Eating disorders – Anorexia nervosa


Eating disorders – Anorexia nervosa


Anorexia nervosa is a serious mental health condition. It is aneating disorder in which people keep their body weight as low as possible.

People with anorexia usually do this by restricting the amount of food they eat, making themselves vomit and exercising excessively. 

The condition often develops out of an anxiety about body shape and weight that originates from a fear of being fat or a desire to be thin. Many people with anorexia have a distorted image of themselves, thinking that they're fat when they're not.

Anorexia most commonly affects girls and women, although it has become more common in boys and men in recent years. On average, the condition first develops at around the age of 16 to 17.

Signs and symptoms of anorexia

People with anorexia often go to great lengths to hide their behaviour from family and friends by lying about what they have eaten, or by pretending to have eaten earlier.

Signs that someone may have anorexia or another eating disorderinclude:

missing meals, eating very little or avoiding eating any fatty foods

obsessively counting calories in food 

leaving the table immediately after eating so they can vomit

taking appetite suppressants, laxatives or diuretics (medication that helps remove fluid from the body)

repeatedly weighing themselves or checking their body in the mirror

physical problems, such as feeling lightheaded or dizzy, hair lossor dry skin

Anorexia can also be associated with other psychological problems such as depression, anxiety, low self-esteem, alcohol misuse and self-harm.

Getting help

People with anorexia often don't seek help, perhaps because they're afraid or don't recognise they have a problem. Many have hidden their condition for a long time – sometimes years.

The most important first step is for someone with anorexia to realise that they need help and want to get better.

If you suspect someone you know has anorexia, you should try to talk to them about your worries and encourage them to seek help.

This can be a very difficult conversation because they may be defensive and refuse to accept they have a problem. But it's important not to criticise or pressure them as this can make things worse.

You may want to seek advice from an eating disorder support group such as Beat on how best to broach the subject.

If you think you may have anorexia, try to seek help as soon as possible. You could start by talking to someone you trust, such as someone in your family or a friend, and perhaps ask them to go with you to see your GP.

Treating anorexia

Before anorexia can be treated, a physical, psychological and social needs assessment will need to be carried out by the GP or an eating disorders specialist to help determine the most suitable care plan.

In most cases, treatment will involve a combination of psychological therapy and individually tailored advice on eating and nutrition to help you gain weight safely.

A range of different healthcare professionals will usually be involved in your care, such as GPs, psychiatrists, specialist nurses and dietitians.

Most people are able to be treated on an outpatient basis, which means you can go home between appointments. More serious cases are treated in hospital or specialist eating disorder clinics.


It can take several years of treatment to fully recover from anorexia and relapses are common. For example, a woman may relapse if she tries to lose weight gained during pregnancy.

Around half of people with anorexia will continue to have some level of eating problem despite treatment.

If anorexia remains unsuccessfully treated for a long time, a number of serious further problems can develop. These can include fragile bones (osteoporosis), infertility, an irregular heartbeat and other heart problems.

Despite being an uncommon condition, anorexia is one of the leading causes of mental health-related deaths. This can be because of the effects of malnutrition or as a result of suicide.


Symptoms of anorexia 

The main symptom of anorexia is deliberately losing a lot of weight, although there are often a number of other physical and psychological signs of a problem.

Intentional weight loss

A person with anorexia will want to weigh as little as possible – much less than is healthy for their age and height. They are so afraid of gaining weight they cannot eat normally.

In an attempt to lose weight, they may:

miss meals, eat very little or avoid eating any fatty foods

lie about what and when they've eaten

obsessively count the calories in food 

lie about how much they weigh

exercise excessively

take appetite suppressants, such as slimming or diet pills

make themselves vomit – you may notice they leave the table immediately after meals or have dental problems such as tooth decay or bad breath caused by the acid in vomit

They may also take laxatives or diuretics (medication that helps remove fluid from the body), although in reality these have little effect on calories absorbed from food.

