Prevention aims to promote a healthy development before the occurrence of eating disorders. It also intends early identification of an eating disorder before it is too late to treat. Children as young as ages 5–7 are aware of the cultural messages regarding body image and dieting. Prevention comes in bringing these issues to the light. The following topics can be discussed with young children (as well as teens and young adults).

- Emotional Bites: a simple way to discuss emotional eating is to ask children about why they might eat besides being hungry. Talk about more effective ways to cope with emotions, emphasizing the value of sharing feelings with a trusted adult.

- Say No to Teasing: another concept is to emphasize that it is wrong to say hurtful things about other people's body sizes.

- Body Talk: emphasize the importance of listening to one's body. That is, eating when you are hungry (not starving) and stopping when you are satisfied (not stuffed). Children intuitively grasp these concepts.

- Fitness Comes in All Sizes: educate children about the genetics of body size and the normal changes occurring in the body. Discuss their fears and hopes about growing bigger. Focus on fitness and a balanced diet.

Internet and modern technologies provide new opportunities for prevention. On-line programs have the potential to increase the use of prevention programs. The development and practice of prevention programs via on-line sources make it possible to reach a wide range of people at minimal cost. Such an approach can also make prevention programs to be sustainable.

According to the National Eating Disorder Information Centre (NEDIC), the first step for someone going through anorexia athletica is to realize their eating and exercise habits are hurting them. Once an individual has realized they have a disorder, an appointment should be made with the family doctor. A family doctor can advise further medical attention if needed. With sports anorexia, it is important to go to a dietitian as well as a personal trainer. People with sports anorexia need to learn the balance between exercise and caloric intake.

There are two main types of treatment given to those suffering with bulimia nervosa; psychopharmacological and psychosocial treatments.

Social isolation has been shown to have a deleterious effect on an individual's physical and emotional well-being. Those that are socially isolated have a higher mortality rate in general as compared to individuals that have established social relationships. This effect on mortality is markedly increased in those with pre-existing medical or psychiatric conditions, and has been especially noted in cases of coronary heart disease. "The magnitude of risk associated with social isolation is comparable with that of cigarette smoking and other major biomedical and psychosocial risk factors." (Brummett "et al.")

Social isolation can be inherently stressful, depressing and anxiety-provoking. In an attempt to ameliorate these distressful feelings an individual may engage in emotional eating in which food serves as a source of comfort. The loneliness of social isolation and the inherent stressors thus associated have been implicated as triggering factors in binge eating as well.

Waller, Kennerley and Ohanian (2007) argued that both bingeing–vomiting and restriction are emotion suppression strategies, but they are just utilized at different times. For example, restriction is used to pre-empt any emotion activation, while bingeing–vomiting is used after an emotion has been activated.

Some of the differential or comorbid medical diagnoses may include:

- achalasia – There have been cases where achalasia, a disorder of the esophagus which affects peristalsis, has been misdiagnosed as AN. It has been reported in cases where there is sub-clinical manifestation of anorexia nervosa and also in cases where the full diagnostic criteria AN have been met.

- acute pandysautonomia is one form of an autonomic neuropathy, which is a collection of various syndromes and diseases which affect the autonomic neurons of the autonomic nervous system (ANS). Autonomic neuropathies may be the result of an inherited condition or they may be acquired due to various premorbid conditions such as diabetes and alcoholism, bacterial infection such as Lyme disease or a viral illness. Some of the symptoms of ANS which may be associated with an ED include nausea, dysphagia, constipation, pain in the salivary glands, early saiety. It also affects peristalsis in the stomach. Acute pandysautonomia may cause emotional instability and has been misdiagnosed as various psychiatric disorders including hysterical neurosis and anorexia nervosa.

- Lupus: various neuropsychiatric symptoms are associated with systemic lupus erythematosus (SLE), including depression. Anorexia and weight loss also may occur with SLE and while rare it may be misdiagnosed as AN.

- Lyme disease is known as the "great imitator", as it may present as a variety of psychiatric or neurologic disorders including anorexia nervosa. "A 12 year old boy with confirmed Lyme arthritis treated with oral antibiotics subsequently became depressed and anorectic. After being admitted to a psychiatric hospital with the diagnosis of anorexia nervosa, he was noted to have positive serologic tests for Borrelia burgdorferi. Treatment with a 14 day course of intravenous antibiotics led to a resolution of his depression and anorexia; this improvement was sustained on 3 year follow-up." Serologic testing can be helpful but should not be the sole basis for diagnosis. The Centers for Disease Control (CDC) issued a cautionary statement (MMWR 54;125) regarding the use of several commercial tests. Clinical diagnostic criteria have been issued by the CDC (CDC, MMWR 1997; 46: 531-535).

- Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare genetic disorder characterized by gastrointestinal dysmotility, severe cachexia progressive external ophthalmoplegia, post-prandial emesis (vomiting after eating), peripheral neuropathy, and diffuse leukoencephalopathy. Onset is prior to age 20 in 60% of cases. ""Miss A" was a 21-year-old Indian woman diagnosed as having treatment-resistant anorexia nervosa." It was subsequently proven to be MNGIE

- superior mesenteric artery syndrome (SMA syndrome) "is a gastrointestinal disorder characterized by the compression of the third or transverse portion of the duodenum against the aorta by the superior mesenteric artery resulting in chronic partial, incomplete, acute or intermittent duodenal obstruction". It may occur as a complication of AN or as a differential diagnosis. There have been reported cases of a tentative diagnosis of AN, where upon treatment for SMA syndrome the patient is asymptomatic.

- Addison's disease is a disorder of the adrenal cortex which results in decreased hormonal production. Addison's disease, even in subclinical form, may mimic many of the symptoms of anorexia nervosa.

- Brain tumors: There are multiple cases were the neuropsychiatric symptoms of a brain tumor were attributed to AN, resulting in misdiagnosis. The tumors in these cases were noted in various regions of the brain including the medulla oblongata, hypothalamus, pituitary gland, pineal gland and the obex.

- Simmond's disease (organic hypopituitarism) – "A 20-year-old Japanese man with a hypothalamic tumor which caused hypopituitarism and diabetes insipidus was mistakenly diagnosed as anorexia nervosa because of anorexia, weight loss, denial of being ill, changes in personality, and abnormal behavior resembling the clinical characteristics of anorexia nervosa"

- Brain calcification either dystrophic calcification or metastatic calcification can present with neuropsychiatric symptoms including those associated with AN and comorbid disorders such as obsessive compulsive disorder.

- cysts that occur in the central nervous system such as dermoid cysts and arachnoid cysts can cause neuropsychiatric symptoms including psychosis.

- Celiac disease is an inflammatory disorder triggered by peptides from wheat and similar grains which cause an immune reaction in the small intestine. "information on the role of the gastrointestinal system in causing or mimicking eating disorders is scarce."(Leffler DA "et al.")

- Gall bladder disease which may be caused by inflammation, infection, gallstones, obstruction of the gallbladder or torsion of the gall bladder – Many of the symptoms of gall bladder disease may mimic anorexia nervosa (AN). Laura Daly, a woman from Missouri, suffered from an inherited disorder in which the gall bladder was not properly attached; the resultant complications led to multiple erroneous diagnoses of AN. Upon performance of a CCK test, standard imaging techniques are done with the patient lying prone, in this instance it was done with the patient in an upright position. The gall bladder was shown to be in an abnormal position having flipped over the liver. The gallbladder was removed and the patient has since recovered. The treatment was performed by William P. Smedley in Pennsylvania.

- colonic tuberculosis misdiagnosed as anorexia nervosa in a physician at the hospital where she worked – "This patient, who had severe wasting, was misdiagnosed as having anorexia nervosa despite the presence of other symptoms suggestive of an organic disease, namely, fever and diarrhea"(Madani, A 2002).

- Crohn's disease: "We report three cases of young 18 to 25 year-old girls, initially treated for anorexia nervosa in a psychiatric department. Diagnosis of Crohn's disease was made within 5 to 13 years."(Blanchet C, Luton JP. 2002)"This disease should be diagnostically excluded before accepting anorexia nervosa as final diagnosis". (Wellmann W "et al.")

- hypothyroidism, hyperthyroidism, hypoparathyroidism and hyperparathyroidism may mimic some of the symptoms of, can occur concurrently with, be masked by or exacerbate an eating disorder and/or various comorbid disorders such as anxiety and depression.

- Insulinomas are (pancreatic tumors) that cause an overproduction of insulin, causing hypoglycemia. Various neurological deficits have been ascribed to this condition including misdiagnosis as an eating disorder.

- Multiple sclerosis (encephalomyelitis disseminata) is a progressive autoimmune disorder in which the protective covering (myelin sheath) of nerve cells is damaged as a result of inflammation and resultant attack by the bodies own immune system. In its initial presentation, MS has been misdiagnosed as an eating disorder.

