Eating Disorders – Types, Symptoms, Effects, Complications

There are different types of eating disorders but most have one feature in common – the eating disorder is usually a manifestation of an underlying psychological problem. There is also some associated psychiatric features commonly present, such as depression, anxiety, low self-worth, personality disorder or substance misuse.

Disorders can range from severely reducing the amount of food eaten to apathy about maintaining a healthy diet, either by eating excessive or minute amounts of food. Apart from unhealthy or abnormal food and meal habits, there are other signs and symptoms of eating disorders that may be characteristic of or common among the different types of disorders.

nausea and vomiting

Types of Eating Disorders

Eating disorders are basically divided into three types :

  • Anorexia nervosa.
  • Bulimia nervosa.
  • Eating Disorders Not Otherwise Specified (EDNOS), which includes binge-eating disorder, compulsive overeating and other rare types of eating disorders.

Anorexia Nervosa

This is a type of eating disorder, commonly seen in adolescent girls, characterized by a compulsive need to control  the food intake. The criteria for defining anorexia nervosa includes :

  • Body weight less than 85% of the average ideal weight based on age, gender, race and body frame. A BMI of 17.5 or less is an important marker but this does not include every person who is severely underweight as other factors may be responsible in some cases.
  • A morbid fear of weight gain, even when severely underweight, leading to reduced food intake, induced vomiting or excessive exercising.
  • Perception of being ‘fat’ even when severely underweight, which may be linked to body dysmorphic disorder (BDD)
  • Amenorrhea (no period) for at least 3 successive menstrual cycles are absent, unless hormone contraceptives are being used.

Other Features of Anorexia Nervosa

  • Hormonal abnormalities are common, with low levels of luteinizing (in women) and thyroid hormones and increased levels of cortisol, leading to amenorrhea and osteoporosis.
  • Cardiac abnormalities, arrhythmias, dehydration and electrolyte imbalance, with low serum potassium, may occur due to frequent vomiting and laxative or diuretic misuse, and can ultimately lead to death.
  • Underlying psychological and psychiatric factors are usually present and intervention is necessary, either in the form of drug therapy and/or counseling.

Restoring nutritional balance, treating complications, and providing psychotherapy to resolve related issues comprise the basic approach to management of anorexia nervosa. There is a higher rate of suicide associated with anorexia nervosa when compared to other eating disorders and early intervention with professional supervision is crucial.

Eating disorders anorexia

Bulimia Nervosa

This type of eating disorder is common in young women. Although there is an obsession with controlling the body weight, it is usually associated with binge-eating (uncontrolled eating), followed by induced vomiting, laxative overuse, starvation or excessive exercise in an attempt to overcome the effects of binge-eating. This cycle may be constant or occur in episodes which can last for several times at a week.

Bulimics usually maintain a body weight within the normal BMI range (more than 17.5 ). Psychological problems are also common in bulimia nervosa and need to be addressed during treatment as there is a tendency to relapse.

Eating Disorders Not Otherwise Specified (EDNOS)

This includes binge-eating disorders, compulsive overeating and other rare types of eating disorders.

Binge-Eating Disorder

In this type of eating disorder, the person has recurrent episodes of uncontrolled overeating similar to bulimia. Although there are feelings of guilt or shame about their food consumption, there is no compulsion to ‘purge’ by  inducing vomiting, laxative or diuretic misuse, starvation or exercise. Being overweight or obese  is often a feature in binge-eating disorder and this further adds to the sense of poor self-worth or depression.

As with other eating disorders, psychological factors are often present. Therefore, in addition to medication like antidepressants, psychotherapy plays an important part in the treatment process. Binge-eating can lead to complications such as high cholesterol, diabetes, hypertension, and heart conditions.

Compulsive Overeating

The compulsive overeater has an uncontrolled obsession to eat large amounts of food even when not hungry. This often leads to binge-eating. Binge-eating disorder may be described as a type of compulsive overeating disorder although this compulsion is more episodic in binge-eating.


Some types of compulsive ‘over-eaters’ consume small amounts of food throughout the day while others will clearly overindulge at every meal. Depression, low-self esteem and mood swings are common in this eating disorder  Obesity is present in most cases, although there are instances where those suffering with compulsive overeating disorder will maintain a normal body weight.

Unusual Eating Habits and Rare Eating Disorders

There are other types of eating disorders which are rarely seen and this includes :


In this eating disorder there are cravings for inedible substances, such as sand, mud, chalk, plaster or glue.

