Prader-willi syndrome

Prader-Willi syndrome (PWS) is a rare genetic condition. It causes a wide range of symptoms, such as:

  • a†constant desire to eat food, which seems to be driven by permanent hunger and can easily lead to dangerous weight gain
  • restricted growth
  • learning difficulties
  • behavioural problems, such as temper tantrums or stubbornness

See†Prader-Willi syndrome - symptoms for more information

Who is affected?

PWS is rare, affecting†no more than 1 in every 15,000 children born in England.†Boys and girls†of all ethnic backgrounds may be affected.

There are no known factors†that make†giving birth to a child with PWS more likely. It is caused by a fault in the child's chromosomes, which happens purely by chance. See Prader-Willi syndrome - causes†for more information.

Living with Prader-Willi syndrome

There is no cure for PWS, so treatment aims to manage the symptoms and associated problems. For parents, this†includes†dealing with†their child's behavioural problems and excessive eating.

See†Prader-Willi syndrome - management for more information.

Restricting your child's diet is a particularly important part of managing their condition. If children with PWS are allowed to eat as much as they want, they will quickly become dangerously overweight. They†will eat three to six times more than other children of the same age, and will probably still feel hungry.

However, restricting a childís diet is not easy. They can be highly obsessive and†sneaky when it comes to eating, and their hunger can cause them to hide or steal food.


While PWS itself is not life threatening, the compulsive eating and the resulting weight gain can be.

Younger adults with PWS often develop obesity-related conditions usually seen in older adults, such as†type 2 diabetes and†heart failure. If the†obesity is not treated, an adult with PWS will probably†die a lot younger than would normally be expected.

Compulsive eating can also cause health problems such as an abnormally expanded stomach and choking. Because of†the potential risk of choking, all parents of a child with PWS are advised to learn the Heimlich manoeuvre. See What should I do if someone is choking?

If a child with PWS manages to follow a restricted diet and control their weight, there is no reason why they cannot enjoy a good quality of life and take part in activities such as voluntary or part-time work. However, because of†their behavioural problems and learning difficulties, it is unlikely they will be able to live fully independent lives.

Information from NHS Choices

Mental Health Foundation
Mental Health Foundation
The Royal College Of Psychiatrists