Few studies guide the treatment of individuals with OSFED. However, cognitive behavioral therapy (CBT), which focuses on the interplay between thoughts, feelings, and behaviors, has been shown to be the leading evidence-based treatment for the eating disorders of BN and BED. For OSFED, a particular cognitive behavioral treatment can be used called CBT-Enhanced (CBT-E), which was designed to treat all forms of eating disorders. This method focuses not only what is thought to be the central cognitive disturbance in eating disorders (i.e., over-evaluation of eating, shape, and weight), but also on modifying the mechanisms that sustain eating disorder psychopathology, such as perfectionism, core low self-esteem, mood intolerance, and interpersonal difficulties. CBT-E showed effectiveness in two studies (total N = 219) and well maintained over 60-week follow-up periods. CBT-E is not specific to individual types of eating disorders but is based on the concept that common mechanisms are involved in the persistence of atypical eating disorders, AN, and BN.

Some researchers have also claimed positive outcomes in hypnotherapy.

With time the symptoms of ARFID can lessen and can eventually disappear without treatment. However, in some cases treatment will be needed as the symptoms persist into adulthood. The most common type of treatment for ARFID is some form of cognitive-behavioral therapy. Working with a clinician can help to change behaviors more quickly than symptoms may typically disappear without treatment. Also hypnotherapy may be used. In that it lessens the anxiety associated with food.

There are support groups for adults with ARFID.

Diet is the most essential factor to work on in people with anorexia nervosa, and must be tailored to each person's needs. Food variety is important when establishing meal plans as well as foods that are higher in energy density. People must consume adequate calories, starting slowly, and increasing at a measured pace. Evidence of a role for zinc supplementation during refeeding is unclear.

The rate of refeeding can be difficult to establish, because the fear of refeeding syndrome (RFS) can lead to underfeeding. It is thought that RFS, with falling phosphate and potassium levels, is more likely to occur when BMI is very low, and when medical comorbidities such as infection or cardiac failure, are present. In those circumstances, it is recommended to start refeeding slowly but to build up rapidly as long as RFS does not occur. Recommendations on energy requirements vary, from 5–10 kCal/Kg/day in the most medically compromised patients, who appear to have the highest risk of RFS to 1900 Kcal/day

Children can benefit from a four stage in-home treatment program based on the principles of systematic desensitization. The four stages of the treatment are record, reward, relax and review.

- In the record stage, children are encouraged to keep a log of their typical eating behaviors without attempting to change their habits as well as their cognitive feelings.

- The reward stage involves systematic desensitization. Children create a list of foods that they might like to try eating some day. These foods may not be drastically different from their normal diet, but perhaps a familiar food prepared in a different way. Because the goal is for the children to try new foods, children are rewarded when they sample new foods.

- The relaxation stage is most important for those children that suffer severe anxiety when presented with unfavorable foods. Children learn to relax to reduce the anxiety that they feel. Children work through a list of anxiety-producing stimuli and can create a story line with relaxing imagery and scenarios. Often these stories can also include the introduction of new foods with the help of a real person or fantasy person. Children then listen to this story before eating new foods as a way to imagine themselves participating in an expanded variety of foods while relaxed.

- The final stage, review, is important to keep track of the child's progress. It is important to include both one-on-one sessions with the child, as well as with the parent in order to get a clear picture of how the child is progressing and if the relaxation techniques are working.

Three other classes of medications are also used in the treatment of binge eating disorder: antidepressants, anticonvulsants, and anti-obesity medications. Antidepressant medications of the selective serotonin reuptake inhibitor (SSRI) class such as fluoxetine, fluvoxamine, or sertraline have been found to effectively reduce episodes of binge eating and reduce weight. Similarly, anticonvulsant medications such as topiramate and zonisamide may be able to effectively suppress appetite. The long-term effectiveness of medication for binge eating disorder is currently unknown.

Trials of antidepressants, anticonvulsants, and anti-obesity medications suggest that these medications are superior to placebo in reducing binge eating. Medications are not considered the treatment of choice because psychotherapeutic approaches, such as CBT, are more effective than medications for binge eating disorder. Medications also do not increase the effectiveness of psychotherapy, though some patients may benefit from anticonvulsant and anti-obesity medications, such as Phentermine/topiramate, for weight loss.

As of January 2015, lisdexamfetamine was the only drug approved by the Food and Drug Administration in the United States specifically for the treatment of binge eating.

Counselling and certain medication, such as lisdexamfetamine and selective serotonin reuptake inhibitor (SSRIs), may help. Some recommend a multidisciplinary approach in the treatment of the disorder.

Few studies to date have examined OSFED prevalence. The largest community study is by Stice (2013), who examined 496 adolescent females who completed annual diagnostic interviews over 8 years. Lifetime prevalence by age 20 for OSFED overall was 11.5%. 2.8% had atypical AN, 4.4% had subthreshold BN, 3.6% had subthreshold BED, and 3.4% had purging disorder. Peak age of onset for OSFED was 18–20 years. NES was not assessed in this study, but estimates from other studies suggest that it presents in 1% of the general population.