Signs of disturbed behavior and low IQ may be present, especially in children. Nutritional deficiencies, a disrupted social environment and psychological illnesses could be the cause.

Pica is common in pregnant women but usually does not continue after childbirth. It is also seen in severe cases of iron-deficiency anemia and in both pregnancy and nutritional deficiencies, there is no indication of any psychological illness.

It can lead to complications such as lead poisoning, human intestinal worm infestations and malnutrition.

Prader-Willi Syndrome

This is a rare genetic condition where various physical and mental abnormalities are present. The eating disorder may be a result of an insatiable appetite which is due to a defect in the satiety center in the hypothalamus. This continuous need to eat may lead to the consumption of any edible substance, including pet food.

Night-Eating Syndrome

Anorexia in the morning, with a compulsion to eat in the evening hours or at night, and insomnia, are the typical features of this condition. Episodes of binge-eating may occur in the evening.

Sleep Eating Disorder

This condition is related to sleepwalking and binge-eating during this period, with no recollection of the events upon waking.

Orthorexia Nervosa

This condition relates to an obsession with eating only healthy foods or an abnormal fixation on the quality or health impact of the foods consumed. In orthorexia nervosa, the focus on researching foods as well as finding and preparing healthy meals reaches a point where it consumes a significant part of the person’s life. It can affect daily functioning and impact on social interaction.

Bigorexia (Muscle Dysmorphia)

This is another term for a condition where there is an obsession with the need to increase  the muscle mass. Typically a person suffering with this condition has a perception that they are not as muscular as they should be.  This perception, along with excessive exercising and food consumption (usually high protein foods),  interferes with the person’s work and social life.

Signs and Symptoms

The signs and symptoms of the different types of eating disorders may vary significantly, depending on the nature of the disorder. Since most eating disorders are linked to an underlying psychological disturbance, there is usually  common psychological features present in all of these disorders.

vomit tasting burps belching

Differentiating between the signs and symptoms of the eating disorder and that of any featuring psychological disorder will allow for a more conclusive diagnosis. The effects of different types of eating disorders may also assist with a final diagnosis.

Common Psychological Features of Eating Disorders

  • A sense of low self-worth is usually a common finding in most types of eating disorders and there is often a constant need for acceptance and approval from others.
  • A combination of anxiety, depression, personality disorders and obsessive compulsive features may also be present to varying degrees in the individual, irrespective of the eating disorder.
  • Substance abuse may be found in a person with an eating disorder and this does not only relate to alcohol, narcotic or nicotine abuse, but even the misuse of pharmaceutical drugs, both scheduled and OTC (over-the-counter).
  • A past history of obesity may often be present and this is usually the initiating factor for many types of eating disorders.
  • A tendency to be secretive, similar to drug and alcohol abusers, as well as a need to purge may be noticed.

In the three most common types of eating disorders, other features that may be evident (in addition to those above) include :

Anorexia Nervosa

Not all signs and symptoms mentioned below will be evident in a case of anorexia nervosa.

  • Obsession about the quantity and frequency of food intake with an excessive fear of gaining weight.
  • Tendency to measure and allocate exact (usually very small) portions of food during a meal and only eat certain types of food.
  • Being thin to the point of emaciation, yet the person is convinced that they are overweight or obese.
  • Change in usual apparel in order to hide the emaciation behind baggy, loose fitting clothing and hiding heavy objects in their clothing when being weighed on a scale.
  • Excessive or constant dieting with episodes of purging and a tendency to exercise excessively despite being underweight.
  • There may be some hyperactivity noticed in these individuals initially but as the condition progresses, abnormal fatigue and a reduced ability to concentrate may be noticed.
  • Amenorrhea (no period) for more than 3 months.
  • Altered mental and emotional state, change in the pattern of sleep, mood swings and tendency to withdraw socially.
  • Feeling of fullness after eating small meals and altered bowel movements, usually constipation.
  • Psychosexual problems.
  • Dental caries linked to poor nutrition and frequent episodes of vomiting.
  • Anemia.
  • Extreme sensitivity to cold.
  • Increase in the amount of lanugo hair (soft, fine type of body hair) on the arms and chest (hypertrichosis) and female facial hair (hirsutism).
  • Hypotension (low blood pressure) and bradycardia (slow pulse rate).
  • Electrolyte imbalance due to frequent binging and purging.
  • Hormonal imbalance – decreased estrogen, LH (luteinizing hormone), TSH (thyroid stimulating hormone) and increased blood levels of cortisol and the thyroid hormones, T3 (triiodothyronine) and T4 (thyroxine).
  • Difficulty falling pregnant or infertility.
  • Abnormal ECG – prolonged QT interval.
  • Arrhythmias – heart rate abnormalities.