Self-esteem, body image and feelings

People with anorexia often believe their value as a person hinges on their weight and how they look. They may think others will like them more or they will feel happier if they are thinner and see their excessive weight loss in a positive way.

They often have a distorted view of what they look like, thinking they look fat when they are not.

Others may try to hide how thin they are by wearing loose or baggy clothes.

Many people also practise a type of behaviour known as "body checking", which involves persistently and repeatedly:

weighing themselves

measuring themselves, such as their waist size

checking their body in the mirror

People with anorexia also usually have low self-esteem or self-confidence. They may withdraw from relationships, become distant from family and friends, and lose interest in activities they previously enjoyed.

Anorexia can also affect the person's school work or how well they perform their job.

Other signs of anorexia

Eating too little for a long time can also result in physical symptoms, such as:

bloating or constipation


feeling lightheaded or dizzy

feeling very tired 

feeling cold

discoloured hands and feet caused by poor circulation

dry skin

hair loss from the scalp

abdominal pain

problems sleeping

fine downy hair (lanugo) growing on the body

brittle nails

In children with anorexia, puberty and the associated growth spurt may be delayed. They may gain less weight than expected – if any – and may be smaller than others of the same age.

Women and older girls with anorexia may stop having their periods (known as amenorrhoea, or absent periods).


Causes of anorexia 

The exact causes of anorexia nervosa are unclear, although most specialists believe it is likely to be the result of a combination of factors

Psychological factors

Many people who develop anorexia share certain personality and behavioural traits that may make them more likely to develop the condition. These include:

a tendency towards depression and anxiety

finding it hard to handle stress

excessive worrying and feeling scared or doubtful about the future

perfectionism – setting strict, demanding goals or standards

being very emotionally restrained

having feelings of obsession and compulsion (but not necessarilyobsessive compulsive disorder) – unwanted thoughts, images or urges that compel them to perform certain acts

It has also been suggested that some people with anorexia have an overwhelming fear (phobia) of being fat.

Environmental factors

Puberty seems to be an important environmental factor contributing to anorexia. It may be the combination of hormonal changes and feelings of stress, anxiety and low self-esteem during puberty that triggers anorexia.

Western culture and society may also play a part. Girls – and, to a lesser extent, boys – are exposed to a wide range of media messages that constantly reinforce the idea that being thin is beautiful.

Magazines and newspapers also focus on celebrities' minor physical imperfections, such as gaining a few pounds or having cellulite.

Other environmental factors that may contribute towards anorexia include:

pressures and stress at school, such as exams or bullying, particularly teasing about body weight or shape

occupations or hobbies where being thin is seen as the ideal, such as dancing or athletics

a stressful life event, such as losing a job, the breakdown of a relationship or bereavement

difficult family relationships

physical or sexual abuse

Anorexia often starts off as a form of dieting that gradually gets out of control.

Biological and genetic factors

It has been suggested that changes in brain function or hormone levels may also have a role in anorexia, although it is not clear if these lead to anorexia or if they develop later as a result of malnutrition.

These changes may affect the part of the brain that controls appetite, or they may lead to feelings of anxiety and guilt when eating that improve when meals are missed or after excessive exercise.

The risk of someone developing anorexia is also thought to be greater in people with a family history of eating disorders, depression or substance misuse, which suggests genes could play a role.

Diagnosing anorexia 

When trying to determine if you have an eating disorder, your GP will probably ask questions about your weight and eating habits.

For example, they may ask:

if you have lost a lot of weight recently

how you feel about your weight and if you are concerned about it

if you make yourself vomit regularly

(in women and girls) whether your periods have stopped and, if so, for how long

if you think you have an eating problem

It is important to answer these questions honestly. Your GP is not trying to judge you or "catch you out". They just need to accurately assess your condition.

Weight and BMI

Your GP will usually check your weight. If someone has anorexia nervosa, their weight is generally at least 15% below average for their age, sex and height.