A few studies have compared the prevalence of EDNOS and OSFED and found that though the prevalence of atypical eating disorders decreased with the new classification system, the prevalence still remains high. For example, in a population of 215 young patients presenting for ED treatment, the diagnosis of EDNOS to OSFED decreased from 62.3% to 32.6%. In another study of 240 females in the U.S. with a lifetime history of an eating disorder, the prevalence changed from 67.9% EDNOS to 53.3% OSFED. Although the prevalence appears to reduce when using the categorizations of EDNOS vs. OSFED, a high proportion of cases still receive diagnoses of atypical eating disorders, which creates difficulties in communication, treatment planning, and basic research.

The differential diagnoses of anorexia nervosa (AN) includes various types of medical and psychological conditions, which may be misdiagnosed as AN. In some cases, these conditions may be comorbid with AN because the misdiagnosis of AN is not uncommon. For example, a case of achalasia was misdiagnosed as AN and the patient spent two months confined to a psychiatric hospital. A reason for the differential diagnoses that surround AN arise mainly because, like other disorders, it is primarily, albeit defensively and adaptive for, the individual concerned.

Anorexia Nervosa is a psychological disorder characterized by extremely reduced intake of food. People suffering from Aneroxia Nervosa have a low self-image and consider themselves overweight.

Common behaviors and signs of someone suffering from AN:

- Forcing oneself to vigorously exercise even in adverse conditions or when their health does not permit it.

- Forcing own self to urinate and excrete waste product from the body.

- Using substituted amphetamines (stimulants that can reduce appetite) to reduce appetite.

- Skin turning yellow

There is not one single cause of anorexia athletica, but many factors that are involved in the disorder. Research has shown that an area on chromosome 1 is linked to anorexia nervosa-sports anorexia. Thus, a person is more likely to have anorexia athletica if someone in their immediate family has had the disorder. Not only genetics, but also the environment a person is in, has a major impact on the disorder. Coaches and parents often suggest to their athlete/child to lose weight in order to perform better. Sports such as figure skating, ballet, and gymnastics promote both male and female athletes to have a thin figure. Females who partake in sports can suffer from a syndrome known as the triad. The media play a very significant role in pressuring athletes to have the ‘perfect’ body and to be thin, which can also trigger sports anorexia.

Emotional eating may qualify as avoidant coping and/or emotion-focused coping. As coping methods that fall under these broad categories focus on temporary reprieve rather than practical resolution of stressors, they can initiate a vicious cycle of maladaptive behavior reinforced by fleeting relief from stress. Additionally, in the presence of high insulin levels characteristic of the recovery phase of the stress-response, glucocorticoids trigger the creation of an enzyme that stores away the nutrients circulating in the bloodstream after an episode of emotional eating as visceral fat, or fat located in the abdominal area. Therefore, those who struggle with emotional eating are at greater risk for abdominal obesity, which is in turn linked to a greater risk for metabolic and cardiovascular disease.

There is no quick cure, and treatment will be based on what problems may be causing the feeding disorder. Depending on the condition, the following steps can be taken: increasing the number of foods that are accepted, increasing the amount of calories and the amount of fluids; checks for vitamin or mineral deficiencies; finding out what the illnesses or psychosocial problems are. To accomplish these goals patients may have to be hospitalized for extensive periods of time. Treatment involves professionals from multiple fields of study including, but not limited to; behavior analysts (Behavioral interventions), occupational and speech therapist who specialize in feeding disorders, dietitians, psychologists and physician. To obtain the best results, treatment should include a behavior modification plan under the guidance of multiple professionals. If the child has oral motor difficulties related to the feeding disorder a pediatric occupational or speech therapist who is trained in feeding disorders and oral motor function should help develop a plan.

There are numerous ways in which individuals can reduce emotional distress without engaging in emotional eating. The most salient choice is to minimize maladaptive coping strategies and to maximize adaptive strategies. A study conducted by Corstorphine et al. in 2007 investigated the relationship between distress tolerance and disordered eating. These researchers specifically focused on how different coping strategies impact distress tolerance and disordered eating. They found that individuals who engage in disordered eating often employ emotional avoidance strategies. If an individual is faced with strong negative emotions, they may choose to avoid the situation by distracting themselves through overeating. Discouraging emotional avoidance is thus an important facet to emotional eating treatment. The most obvious way to limit emotional avoidance is to confront the issue through techniques like problem solving. Corstorphine et al. showed that individuals who engaged in problem solving strategies enhance one's ability to tolerate emotional distress. Since emotional distress is correlated to emotional eating, the ability to better manage one's negative affect should allow an individual to cope with a situation without resorting to overeating.

