Anorexia nervosa: symptoms, causes, and treatments

last updated: Jun 01, 2021

5 min read

Poor body image is something most of us will deal with at some point in our lives, but just because it’s common, that doesn’t mean it’s harmless.

Body image affects both physical and mental health. A 2018 study found that over 77% of girls were unsatisfied with their bodies (Ganesan, 2018). Sometimes this dissatisfaction leads to unhealthy dieting and weight loss. In extreme cases, these behaviors can devolve into anorexia nervosa, a serious and life-threatening eating disorder.


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What is anorexia nervosa?

Anorexia nervosa, commonly shortened to anorexia, is an eating disorder defined by a severe restriction of calorie intake. It often leads to

  • Fear of gaining weight or obesity

  • Fear of foods or certain food groups

  • Underweight and extreme thinness

  • Inaccurate perception of current body weight

Anorexia is more common in young women and with certain occupations. Athletes, models, actors, and other careers that focus on physical performance and appearance often have more pressure to maintain unrealistically lean bodies. 

In sports that emphasize aesthetics, about 42% of female athletes experience an eating disorder (Sundgot-Borgen, 2004 ). 

While eating disorders are more common in some people, anyone is at risk regardless of sex, age, or culture. Anorexia is diagnosed using the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria (Substance, 2016):

  1. Restriction of energy intake leading to significantly low body weight and physical health

  2. Intense fear of gaining weight

  3. Disturbed by one’s body shape or weight, self-worth influenced by body weight, and lack of acknowledging severly low body weight.

Signs and symptoms of anorexia

Anorexia causes physical and emotional symptoms that affect a person's quality of life. Often, people aren’t diagnosed with anorexia until the physical signs of starvation are too dangerous to ignore.

Physical signs of anorexia

Physical signs of anorexia include (Moore, 2020):

  • Extreme thinness and low body weight

  • Extreme weight loss

  • Fatigue

  • Thinning hair

Some people with anorexia will also experience binging and purging, similar to people with bulimia nervosa or binge eating disorder. Purging behaviors include excessive exercise, self-induced vomiting, and the use of diuretics or laxatives. 

Behavioral signs of anorexia

Additional signs someone with anorexia may show include:

  • Preoccupation with food

  • Skipping meals or refusing to eat

  • Ignoring hunger and making excuses not to eat

  • Adopting rigid meal plans and food rules

  • Restricting multiple food groups

  • Not eating in public

  • Avoiding social events because of the food present

  • Frequently monitoring body image, repeatedly weighing self or measuring body

  • Complaining about being fat when they are not

  • Intense fear and guilt about food eaten

  • Covering up in layers of clothing to hide

  • Excessive exercise to make up for food eaten

  • Constipation

  • Irritability

  • Insomnia

  • Low self-esteem

  • Low libido or sex drive

  • Eroded teeth or calluses on hand from inducing vomiting

  • Cold intolerance

What causes anorexia?

The exact cause of anorexia is poorly understood. Even though it’s a disorder surrounding eating habits, the root of the problem is mental health. As with any condition affecting mental health, many factors likely play into its development. 

Some of the risk factors that may contribute to anorexia include (Moore, 2020):

  • Environment: In cultures that emphasize lean bodies, self-worth often becomes tied to the size of one’s body. Peer pressure and family history of dieting could increase the chances of developing an eating disorder.

  • Biology: Genetics and family history of eating disorders may increase the tendency for some people to develop an eating disorder. Any illness or injury affecting the brain and neurotransmitters could also increase eating disorder risk.

  • Psychology: Some people with eating disorders have obsessive-compulsive disorder, perfectionism traits, and depression. These other traits and conditions may make it more likely to develop an eating disorder. A family history of mental illnesses or mood disorders increases the risk for eating disorders.

Complications of anorexia

Anorexia leads to the prolonged lack of adequate calories and other essential vitamins and minerals. Inadequate nutrition can cause serious complications such as (Moore, 2020):

  • Delayed puberty

  • Infertility

  • Loss of period

  • Low blood pressure

  • Slowed heart rate

  • Osteoporosis

  • Low blood sugar

  • Low sodium levels

  • Insomnia

  • Swelling in arms and legs

  • Metabolic acidosis or alkalosis

  • Renal failure

  • Depression

When to see a healthcare provider

Some people with anorexia resist treatment or don’t see it as a problem. They may even view their desire for weight loss as a way to become healthier, at least at first. 

Over time, the signs of malnutrition become more apparent, and health complications begin. Seek medical attention if you are experiencing any of the following symptoms because it could be a sign of a serious medical complication. 

  • Dizziness or loss of consciousness

  • Changes in heart rate

  • Confusion

  • Weakness or fatigue

  • Loss of your period

You can find support for yourself or someone in your life who may have anorexia at the National Eating Disorders Association’s Helpline.

It can be challenging to take the first step to get treatment for anorexia. There are effective treatment options that can help you feel better, both physically and emotionally.

