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Anorexia nervosa

Anorexia nervosa is an eating disorder and mental health condition that can be life-threatening.

Anorexia nervosa is an eating disorder and mental health condition that can be life-threatening.

People with anorexia try to keep their weight as low as possible, usually by restricting the amount of food they eat. They often have a distorted image of themselves, thinking that they're fat when they're not.  

Some people with the condition also exercise excessively, and some eat a lot of food in a short space of time (binge eating) and then make themselves sick or use laxatives (purging).

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

Read more about the symptoms of anorexia nervosa.

As with other eating disorders, anorexia can be associated with depression, low self-esteem, alcohol misuse and self-harm.

Read more about the causes of anorexia nervosa.

Treating anorexia

If you have an eating disorder such as anorexia, the first step is to recognise you have a problem and visit your GP for a medical check up and advice on treatment.

One of the biggest challenges in treating anorexia is getting people with the condition to accept their behaviour is not normal. 

The first step towards getting better is to recognise the problem and to have a genuine desire to get well.

A combination of psychological treatments and advice on eating and nutrition usually helps to treat anorexia. More serious cases are treated in hospital or a specialist eating disorder clinic.

Read more about the treatment of anorexia nervosa.

Complications of anorexia

Not eating enough food can lead to a wide range of complications, some of which can be fatal, such as:

Read more about the complications of anorexia nervosa.


Once a person seeks help, it usually takes five to six years of treatment to fully recover, and relapses are common. Around half of people with anorexia will continue to have problems related to healthy eating despite treatment.

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

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Anorexia nervosa

The main symptom of anorexia is losing a lot of weight deliberately by eating as little as possible, making yourself vomit and doing too much exercise.

The main symptom of anorexia is losing a lot of weight deliberately.

For example, by:

  • eating as little as possible
  • making yourself vomit
  • over-exercising – burning more calories than you consume in a day

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

After eating they may try to get rid of food from their body by making themselves sick. Signs of regular vomiting could include:

  • leaving the table immediately after meals
  • dental problems such as tooth decay or bad breath caused by the acid in vomit damaging their teeth and mouth
  • hard skin on their knuckles, caused by putting their fingers down their throat

The need to obsessively burn calories usually draws people with anorexia to ‘high-impact’ activities, such as running, dancing or aerobics. Some people will use any available opportunity to burn calories, such as preferring to stand rather than sit.

They may try to make food pass through their body as quickly as possible. For example, by taking:

  • laxatives (medication that helps to empty the bowel)
  • diuretics (medication that helps remove fluid from the body)

In reality, laxatives and diuretics have little effect on calories absorbed from food.

Eating and food

Although anorexia means ‘loss of appetite’, people with anorexia nervosa do not usually lose their appetite – they like food and feel hungry.

However, they do not think about food in the same way as others. This is apparent in various ways. For example, they may:

  • tell lies about eating or what they have eaten
  • give excuses about why they are not eating
  • pretend they have eaten earlier
  • lie about how much weight they have lost
  • find it difficult to think about anything other than food
  • spend lots of time reading cookery books and recipes

Someone with anorexia nervosa strictly controls what they eat. For example, by:

  • strict dieting
  • counting the calories in food excessively
  • avoiding food they think is fattening
  • eating only low-calorie food
  • missing meals (fasting)
  • avoiding eating with other people
  • hiding food
  • cutting food into tiny pieces – to make it less obvious they have eaten little, and to make food easier to swallow
  • taking appetite suppressants, such as slimming or diet pills

They may also drink lots of fluids that contain caffeine, such as coffee, tea and low-calorie fizzy drinks, as these can provide a low-calorie, short-term burst of energy.

Some people with anorexia also use illegal stimulant drugs known to cause weight loss, such as cocaine or amphetamines.

Self-esteem, body image and feelings

People with anorexia often believe their value as a person is related to their weight and how they look. They think others will like them more if they are thinner, seeing their weight loss in a positive way.

