The back of a person with<unk> <unk>  is an eating disorder characterized by attempts to lose weight to the point of starvation. A person with<unk>  may exhibit a number of signs and symptoms, the type and severity of which may vary and be present but not readily apparent.<unk> , and the associated malnutrition that results from self-imposed starvation, can cause complications in every major organ system in the body. Hypokalaemia, a drop in the level of potassium in the blood, is a sign of<unk> . A significant drop in potassium can cause abnormal heart rhythms, constipation, fatigue, muscle damage, and paralysis. Signs and symptoms may be classified in physical, cognitive, affective, behavioral and perceptual: Physical symptoms * A low body mass index for one's age and height * Amenorrhea, a symptom that occurs after prolonged weight loss, causing menstruation to stop *Dry hair and skin, as well as hair thinning * Fear of even the slightest weight gain; taking all precautionary measures to avoid weight gain or becoming "overweight" * Rapid, continuous weight loss * Lanugo: soft, fine hair growing over the face and body *Bradycardia or tachycardia. *Chronic fatigue *Orange discoloration of the skin, particularly the feet (Carotenosis) *Infertility *Halitosis (from vomiting or starvation-induced ketosis) *Hypotension or orthostatic hypotension *Having severe muscle tension, aches and pains *Insomnia *Abdominal distension Cognitive symptoms * An obsession with counting calories and monitoring fat contents of food. * Preoccupation with food, recipes, or cooking; may cook elaborate dinners for others, but not eat the food themselves or consume a very small portion. * Admiration of thinner people. * Thoughts of being fat or not thin enough * An altered mental representation of one's body * Difficulty in abstract thinking and problem solving * Rigid and inflexible thinking * Poor self-esteem * Hypercriticism and clinical perfectionism Affective symptoms * Depression * Ashamed of oneself or one's body * Anxiety disorders * Rapid mood swings * Emotional dysregulation * Alexithymia Behavioral symptoms * Food restrictions despite being underweight or at a healthy weight. * Food rituals, such as cutting food into tiny pieces, refusing to eat around others, and hiding or discarding of food. * Purging (only in the<unk>  purging subtype) with laxatives, diet pills, ipecac syrup, or diuretics to flush food out of their system after eating or engage in self-induced vomiting. * Excessive exercise, including micro-exercising, for example making small persistent movements of fingers or toes. *Self harming or self-loathing. *Solitude: may avoid friends and family and become more withdrawn and secretive. Perceptual symptoms * Perception of self as overweight, in contradiction to an underweight reality (namely "body image disturbance" ) * Intolerance to cold and frequent complaints of being cold; body temperature may lower (hypothermia) in an effort to conserve energy due to malnutrition. * Altered body schema (i.e. an implicit representation of the body evoked by acting) * Altered interoception Interoception Interoception involves the conscious and unconscious sense of the internal state of the body, and it has an important role in homeostasis and regulation of emotions. Aside from noticeable physiological dysfunction, interoceptive deficits also prompt individuals with<unk>  to concentrate on distorted perceptions of multiple elements of their body image. This exists in both people with<unk>  and in healthy individuals due to impairment in interoceptive sensitivity and interoceptive awareness. Aside from weight gain and outer appearance, people with<unk>  also report abnormal bodily functions such as indistinct feelings of fullness. This provides an example of miscommunication between internal signals of the body and the brain. Due to impaired interoceptive sensitivity, powerful cues of fullness may be detected prematurely in highly sensitive individuals, which can result in decreased calorie consumption and generate anxiety surrounding food intake in<unk>  patients. People with<unk>  also report difficulty identifying and describing their emotional feelings and the inability to distinguish emotions from bodily sensations in general, called alexithymia. Interoceptive awareness and emotion are deeply intertwined, and could mutually impact each other in abnormalities.<unk>  patients also exhibit emotional regulation difficulties that ignite emotionally-cued eating behaviors, such as restricting food or excessive exercising. Impaired interoceptive sensitivity and interoceptive awareness can lead<unk>  patients to adapt distorted interpretations of weight gain that are cued by physical sensations related to digestion (e.g., fullness). Combined, these interoceptive and emotional elements could together trigger maladaptive and negatively reinforced behavioral responses that assist in the maintenance of<unk> . In addition to metacognition, people with<unk>  also have difficulty with social cognition including interpreting others’ emotions, and demonstrating empathy. Abnormal interoceptive awareness and interoceptive sensitivity shown through all of these examples have been observed so frequently in<unk>  that they have become key characteristics of the illness. Comorbidity Other psychological issues may factor into<unk> . Some people have a previous disorder which may increase their vulnerability to developing an eating disorder and some develop them afterwards. The presence of psychiatric comorbidity has been shown to affect the severity and type of<unk>  symptoms in both adolescents and adults. Obsessive-compulsive disorder (OCD) and obsessive-compulsive personality disorder (OCPD) are highly comorbid with AN. OCD is linked with more severe symptomatology and worse prognosis. The causality between personality disorders and eating disorders has yet to be fully established. Other comorbid conditions include depression, alcoholism, borderline and other personality disorders, anxiety disorders, attention deficit hyperactivity disorder, and body dysmorphic disorder (BDD). Depression and anxiety are the most common comorbidities, and depression is associated with a worse outcome. Autism spectrum disorders occur more commonly among people with eating disorders than in the general population. Zucker et al. (2007) proposed that conditions on the autism spectrum make up the cognitive endophenotype underlying<unk>  and appealed for increased interdisciplinary collaboration.
Anorexia nervosa
Substance use disorder
Bulimia nervosa
Orthorexia nervosa
Body dysmorphic disorder
Binge eating disorder
Inflammatory bowel disease
Night eating syndrome