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Anorexia nervosa (commonly shortened to anorexia) is an eating disorder characterised by voluntary starvation and exercise stress. Anorexia nervosa is a complex disease, involving psychological, sociological and physiological components. A person who is suffering from anorexia is known as an 'anorexic,' 'anorectic,' or the less common 'anoretic.'
Anorectic and anoretic also refer to appetite-suppressing drugs.
Anorexia also refers to loss of appetite, usually considered as a medical symptom.
The causes of anorexia are a matter of debate in medical circles and society in general. General perspectives fit between the poles of it being physiological or psychological (with the potential for sociological and cultural influences being a cause to various degrees) in origin. Many now take the opinion that it is a mix of both, in that it is a psychological condition which is often (though not inherently) borne of certain conducive neurophysiologic conditions.
The primary physiological characteristics of anorexia nervosa are voluntary starvation and exercise stress. In addition to intentional starvation, subjects will also take part in a high level of physical activity. Anorexia nervosa also negatively impacts the immune system and the central nervous system (CNS).
Anorectic subjects will often go through a cycle of recovery and relapse.
There is increasing speculation that the onset of anorexia has a genetic component, with a certain gene linked to abnormalities with the neurotransmitter chemical serotonin being shown to be more common amongst sufferers than the general population. Such genetic characteristics might potentially equate to an easier path towards overly high serotonin levels, thus instilling heightened levels of anxiety and the like. Biologically, when a person is in a state of starvation, their levels of serotonin decrease, and thence increase again upon the consumption of food because of the tryptophan amino acids contained therein (typtophan is used by the body to synthesise serotonin). This raises the spectre that the anorectic is conditioned into avoiding food to reduce their anxiety, and that there may be yet another layer of complexity with respects to the cause/effect relationship between physiological factors and the mental beliefs of the anorectic.
Dietary minerals and heavy metals
Victims of mercury, lead, beryllium and arsenic poisoning have been known to develop anorexia as a symptom thereof. Some psychological traits associated with anorexia are consistent with deficiencies in important vitamins and minerals, such as magnesium and the B vitamins. Zinc deficiency is common among anorectics, thereby resulting in heightened levels of copper which is associated with depression and nervousness. That these deficiencies (or untoward exposure to heavy metals) can produce powerful psychological effects, such as depression, anxiety, and loss of appetite, is not widely known. Conversely, overexposure is also harmful.
There exists an animal model of anorexia nervosa that closely mimics the physiological effects of the disease. In the animal model, subjects are intentionally subject to starvation and access to unlimited ability to exercise. Under these conditions, without intervention, subjects will eventually run and starve themselves to death. Compared to cases of food restriction without exercise access, the subject will not starve themselves to death.
In the animal model of anorexia nervosa, it has been shown that repeated cycling of recover and relapse will lead to physiological adjustments from the subject. Subjects under these conditions will eventually become "resistant" to the animal model, and will not starve themselves to death. Subjects under these conditions show a metabolic adjustment.
Primary physiological effects
- Voluntary starvation
- Exercise stress
- Obsessive-compulsive behavior
In the animal model:
- Negative impact on the immune system
- Negative impact on the Central Nervous System
- Serotonin deficiency
Anorexia alters an individual's body image to the point where they may see themselves as being fat and bilious irrespective of their actual size. This distorted body image is a source of considerable anxiety, and losing weight is considered to be the solution. However, when a weight-loss goal is attained, the anorectic still feels overweight and in need of further weight-loss.
The attainment of a lower weight is typically viewed as a victory, and the gaining of weight as a defeat. "Control" is a factor strongly associated with anorexia, and an anorectic typically feels highly out of control in their life. However, the nature of the condition with respect to such psychological factors is highly complicated.
It is often the case that other psychological difficulties and mental illnesses exist alongside anorexia in the sufferer. Mild to severe manifestations of depression are common, partly because an inadequate food energy-intake is a well-known trigger for depression in susceptible individuals. Other afflictions may include self-harm and obsessive-compulsive disordered thinking (aside from such disordered thinking connected to their eating disorder). However, not all anorectics have any such problems besides their eating disorder.
Many anorectics reach a low level of bodyweight where hospitalisation and forced-feeding are required on a long-term or recurring basis in an attempt to keep them from literally starving themselves to death. Prolonged starvation will result in death as the body's systems shut down, this in itself being the major danger-factor of anorexia aside from mental suffering and the risk of suicide.