They often have a distorted view of what they look like (their body image). For example, they think they look fat when they are not. They 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

Anorexic people usually have low self-esteem or self-confidence. They may withdraw from relationships and become distant from family and friends.

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

They may find concentration difficult, and might lose interest in their usual activities. They may have few interests, even though they seem busier than usual.

Other signs of anorexia

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

  • fine downy hair (lanugo) growing on their body
  • more hair on their face
  • their pubic hair becoming sparse and thin

Their heartbeat may be slow or irregular, which can lead to poor circulation. They may also:

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 other people of the same age.

Women and older girls with anorexia may stop having their periods (known as amenorrhoea or absent periods). Anorexia can also lead to infertility.

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Anorexia nervosa

There is no single cause for anorexia. Most experts think the condition is caused by a combination of psychological, environmental and biological factors.

There is no single cause for anorexia. Most experts believe the condition is caused by a combination of psychological, environmental and biological factors, which lead to a destructive cycle of behaviour.

It is widely accepted some people have distinct personality traits, making them more vulnerable to anorexia.

Environmental factors, such as going through puberty or living in a culture where being thin is an ideal, then causes the person to begin a pattern of long-term dieting and weight loss.

The lack of a normal diet has a biological effect on the brain, which helps reinforce the obsessive thinking and behaviour associated with anorexia.

A cycle then begins. The more the person diets, the greater its effect on the brain and the greater the desire to lose weight. This means that symptoms gradually, and then rapidly, get worse.

Each of these factors is explained in more detail below.

Psychological factors

Most people who develop anorexia share certain psychological factors that help define their personality and, to some extent, their behaviour. These include:

  • a tendency towards depression and anxiety
  • poor reaction to stress
  • excessive worrying and feeling scared or doubtful about the future
  • perfectionism – setting strict, demanding goals or standards
  • inhibition – where a person restrains or controls their behaviour and expression
  • feelings of obsession and compulsion (though not necessary ‘full-blown’ obsessive compulsive disorder) – an obsession is an unwanted thought, image or urge that repeatedly enters a person’s mind. A compulsion is a repetitive behaviour or mental act that a person feels compelled to perform.

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 also play a part. Girls (and, to a lesser extent, boys) are exposed to a wide range of different media which constantly reinforce the message that being thin is beautiful.

At the same time, magazines and newspapers focus on celebrities' minor physical imperfections, such as gaining a few pounds or having cellulite.

Other environmental factors that may contribute towards anorexia include:

Biological factors

Your brain requires a healthy, nutritious diet to function normally. It uses a fifth of all the calories you eat. So extreme dieting can disrupt normal functions of the brain, possibly making anorexia symptoms worse.

Malnutrition can also change the balance of hormones in the body, which can affect how the brain functions.

It is thought the change in hormones causes the brain to become sensitive to the effects of an amino acid called tryptophan, found in almost all types of food.

This sensitivity can cause feelings of anxiety in people with anorexia when they eat. At the same time, starving themselves and excessive exercise lowers levels of tryptophan, which may make the person feel calmer and more relaxed.

Another theory is that the system controlling a person’s sense of appetite becomes disrupted.

Appetite is controlled by a part of the brain called the hypothalamus. When your body needs more food, your hypothalamus releases chemicals to stimulate your appetite.

Once you have eaten enough food, hormones signal to your hypothalamus. Your hypothalamus will then release a different set of chemicals that essentially reward you for eating, and make you feel satisfied.

It is thought that this ‘appetite-reward pathway’ becomes scrambled in people with anorexia. The feeling of fullness after a meal does not produce a sense of reward, but a sense of anxiety, guilt or self-loathing. In turn, feeling hungry may help reduce these negative feelings.

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Anorexia nervosa

People with anorexia nervosa often do not seek help, probably because they are afraid. Many hide their condition for a long time, sometimes years.

People with anorexia nervosa do not often seek help, probably because they are afraid. Many hide their condition for a long time, sometimes years.

