design of these blankets (in terms of weight and materials, for example).

Though there are some limitations to consider, including the low number of participants in some of the reviewed studies, the use of heavy blankets is a relatively straightforward way of improving sleep that most people can try.

"Sleep is a basic human need," says Dawson.

"When someone isn't getting enough, it can lead to numerous health issues as well as increase the risk of, or exacerbate, chronic conditions, including heart disease, stroke, and mental health issues."

The research has been published in the American Journal of Occupational Therapy.