Eating disorders

Eating disorders refer to unhealthy eating habits, which cause psychological and physical damage but can be treated in many cases.

Alternative names for eating disorders

Anorexia nervosa; bulimia nervosa; binge-eating disorder; eating disorder – not otherwise specified

What are eating disorders?

Weight management is important for people with eating disorders.

Weight management is important for people with eating disorders.

Many eating styles can help us to stay healthy, but some are driven by an intense fear of becoming fat. These can damage our health and are called eating disorders. The two most common problems are anorexia nervosa and bulimia nervosa. They are described separately here, but the symptoms are often mixed.

What causes eating disorders?

There is no simple answer, but these ideas have all been suggested as explanations:

  • Social pressure – communities or social groups that do not value thinness have fewer people with an eating disorder. Places where thinness is valued, such as ballet schools or the modelling industry, have more people with an eating disorder. The media show pictures of idealised, artificially slim people and, as a result, many of us feel the need to diet. Most of us can only diet so much before our body tells us that it is time to start eating again. Some people with anorexia may not have this same body ‘switch’ and can keep their body weight dangerously low for a long time. Other people may starve themselves until they feel so hungry, they eat a lot of food at once. They then compensate for this by excessive exercise, vomiting or laxative use. This makes them hungry again and they become stuck in a bulimic cycle.
  • Control – it can be very satisfying to diet. It may be that our weight is the only part of our life over which we feel we have some control.
  • Puberty – anorexia can reverse some of the physical changes of becoming an adult, such as pubic and facial hair in men and breasts and menstrual periods in women. This may help to put off the demands of getting older, particularly sexual ones.
  • Family – eating is an important part of our social lives with other people. Accepting food gives pleasure and refusing it will often upset others. This is particularly true within families. Saying ‘no’ to food may be the only way some people can express their feelings or have any say or control within the family.
  • Depression – we often eat when we are upset. People with bulimia are often depressed, and it may be that binges start off as a way of coping with feelings of unhappiness. Likewise, people with anorexia and bulimia often have a low opinion of themselves and compare themselves unfavourably to other people.
  • Emotional distress – we all react differently when bad things happen or when our lives change.

Anorexia and bulimia have been related to a number of additional factors including:

  • life difficulties
  • sexual abuse
  • physical illness
  • upsetting events
  • important events.

What are the signs and symptoms of an eating disorder?

The signs and symptoms differ depending on which eating disorder the person has.

For anorexia nervosa, common symptoms include:

  • worrying more and more about our weight
  • eating less
  • exercising more
  • being unable to stop losing weight, even when we are below a safe weight
  • losing interest in sex
  • in women, periods become irregular or stop. In men and boys, erections and wet dreams stop and testicles shrink.

For bulimia nervosa, common symptoms include:

  • worrying more about our weight (we may be at a normal weight)
  • binge-eating
  • causing vomiting and/or using laxatives
  • irregular periods in women.

How common are eating disorders?

About 1 in 250 women and 1 in 2,000 men will experience anorexia, generally starting in adolescence or early adulthood. About five times that number will suffer from bulimia, which usually occurs at a slightly later stage.

Are eating disorders inherited?

While this is not clear, people are more likely to have an eating disorder if a brother, sister or parent has an eating disorder. However, this may be due to a person learning from their relative’s unhealthy attitudes about food, rather than a genetic link.

How are eating disorders diagnosed?

Most eating disorders are diagnosed by GPs after a clinical interview and measurement of height and weight. People might choose to visit their doctor because of eating difficulties, attend with concerned relatives, or attend with other complaints seemingly unrelated to eating. Some people may visit hospital with the physical complications of malnutrition and be referred directly to specialist services.

What hormonal changes occur?

The hormonal changes in anorexia occur as a result of malnutrition. These include a fall in the concentration of sex hormones and thyroid hormones. These hormone levels return to normal when patients reach a normal weight. It is unusual for hormonal therapies to be used although some patients are prescribed oestrogen (women) or testosterone (men) until their anorexia is treated (by other means). These hormonal treatments do not treat the anorexia, but they might protect the bones from osteoporosis to some extent while doctors are treating the anorexia.

How are eating disorders treated?

Eating disorders can be treated either by self-help or professional help. The type of treatment that is appropriate depends on the severity of the disorder, with more severe conditions needing professional help.

Bulimia can be tackled using a self-help manual combined with guidance from a therapist. Anorexia usually needs help from a clinic or therapist. Self-help involves:

  • trying to stick to regular mealtimes – breakfast, lunch and dinner. If body weight is very low, they should have extra snacks.
  • keeping a diary of what is eaten, thoughts and feelings. This can be used to see if there are links between feelings, thoughts and what is eaten.

The GP can refer the patient to a specialist counsellor, psychiatrist or psychologist. The eating disorder may have caused physical problems and a physical health check is advisable. The physical consequences of eating disorders may require additional treatment.

There is a range of specific treatments for anorexia including:

  • Psychiatric support – a specialist will want to find out when the problem started and how it developed. The patient will be weighed and, depending on how much weight has been lost, may need a physical examination and blood tests.
  • Psychotherapy or counselling – this involves talking to a therapist about thoughts and feelings. It can help to understand how the problem started and how a person can change some of the ways they think and feel about things.
  • Eating advice – a dietician may discuss healthy eating. Vitamin supplements may be needed.
  • Hospital admission – this is only an option if the patient is dangerously underweight or their condition is not improving. It involves controlling eating, carrying out physical checks and talking about thoughts and feelings.

Specific treatments for bulimia nervosa include:

  • Cognitive behavioural therapy – this can be done with a therapist, with a self-help book, in group sessions, or with a computer program. Cognitive behavioural therapy helps the patient to look at the links between thoughts, feelings and actions.
  • Eating advice – this helps the patient to get back to regular eating, without starving or vomiting.
  • Medication – antidepressants can reduce the urge to binge. Unfortunately, without the other forms of help, the benefits wear off after a while.

What are the longer-term implications of eating disorders?

Without treatment, most serious eating disorders will get worse over time. Most people with a serious eating disorder will end up having some sort of treatment. Although treatment usually carries on for a long time, many people do recover from the eating disorder. Ultimately, an eating disorder can cause death, but this is less likely to happen in people who do not vomit, use laxatives and drink alcohol.

An eating disorder can also cause other long-term changes to the body including an increased risk of developing osteoporosis, problems with dental health relating to tooth decay and problems related to fertility.

Last reviewed: Dec 2016