They usually find it difficult to admit they have a problem, or even talk about their symptoms. They will probably disagree they need to gain weight, and may not even realise anything is wrong.

If someone has anorexia, the most important step towards diagnosis and treatment is for them to:

  • recognise they need help
  • want to get better

However, to take this first step they may need lots of support and encouragement.

Helping yourself

If you have eating problems or think you may have anorexia, it is important to seek help as soon as possible. You could start by:

  • talking to someone you trust, such as one of your family or friends
  • asking them to go with you to see your GP

Helping someone else

If someone close to you is showing signs of anorexia, you may want to offer help and support.

You could try talking to the person about how they feel and encourage them to think about getting help. But try not to put pressure on them or be critical of them, as this could make things worse.

You may want to seek advice on how best you can help. For example, your GP or a support group can provide information on:

  • how to help the person recognise they have a problem
  • treatments available
  • how you can support them during their treatment

You could also offer to help by going with the person to see their GP. See treating anorexia nervosa for more information.

A leading charity for people with eating disorders is beat, which has a range of information on the help and support available for people with eating disorders, and their friends and families.

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Anorexia nervosa

Your GP will probably ask questions about your weight and eating habits. They may ask if you have lost weight recently and how you feel about your weight.

When making a diagnosis, 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 or quite quickly
  • how you feel about your weight, and if you are concerned about it
  • if you think you are overweight even though other people think you are thin
  • if you make yourself vomit regularly
  • (in women and girls) whether your periods have stopped and, if so, for how long

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 how serious your symptoms are.

Weight and BMI

Your GP may 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 normal BMI for adults is 20-25. People with anorexia generally have a BMI below 17.5.

For more information on BMI and health, see the BMI healthy weight calculator tool.

Blood tests and other tests

Your GP may not need to carry out any tests to diagnose anorexia nervosa, but they will probably check your pulse and blood pressure.

If you have anorexia, you have a higher risk of developing some heart conditions, such as irregular heartbeat (arrhythmia). Sometimes an ECG (electrocardiogram) may be needed to check how well your heart is working.

Your GP may do blood tests to check the level of:

  • fluids in your blood
  • chemicals or minerals, such as potassium in your blood – having abnormally low levels of potassium is a common complication of anorexia (read more about the complications of anorexia).

However, blood tests can sometimes give normal results in an anorexic person who is very thin and has a very low body weight.

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 – see treating anorexia for more information. Your GP will sometimes carry out this assessment themselves.

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Anorexia nervosa

Before your treatment begins, you will probably have an overall health assessment. This may be carried out by your GP or another healthcare professional.

If you are diagnosed with anorexia nervosa, your GP will probably be involved in your ongoing treatment and care.

Other healthcare professionals involved in your treatment may include a:

  • specialist counsellor
  • psychiatrist (doctor who specialises in treating mental health conditions)
  • psychologist
  • nurse
  • dietician (specialist in nutrition)
  • paediatrician (in cases of children and teenagers)

This group is known as your care team.

Your treatment plan

Where you are treated may depend on how severe your condition is. You may be treated as:

  • an outpatient (this is most common)
  • a day patient or in a day unit
  • an inpatient in hospital or specialist centre, if your weight loss or symptoms are severe

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

Treatment for anorexia usually includes:

  • psychological treatment  talking to a therapist or counsellor
  • advice about eating and nutrition to help you gain weight safely

These treatments work better when combined, rather than on their own.

Your physical health will be monitored closely during your treatment. Your weight will be checked regularly and you will also have regular health checks. In children and young people, their height will also be regularly checked.

Other health problems caused by your anorexia will also be treated. For example:

  • if you vomit regularly, you will be given dental hygiene advice to help prevent stomach acid damaging the enamel on your teeth; you will also be advised to visit a dentist regularly
  • if you take laxatives or diuretics, you will be advised to reduce them gradually so your body can adjust; stopping them suddenly can cause problems, such as feeling sick and constipation

Gaining weight safely

You will be given advice about how to increase the amount you eat so you can gain weight safely, ensuring you receive the vitamins and nutrients you need.