Bulimia Nervosa

  • A normal body weight is usually maintained.
  • Episodes of binging followed by purging and severe dieting.
  • Tiredness and lethargy.
  • Constipation.
  • Feeling of fullness.
  • Abdominal pain.
  • Arrhythmias.
  • Irregular periods.
  • Swelling of the hands and feet.
  • GERD – gastro-esophageal reflux disease.
  • Erosion of dental enamel and dental caries.
  • Russell’s sign – calluses on the back of the hands, from tooth marks during induction of vomiting.
  • Electrolyte imbalance.
  • Abnormal ECG.
  • Severe dehydration.

Binge-Eating Disorder and Compulsive Overeating

  • Obesity is usually present although some compulsive over-eaters may maintain a normal body weight.
  • Feelings of guilt and shame after a binge but there is no attempt to induce vomiting or resort to other methods of purging, like laxative use.
  • Prefers to eat in isolation.
  • Relies heavily on food as a means of emotional support (‘comfort eating’).
  • Tendency to hide or store food for later consumption.
  • Other associated psychological problems, usually depression.
  • Fatigue.
  • Insomnia.

Effects of Eating Disorders

Eating disorders can lead to simple reversible complications such as anemia and irregular periods or eventually result in serious effects like heart failure or even result in death. The time period as to when these effects will occur cannot be predetermined. It is dependent on the individual’s constitution, severity of the eating disorder and as to when appropriate treatment is initiated.

While the signs and symptoms of the eating disorder will give an indication of the most likely complication that may arise soon, preventing these effects will depend on the level of care, patient compliance, past medical history and ability to recover.  It is important to note that even if the patient is undergoing treatment and there are promising signs of recovery, the complications associated with the different types of eating disorders can still occur even after treatment is initiated.


These complications can occur in the more common types of eating disorders, like anorexia nervosa, bulimia nervosa, binge-eating and compulsive over-eating disorders. Some of the complications may be isolated to cases of the rare types of eating disorders, like pica and muscle dysmorphia.

  • Anemia.
  • Amenorrhea (missed periods) and infertility as a result of hormonal imbalance.
  • Abdominal pain which may be a result of gastrointestinal conditions, liver and pancreas disorders.
  • Changes in bowel movements, usually constipation but also diarrhea may occur.
  • Brittle nails, dry skin and hair loss.
  • Brittle bones due to osteopenia and osteoporosis.
  • Cardiovascular complications like hypertension, arrhythmias, enlarged heart and heart failure.
  • Dehydration as a result of vomiting and diuretic or laxative misuse.
  • Diabetes which may be linked to obesity.
  • Death may occur due to a number of causes including kidney failure and cardiac complications.
  • Drug and alcohol abuse complications.
  • Gastrointestinal complications including peptic ulcers, gastroesophageal reflux disease (GERD), hiatal hernia, gastric dilatation and/or perforation.
  • High cholesterol linked to obesity.
  • Kidney failure.
  • Malnutrition.
  • Neurological complications like seizures, poor memory, impaired cognitive ability and peripheral neuropathy (pain, numbness and/or tingling) due to brain and/or nerve damage.
  • Parotid gland enlargement on both sides.
  • Shock.
  • Aggravation of already existing psychiatric problems with a tendency to become withdrawn and less sociable. This may result in the degradation of interpersonal relationships.
  • Side effects from anabolic steroid use, which is seen more often in males with bigorexia (muscle dysmorphia).
  • Pica, another form of eating disorder where a person craves for and eats non-food items (such as chalk, mud and various other things), can cause lead poisoning, human intestinal worm infestation, malnutrition, diarrhea and intestinal obstruction.

Eating disorders need to be recognized and diagnosed early so that the appropriate medical treatment and psychotherapy can be commenced. Immediate intervention will limit or even reverse some of the effects of eating disorders and with support and supervision during the recovery period, the chances of serious complications are drastically reduced.

Last updated on September 27, 2018.

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