Treatment and support for anorexia

Anorexia is a serious physical and mental health condition best treated with the support of a team of experts. Dietitians, psychiatrists, and social workers trained in treating eating disorders support recovery from an eating disorder nutritionally, physically, and mentally.


Cognitive-behavioral therapy (CBT) is a type of psychotherapy that aims to improve coping skills, change beliefs, and encourage behavior changes. It focuses on changing thinking patterns that create challenges to help people better understand their behaviors and the challenges in their lives (Resmark, 2019).

CBT is an effective treatment used to help recover from anorexia because it can help change beliefs about body image and cope with returning to a normal weight.

A goal of treating anorexia is to help the person return to a healthy weight. While weight may be a goal for the healthcare team to track recovery, for the person with anorexia, weight is not the focus of treatment. Instead, the focus is often shifted towards improving health overall, such as increasing energy level, improving sleep, and regaining periods (in women of reproductive age). 

Psychotherapy can help to change the beliefs from controlling weight to balancing physical and emotional health. 

In teenagers, family-based psychotherapy is often recommended. Family therapy helps engage parents and other family members in the treatment plan (Moore, 2020). It aims to help add structure to the home environment to promote healthy eating behaviors and family meals. 

In the beginning, parents have full control over meal structure. As treatment continues, the teenager gradually becomes more involved in meal decisions to continue to grow a healthy relationship with food.


Some people don’t respond as quickly to therapy, so medications may be recommended. Olanzapine, also known as Zyprexa, is a commonly used medication for people who aren’t responding to treatment and to help with weight gain.

Other mental health conditions can occur along with anorexia, such as:

With these conditions, treatment plans often include a combination of medications (antidepressants, antianxiety medications, or antipsychotics) and therapy to help manage all symptoms. 


Without treatment, anorexia can lead to serious health complications and even become life-threatening. Hospitalization may be recommended for people experiencing low blood sugar, heart problems, and dehydration.

In severe cases, a person with anorexia may need a feeding tube to provide nutrition support at the beginning of their recovery. 

Electrolytes (such as potassium, sodium, phosphorus, and magnesium) are closely monitored when someone with severe anorexia begins eating or starts on a feeding tube. Electrolyte imbalances can be a sign of a condition called refeeding syndrome (Skowronska, 2019).  

Refeeding syndrome is the body’s response to nutrition when it has gone a long time without enough food intake. The body moves electrolytes around too quickly and causes dangerously low magnesium, phosphorus, and potassium levels. While refeeding syndrome can be dangerous, it is easily corrected with close monitoring and replacing electrolytes as needed (Skowronska, 2019).

Once people are medically stable, they are referred to inpatient psychiatry treatment or an outpatient treatment center. 

Anorexia prevention

Trained healthcare professionals may be able to spot the early warning signs of anorexia. Still, there is no guaranteed way to prevent it fully. 

Increasing coping skills, social support, and creating a healthy relationship with food and your body shape can help manage symptoms. These practices could also help to prevent new symptoms from developing or prevent a relapse of symptoms.

If you or a loved one is struggling with their relationship with food, body image, or may be experiencing anorexia, you can go to the National Eating Disorders Association’s Helpline for support.


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

  • Ganesan, S., Ravishankar, S. L., & Ramalingam, S. (2018). Are body image issues affecting our adolescents? A cross-sectional study among college going adolescent girls. Indian Journal of Community Medicine: Official Publication of Indian Association of Preventive & Social Medicine, 43 (Suppl 1), S42–S46. doi: 10.4103/ijcm.IJCM_62_18. Retrieved from

  • Moore CA, Bokor BR. (2021). Anorexia nervosa. StatPearls . Retrieved from

  • Skowrońska, A., Sójta, K., & Strzelecki, D. (2019). Refeeding syndrome as treatment complication of anorexia nervosa. Psychiatria Polska, 53 (5), 1113–1123. doi: 10.12740/PP/OnlineFirst/90275. Retrieved from

  • Substance Abuse and Mental Health Services Administration. (2016). DSM-5 changes: implications for child serious emotional disturbance. Retrieved from

  • Sundgot-Borgen, J., & Torstveit, M. K. (2004). Prevalence of eating disorders in elite athletes is higher than in the general population. Clinical Journal of Sport Medicine: Official Journal of the Canadian Academy of Sport Medicine, 14 (1), 25–32. doi: 10.1097/00042752-200401000-00005. Retrieved from

  • Resmark, G., Herpertz, S., Herpertz-Dahlmann, B., & Zeeck, A. (2019). Treatment of anorexia nervosa-new evidence-based guidelines. Journal of Clinical Medicine, 8 (2), 153. doi: 10.3390/jcm8020153. Retrieved from

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

June 01, 2021

Written by

Ashley Braun, RD, MPH

Fact checked by

Steve Silvestro, MD

About the medical reviewer

Dr. Steve Silvestro is a board-certified pediatrician and Associate Director, Clinical Content & Education at Ro.