Some anorectics may incorporate bulimic behaviours into their illness: binge-eating and purging themselves of food on a regular or infrequent basis at certain times during the course of their disease. Alternatively, some individuals might switch from having anorexia to having bulimia. While bulimia poses less of a mortal danger to life and limb, many who have suffered both say that bulimia involves more mental suffering.
Anorexia alters one's body image so that one does not see the truth about oneself even when one looks in the mirror - to the anorectic mindset, there is no such thing as being too thin. Anorectics acknowledge their condition to different degrees - at one extreme, they do not see their "disease" as dangerous and resent being labelled as psychologically ill; at the other, they understand and accept that they have a problem, yet the anorexia still takes control over their thinking to fluctuating degrees. In ways not too dissimilar from people who have had cult programming or post-traumatic stress disorder, an anorectic may be "triggered" into manic disordered thinking by being exposed to certain words or conditions.
Some people eat unusually small amounts of food for reasons other than their own perceived obesity. Examples include those who fast for religious reasons, execute a hunger strike as a political statement, or are attempting to lengthen their lifespan through caloric restriction. Such individuals are not ordinarily considered anorectic, although some modern critics of religious asceticism have likened habitual fasting to anorexia.
The mass media and advertorial marketing, such as beauty advertising, are also frequently viewed as being implicated in triggering eating disorders in teenage girls, although it has recently come to light that there appear to be girls exhibiting anorectic behaviours in remote parts of Africa that have not been exposed to modern forms of advertising. These girls link their self-starvation to religious causes.
Although anorexia is usually associated with western cultures, the exposure to western media has caused the disease to appear in some third-world nations.
In recent years, the Internet has enabled anoretics and bulimics to contact and communicate with each other outside of a treatment environment, with much lower risks of rejection by mainstream society. If an anoretic is already socially withdrawn, such a network of friends can be very helpful in bringing them back. On the other hand, the Internet is also a powerful tool for people to isolate themselves. A variety of websites exist, some run by sufferers, some former sufferers, and some by professionals; attitudes on these sites range through a no-holds-barred, tough-love "put it in your mouth" approach through simple acceptance and even to promotion of anorexia as an "alternate lifestyle" (see pro-ana).
The following is considered the "textbook" definition of anorexia nervosa to assist doctors in making a clinical diagnosis . It is in no way representative of what a sufferer feels or experiences in living with the illness. It is important to note that an individual can still suffer from anorexia even if one of the below signs is not present. In other words, it is dangerous to read the diagnostic criteria and think either oneself or others must not be anorectic because one or more of the symptoms listed are not present.
- Refusal to maintain body weight at or above a minimally normal weight for age and height (e.g., weight loss leading to maintenance of body weight less than 85% of that expected; or failure to make expected weight gain during period of growth, leading to body weight less than 85% of that expected).
- Maintaining excessive physical activity.
- Intense fear of gaining weight or becoming fat, even though underweight.
- Disturbance in the way in which one's body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or denial of the seriousness of the current low body weight.
- In postmenarcheal females (women who have not yet gone through menopause), amenorrhea (the absence of at least three consecutive menstrual cycles).
Restricting Type: during the current episode of anorexia nervosa, the person has not regularly engaged in binge-eating or purging behavior (i.e., self-induced vomiting or the misuse of laxatives, diuretics, or enemas)
Binge-Eating Type or Purging Type: during the current episode of anorexia nervosa, the person has regularly engaged in binge-eating OR purging behavior (i.e., self-induced vomiting or the misuse of laxatives, diuretics, or enemas).
Anorexia has the highest death rate of any psychiatric illness. Starvation can cause major organs to shut down. A heart attack is one of the most common causes of death in those suffering with an eating disorder. People can die from eating disorders at any body-weight.
Osteoporosis is another danger of anorexia. Low calcium intake is only part of the problem. Even in those who take in adequate calcium through food or supplements, amenorrhea prevents the body from absorbing it fully.