Your GP may also calculate your body mass index (BMI). A healthy BMI for adults is 18.5 to 24.9, although in some cases doctors may be concerned if you have a BMI below 20. Adults with anorexia generally have a BMI below 17.5.

The normal BMI for young people depends on their age, so it may need to be plotted on a special chart.

Other tests

Your GP may not need to carry out any tests to diagnose anorexia nervosa, but they may check your pulse and blood pressure, take your temperature and examine your hands and feet to see if you have signs of any complications of anorexia.

Your GP may also ask you to carry out some simple physical exercises, such as moving between sitting, squatting and standing, to assess your muscle strength.

If you have anorexia, you have a higher risk of developing some heart conditions, such as an irregular heartbeat (arrhythmia). Sometimes an ECG (electrocardiogram) may be needed. This is where a number of electrodes (small, sticky patches) are put on your arms, legs and chest to record the electrical signals produced by your heart.

Your GP may also perform blood tests to check your general health and the levels of chemicals or minerals such as potassium.

Referral to a specialist

If your GP thinks you may have anorexia, they may refer you to a specialist in eating disorders for a more detailed assessment and treatment, although your GP will sometimes carry out this assessment themselves.

Media last reviewed: 31/10/2013
Next review due: 31/10/2015

Page last reviewed: 16/04/2014

Next review due: 16/04/2016


Treating anorexia

The treatment for anorexia nervosa usually involves a combination of psychological therapy and supervised weight gain.

It is important to start treatment as early as possible, particularly if someone has already lost a lot of weight, to reduce the risk of seriouscomplications of anorexia.

The treatment plan

GPs will normally be closely involved in ongoing treatment, although other healthcare professionals are usually involved, including:

specialist counsellors



specialist nurses


paediatricians – in cases affecting children and teenagers 

Before treatment starts, members of this multidisciplinary care team will carry out a detailed physical, psychological and social needs assessment and develop a care plan.

Most people are treated as an outpatient, which means they visit hospitals, specialist centres or individual members of their care team for appointments, but return home in between.

In more severe cases, people may need to stay in hospital or a specialist centre for longer periods during the day (day patient) or may need to be admitted as an inpatient.

Psychological treatment

A number of different psychological treatments can be used to treat anorexia. Depending on the severity of the condition, treatment will be for at least 6 to 12 months or more.

Cognitive analytic therapy (CAT)

CAT is based on the theory that mental health conditions such as anorexia are caused by unhealthy patterns of behaviour and thinking developed in the past, usually during childhood.

CAT involves a three-stage process:

reformulation – looking for past events that may explain why the unhealthy patterns developed

recognition – helping people see how these patterns are contributing towards the anorexia

revision – identifying changes that can break these unhealthy patterns


Cognitive behavioural therapy (CBT)

CBT is based on the theory that how we think about a situation affects how we act and that, in turn, our actions can affect how we think and feel.

In anorexia, the therapist will attempt to show how anorexia is often associated with unhealthy and unrealistic thoughts and beliefs regarding food and diet. For example, thinking that:

"putting on weight is the single worst thing that can happen in my life"

"everyone I know secretly thinks I am fat"

"if I finish the whole meal then people I am eating with will think I am greedy and worthless"

The therapist will encourage the adoption of healthier, more realistic ways of thinking that should lead to more positive behaviour.


Interpersonal therapy (IPT)

IPT is based on the theory that relationships with other people and the outside world in general have a powerful effect on mental health.

Anorexia may be associated with feelings of low self-esteem, anxietyand self-doubt caused by problems with interacting with people.

During IPT, the therapist will explore negative issues associated with your interpersonal relationships and how these issues can be resolved.


Focal psychodynamic therapy (FPT)

FPT is based on the theory that mental health conditions may be associated with unresolved conflicts that occurred in the past, usually in childhood.

The therapy encourages people with anorexia to think about how early childhood experiences may have affected them. The aim is to find more successful ways of coping with stressful situations and negative thoughts and emotions.


