People with anorexia do not wish to starve themselves to death, but they may deny the seriousness of a very low body weight.
If you have anorexia you may have an intense fear of gaining weight and losing control of your body shape. Your focus on food may become a means of controlling your life. You may feel life is just happening to you and that what you eat is the one part of your life you are able to control. To exercise control over your body shape, you may use restrictive dieting and/or intense exercise programmes. You may also use laxatives and diuretics.
Although it is likely that there is some link to the importance modern society places on being thin, the causes of anorexia nervosa are complex and are also linked to feelings of control and self-worth.
Anorexia nervosa often starts between the ages of 15 and 25, but it can develop in children as young as 10 and in older people. Although 90% of those who develop anorexia are women, the condition also affects men. Anorexia nervosa is found in all social groups and almost all cultural groups.
It is difficult to estimate how widespread anorexia nervosa is, but surveys suggest that 1% of young girls (age 15-25) have the condition.
The symptoms of anorexia nervosa include loss of weight and changes in other physical features, together with changes in personality and behaviour.
The physical changes that anorexia nervosa can cause include:
Women with anorexia often find that their periods stop. Anorexia can cause a loss of libido (sex-drive) in both men and women. In children and teenagers it can delay puberty and cause problems with physical development.
Anorexia nervosa can also cause personality and behavioural changes. A person with anorexia may:
There is no single cause of anorexia nervosa. It is a complex condition probably caused by a variety of factors.
These factors may include:
Diagnosis of anorexia nervosa can be difficult as most people with the condition deny that they are ill and are usually brought to treatment by a family member. Also, anorexia varies in severity between individuals. A person with anorexia may visit their GP because of symptoms such as their periods stopping, abdominal pain, bloating or constipation.
Diagnosis involves an assessment of both psychological and physical factors. It may involve an evaluation of the persons attitude to weight, food, dieting and body image.
A person with anorexia typically weighs at least 15% less than the expected weight for their height and age. Another way of defining anorexia is using Body Mass Index (BMI). A normal BMI for an adult is between 20 and 25. Adults with anorexia have a BMI of less than 17.5.
A doctor will need to rule out other physical conditions such as diabetes and an overactive thyroid gland, which can cause weight loss and other symptoms associated with anorexia.
Anorexia is a serious and complex illness and usually requires specialist medical care.
Guidelines published by the National Institute for Clinical Excellence (NICE) in January 2004 set the standard for NHS treatment of eating disorders in England and Wales.
The main guidelines for the treatment of anorexia nervosa are:
Treatment for anorexia aims to encourage weight gain and healthy eating habits so that the person achieves a normal weight for their age and height. Treatment is usually most effective when the person positively wants to get better. However, as anorexia is often associated with very complex emotional issues, recognising the underlying causes and learning to cope with them can be the most effective way to treat the illness. Specialist eating disorder helplines are available that can offer support and advice - see the Selected links and Support organisations sections of this article for more information.
Occasionally, a person with anorexia may become so weak that they require immediate hospitalisation. Where weight loss is so severe that there is an immediate threat to life, a doctor may use the Mental Health Act 1983 or Children Act 1989 to admit a person with anorexia to hospital against their wishes. Every effort is made to avoid this and it only happens in extreme circumstances. This is sometimes referred to as being sectioned, because a doctor will use a specific section of the Mental Health Act.
If someone is taken into hospital in this way, the hospital will manage their intake of food and fluids. This lack of control can be very distressing to someone with anorexia nervosa and will only be continued as long as healthcare professionals see it as the only way to prevent death.
Other illnesses that occur as a result of anorexia nervosa may need to be treated with medication. In some cases, antidepressant medication may be advised.
Women with anorexia may find it more difficult to become pregnant and are more likely to have premature or low birth-weight babies. For those who develop anorexia before or during puberty, it may delay some of the physical changes of puberty or lead to stunted growth.
Those with anorexia have an increased risk of developing osteoporosis later in life, and anorexia can make muscles - including the heart muscles - lose strength, leading to a greater risk of heart disease in later life.
Anorexia is a serious illness - there is between a 10% and 20% death rate. The most frequent causes of death associated with anorexia are starvation, dehydration, electrolyte (essential minerals in the blood) imbalance, infections, heart failure, and suicide.
The information shown here is Crown copyright and has been reproduced with the permission of NHS Direct. Last updated June 2007.