You will be encouraged to eat small amounts of food and gradually increase what you eat as your body will not be used to dealing with normal amounts. The aim is to have a regular eating pattern, with three meals a day.

You may also need to take supplements to adjust the chemical balance in your body.

If you are treated as an outpatient, the aim will be to gain an average of 0.5kg a week to avoid complications associated with gaining weight more quickly, such as a chemical imbalance in your body.

If your weight loss is severe, you may be admitted to hospital. This is known as ‘re-feeding’. People treated as inpatients should aim to gain an average of around 0.5-1.0kg (1-2lbs) a week.

For more information, see ‘How can I gain weight safely’and treating malnutrition.

Types of psychological treatment

A range of psychological treatments are used to treat anorexia, such as:

  • cognitive analytic therapy (CAT)
  • cognitive behavioural therapy (CBT)
  • interpersonal therapy (IPT)
  • focal psychodynamic therapy (FPT)
  • family therapy

These are discussed below.

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 events in your past that explain why the unhealthy patterns developed
  • recognition  admitting how these patterns are contributing towards your anorexia
  • revision  identifying changes you can make to 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. In turn, our actions can affect how we think and feel.

The therapist will show you how the symptoms of anorexia are 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 you to adopt healthier, more realistic ways of thinking that should lead to more positive behaviour.

Read more about cognitive behavioural therapy.

Interpersonal therapy (IPT)

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

Anorexia may be associated with feelings of low self-esteem, anxiety and 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, being re-acted in adult life.

FPT encourages you to think about how early childhood experiences may have affected you. You may then be able to find more successful ways of coping with stressful situations and negative thoughts and emotions.

Family therapy

Anorexia does not just impact on one individual; it can have a big impact on the whole family.

Family therapy involves the family discussing how anorexia has affected them.


Medication alone is not usually effective in treating anorexia. It is usually only used to treat associated symptoms, such as obsessive compulsive disorder (OCD) or depression.

Medication will usually be recommended in combination with psychological or nutritional treatments.

Selective serotonin reuptake inhibitors

The selective serotonin reuptake inhibitors (SSRIs) type of antidepressants are usually recommended to treat mood disorders such as depression or OCD.

However, due to the risk of complications, SSRIs can only be used in people who have gained at least 85% of their recommended weight.

SSRIs are not usually recommended for children under 18 years of age.

Common side effects of SSRIs include:

  • feeling sick
  • blurred vision
  • diarrhoea or constipation
  • dizziness 
  • feeling agitated or shaky

These side effects should improve over time, although some can occasionally persist.


A medication called olanzapine may be useful in treating anorexia in people who do not respond to other treatments.

Olanzapine was originally designed to treat psychosis but has been found to be helpful in reducing a person’s anxiety around issues such as weight and diet.

Side effects of olanzapine include:

  • sleepiness
  • dizziness
  • muscle stiffness or spasms
  • constipation
  • dry mouth
  • rash

Compulsory treatment

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

In this situation, 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’.

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Anorexia nervosa

Complications of anorexia nervosa include low blood pressure, kidney failure and heart disease.

If anorexia nervosa is not treated, the condition can lead to severe health problems.

If treatment is not working or your condition deteriorates, you may be admitted to hospital.

It's also quite common for anorexia to return after treatment for example, if a woman tries to lose weight gained during pregnancy.

Other health problems

Long-term anorexia can lead to severe complications and health problems which can be permanent, such as damaged bones.

People with anorexia also have an increased risk of:

  • poor circulation and cardiovascular problems
  • heart conditions, such as coronary heart disease and irregular heartbeat (arrhythmia)

Anorexia can lead to another eating disorder called bulimia nervosa, where the person binge eats, then immediately makes themselves sick or uses laxatives to rid their body of the food.