One way to combat emotional eating is to employ mindfulness techniques. For example, approaching cravings with a nonjudgmental inquisitiveness can help differentiate between hunger and emotionally-driven cravings. An individual may ask his or herself if the craving developed rapidly, as emotional eating tends to be triggered spontaneously. An individual may also take the time to note his or her bodily sensations, such as hunger pangs, and coinciding emotions, like guilt or shame, in order to make conscious decisions to avoid emotional eating.

Emotional eating disorder predisposes individuals to more serious eating disorders and physiological complications. Therefore, combatting disordered eating before such progression takes place has become the focus of many clinical psychologists.

Some 25% to 40% of young children are reported to have feeding problems—mainly colic, vomiting, slow feeding, and refusal to eat. It has been reported that up to 80% of infants with developmental handicaps also demonstrate feeding problems while 1 to 2% of infants aged less than one year show severe food refusal and poor growth. Among infants born prematurely, 40% to 70% experience some form of feeding problem.

Purging disorder is an eating disorder characterized by recurrent purging (self-induced vomiting, misuse of laxatives, diuretics, or enemas) to control weight or shape in the absence of binge eating episodes.

Purging disorder differs from bulimia nervosa (BN) because individuals with purging disorder do not consume a large amount of food before they purge. In current diagnostic systems, purging disorder is a form of Other specified feeding or eating disorder (OSFED). Research indicates that purging disorder may be as common as bulimia nervosa or anorexia nervosa in women, that the syndrome is associated with clinically significant levels of distress, and that it appears to be distinct from bulimia nervosa on measures of hunger and ability to control food intake. Some of the signs of purging disorder are frequent trips to the bathroom directly after a meal, frequent use of laxatives, and obsession over one's appearance and weight. Other signs include swollen cheeks, popped blood vessels in the eyes, and clear teeth which are all signs of excessive vomiting.

Muscle dysmorphia's classification has been widely debated, and alternative "DSM" classifications have been proposed.

- Eating disorder: Many of muscle dysmorphia's traits overlap with those of eating disorders, including focus on body weight, shape, and modification, whereas body dysmorphic disorder otherwise usually lacks such dietary and exercise components. Also, persons experiencing muscle dysmorphia tend to score high on the Eating Attitudes Test and Eating Disorder Inventory, while muscle dysmorphia and anorexia nervosa share diagnostic crossover. Meanwhile, both muscle dysmorphia and eating disorders associate with higher impairment than does body dysmorphic disorder otherwise. And treatment for eating disorders may be effective for muscle dysmorphia.

- Behavioral addiction: Some researchers seek muscle dysmorphia's reclassification as a behavioral addiction. Muscle dysmorphia's obsession to maintain body image is enacted through particular activities, such as exercise, diet, and related shopping, which activities, as in behavioral addiction, are highly valued, modify mood, and may cause interpersonal conflicts. Also, tolerance to muscle building and dietary restriction can drive escalation of these activities to restore physiological or psychological effects. Further, abstinence from these activities can provoke withdrawal symptoms, and relapse into excessive engagement is apt to occur.

There are no specific guidelines for the treatment of diabetes and disordered eating, but the standard approach for treatment of two complex conditions as multidisciplinary team of professionals which in this case could include an endocrinologist, psychiatrist, psychologist, dietician, etc.

Eating disorder not otherwise specified (EDNOS) is an eating disorder that does not meet the criteria for: anorexia nervosa, bulimia nervosa, or binge eating. Individuals with EDNOS usually fall into one of three groups: sub-threshold symptoms of anorexia or bulimia, mixed features of both disorders, or extremely atypical eating behaviors that are not characterized by either of the other established disorders.

People with EDNOS have similar symptoms and behaviors to those with anorexia and bulimia, and can face the same dangerous risks.

EDNOS is the most prevalent eating disorder; about 60% of adults treated for eating disorders are diagnosed with EDNOS. EDNOS occurs in both sexes.

Treatment of muscle dysmorphia can be stymied by a patient's unawareness that the preoccupation is disordered or by avoidance of treatment. Scientific research on treatment of muscle dysmorphia is limited, the evidence largely in case reports and anecdotes, and no specific protocols have been validated. Still, evidence supports the efficacy of family-based therapy, cognitive behavioural therapy, and pharmacotherapy with selective serotonin reuptake inhibitors. Also limited is research on prognosis of the untreated.