Family interventions

Anorexia does not just impact on one individual. It can have a big impact on the whole family. Family interventions are an important part of treatment for young people with anorexia.

Family interventions should focus on the eating disorder. They involve the family discussing how anorexia has affected them. They also help the family understand the condition and how they can help.


Gaining weight safely

The care plan will include advice about how to increase the amount eaten so weight is gained safely.

Physical health – as well as weight – is monitored closely. The height of children and young people will also be regularly checked to make sure they are developing as expected.

Only small amounts of food will be expected to be eaten at first, gradually increasing as the body becomes used to dealing with normal amounts.

The eventual aim is to have a regular eating pattern, with three meals a day, possibly with vitamin and mineral supplements.

An outpatient target is an average gain of 0.5kg a week. In a specialist unit, the aim will usually be to gain an average of around 0.5-1.0kg a week.

See treating malnutrition for more information about what gaining weight at home or in hospital may involve.


Compulsory treatment

Occasionally, someone with anorexia may refuse treatment even though they are severely ill and their life is at risk.

As a last resort in these cases, doctors may decide to admit the person to hospital for compulsory treatment under the Mental Health Act. This is sometimes known as "sectioning" or being "sectioned".


Treating additional problems

In addition to the main treatments mentioned above, other health problems caused by your anorexia will also need to be treated.

If you make yourself vomit regularly, you will be given dental hygieneadvice to help prevent stomach acid damaging the enamel on your teeth.

For example, you may be advised to not brush your teeth soon after vomiting to avoid further abrasion to tooth enamel and to rinse out your mouth with water instead.

You may also be told to avoid acidic foods and mouth washes. You will also be advised to visit a dentist regularly so they can check for any problems.

If you have been taking laxatives or diuretics in an attempt to lose weight, you will be advised to reduce them gradually so your body can adjust. This is because stopping them suddenly can cause problems such as nausea and constipation.



Medication alone is not usually effective in treating anorexia. It is usually only used in combination with the measures mentioned above to treat associated psychological problems, such as obsessive compulsive disorder (OCD) or depression.

Two of the main types of medication used in people with anorexia are:

selective serotonin reuptake inhibitors (SSRIs) – a type of antidepressant medication that can help people with co-existing psychological problems such as depression and anxiety

olanzapine – a medication that can help reduce feelings of anxiety related to issues such as weight and diet in people who have not responded to other treatments

SSRIs tend to be avoided until you have started to gain weight as the risk of more serious side effects is increased in people who are severely underweight. They are only used cautiously in young people under 18.


Complications of anorexia  

If anorexia nervosa is not treated, the condition can lead to a number of serious health problems.

In some cases, the condition can even be fatal.


Other health problems

Long-term anorexia can lead to severe complications and health problems, often as a result of malnutrition. Some of these may improve as the condition is treated, but others can be permanent.

Health problems associated with anorexia include:

problems with muscles and bones – including weakness, fragile bones (osteoporosis) and problems with physical development in children and young adults

sexual problems – including absent periods and infertility in women, and loss of sex drive and erectile dysfunction in men

problems with the heart and blood vessels – including poor circulation, an irregular heartbeat, low blood pressure, heart valve disease, heart failure and swelling in the feet, hands or face (oedema)

problems with the brain and nerves – including seizures (fits) and difficulties with concentration and memory

other problems – kidney damage, liver damage, anaemia and low blood sugar (hypoglycaemia)

Some people with anorexia can go on to develop another eating disorder called bulimia nervosa. This is where a person binge eats then immediately makes themselves sick or uses laxatives to rid their body of the food.

Pregnancy complications

If you have anorexia and are pregnant, you will need to be monitored closely during pregnancy and after you have given birth.

Anorexia during pregnancy can increase the risk of problems such as:


giving birth early (premature birth)

having a baby with a low birth weight

needing a caesarean section

You are also likely to need extra care and support during pregnancy if you have previously had anorexia and recovered from it.