Anorexia can also cause an imbalance of minerals in the blood, such as potassium, calcium and sodium.  These minerals play an important part in keeping you healthy.

A low level of potassium (hypokalaemia), can cause:

  • tiredness
  • weakness
  • dehydration 
  • kidney damage
  • seizures (fits)
  • irregular heartbeat (arrhythmia)

Low levels of calcium can cause muscle spasms, a lack of calcium and vitamin D can cause bone damage and a lack of sodium (hyponatraemia) can cause confusion and fits.

Other complications of anorexia include:

Misusing laxatives can permanently damage the bowels and cause permanent constipation.

Anorexia and pregnancy

If you have anorexia and are pregnant, you will be monitored closely. You may need extra health checks as part of your antenatal and postnatal care.

Anorexia during pregnancy can increase the risk of complications, such as

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

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Anorexia nervosa

Katie Metcalfe, now 21, had anorexia from the age of 14 to 19. She shares her experiences of life with anorexia.

Katie Metcalfe, 21, is starting a creative writing degree at Cumbria University, but seven years ago her life was very different.

"My battle with anorexia started when I was 14. My situation at the time was unusual: I was at a Rudolph Steiner school in Botton Village, near Whitby, in a class with three other boys. The pressure of being the only girl with hormone-raging teenagers was enormous. I had no self-confidence, and my body became a focus of paranoia.

"Stress in my life multiplied when my parents told me there was trouble in their marriage. In addition, we were about to move house.

"Nothing in my life seemed to be right. I started to think that perhaps if I lost some weight and improved my fitness, things would change for the better. I assumed that thin people had fantastic lives and I could too.

"I made a New Year’s resolution to go on a diet, so I began to restrict my eating. I cut out fats, carbs and dairy, and lived on rice cakes, apples and lettuce.

"As I began to lose weight I started to feel that life was worth living. At last I seemed to be achieving something. A voice began to whisper in my ear, and as I lost more weight, it became louder. Eventually, it was all I could hear. Nothing mattered more than satisfying the voice’s need for weight loss and, ultimately, perfection.

"My weight dropped from 8.5st to under 5st. My hair fell out, my skin cracked and bled, my bones ached and my periods stopped. I was also cycling between 13km (eight miles) and 24km (15 miles) a day to satisfy anorexia’s need for exercise. But I still didn’t believe I was thin enough. When I looked in the mirror, a mound of blubber stared back.

"My mum took me to the GP when my periods stopped, but they sent me home with a diet sheet, which said I must try to eat more.

"Eventually, I collapsed and ended up in hospital after having a minor heart attack while riding my bike. I was kept on a heart monitor for two days. I was sent home with another diet plan and the simple instruction: ‘eat’.

"Eventually, my GP realised I needed help. I was admitted to a psychiatric ward in a hospital in Middlesbrough, where I stayed for the next nine months.

"I was put on bed-rest for five months. My treatment involved cognitive therapy sessions once a week, and I gradually started to eat small amounts of food again. My recovery was slow. What really helped to pull me through was writing, and the consistent support from my family.

"I started to write about my experiences and realised that I wanted to recover so I could help others who were battling with the same problem. I gradually got better and went back home the day before my 16th birthday.

"I have had a couple of relapses, but five years on I am fully recovered, with few long-lasting effects. Although I have been diagnosed with the early stage of osteoporosis, my periods have come back, so I can have children.

"I still feel depressed at times but writing about it helps me get over it. I eat healthily and exercise for pleasure, not punishment. My book, A Stranger in the Family (Accent Press), has been published and I'm about to start a university degree. A few years ago I would never have imagined that.

"If you're going through what I went through, you must talk about how you are feeling to your parents, friends or doctor, no matter how insignificant you believe your issue might be. It's vital to express depressive feelings because things only get worse if you bottle them up, and this can lead to major health problems.

"Aim to live every day as though it is your last and not submit to anorexia. Try to defeat anorexia before it defeats you. Always remember that help is out there."

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