While anorexia may occur in individuals across the demographic divides, it definitely appears to be far more prone to developing among those in certain groups, such as:
- females (95% of anorexia nervosa sufferers are females);
- those of age 10 through 25;
- people who are active in dancing, modeling or gymnastics;
- people of European racial descent;
- students who are under heavy workloads;
- those who have suffered traumatic events in their lifetime such as child abuse and sexual abuse ¹;
- those positioned in the higher echelons of the socioeconomic scale;
- the highly intelligent and/or high-achievers ;
Anorexia is typically stereotyped as being a disease of teenage females. However, in real-life, almost any individual can be a sufferer, as even children as young as three have been known to develop the disease. The most common times of onset are at puberty, and during times of transition such as moving from school to university. Males are at a greater risk of not recovering from the disease due to a reluctance to report symptoms.
Twenty years ago it was thought that for every 10-15 women with anorexia or bulimia, there was one man. Today researchers find that for every four females with anorexia, there is one male, and for every 8-11 females with bulimia, there is one male.
Though many do not realize it, younger children can also exhibit symptoms of anorexia. Children as young as five years may begin to diet, perhaps mimicking behaviour they see in their parents. These young anorectics have a fear of becoming "fat" and refuse to eat, as in classic anorexia.
Anorectic people may:
- be too thin and/or appear to have lost weight;
- be secretive about their eating and try to not eat whilst being around others;
- eat in a ritualistic nature (This can encompass taking abnormally small bites, cutting food up into abnormally small pieces, being sullen during mealtimes, staring at their food whilst eating, holding cutlery in odd ways or at strange angles at times, or eating slowly, especially when putting food into the mouth.);
- look longingly at or pay abnormal attention towards food but not eat it;
- cook wonderful meals for others but avoid eating the food they've made themselves;
- say they're too fat when they are not;
- have dry skin and thinning hair;
- suffer from poor health and sunken eyes;
- have grown lanugo, a thin hair that grows all over their body as a natural physiological reaction to severe starvation that serves to keep the body warm in the absence of fat;
- possess an extensive knowledge about the food energy contents of the different types of food, and the energy-burning effects of each form of exercise;
- faint or otherwise pass out (an effect of starvation);
- have amenorrhea, the absence of menstruation.
A person can be anorectic without displaying all of the above signs.
Although anorectics are less likely to choose fattening foods to eat, this is not always so. They may set their food-restriction objectives by food energy rather than by food type—for example, one may set a goal of 100 calories in a day and the food chosen to attain that number may very well be a cereal bar one day and an apple the next.
Successful treatment of, and recovery from, anorexia is possible, but it can take many years. The earlier intervention arrests the course of the disease, the more successful the treatment is likely to be. Anorexia nervosa has the highest death-rate of all mental illnesses, with as many as 20% of anorectics eventually dying of complications of the disease, usually from heart/organ failure or low levels of potassium. Once an anorectic reaches a certain weight, death becomes a very real possibility. The BMI (or body mass index) where this starts becoming a danger is generally around 12 to 12.5.(As a point of reference, a normal BMI is between 20 and 23, most "centrefold" models have a BMI of 18, and most fashion models come in at 17. An anorectic BMI is usually defined as being below 17.5.) Approaches include hospitalization, psychotherapy, specialised anorexia treatment-centres, and family counselling. The prescription of psychotropic drugs such as antidepressants is also practiced. Support groups such as Overeaters Anonymous, which deals with eating disorders in general, can also be helpful.
Appropriate treatment of any present vitamin and dietary-mineral deficiencies, particularly in the common case of zinc deficiency, may be highly beneficial to the sufferer's mental and physical wellbeing.
Anorexia is notoriously hard to treat, with sufferers often either emphatically denying that they are ill or paradoxically, accepting that they have anorexia, but seeing nothing wrong with their "lifestyle choice". This latter view is evidenced by the growing number of "pro-ana" websites and discussion groups where self-identified "anorectics" come together to reinforce their beliefs and behaviours, creating a positive feedback loop.
Another difficulty in treating anorexia nervosa is the prevalence of relapse.
Interacting with sufferers
The best help an anorectic can receive is unconditional love and empathy. Anorexia is fundamentally less about food than an individual's psychological need to feel safe - in that they do not.
As is common among sufferers of some eating disorders, an anorectic may be very secretive about their disorder. Being confronted by another about it for the first time may result in feelings of panic and distress, so an informed and considerate caution is recommended. However it is important to remember that anorexia is a dangerous disorder that signifies chronic suffering in an individual - it is important not to delay in seeking help for the person whom you believe has anorexia or bulimia. Researching the condition and consulting your local eating-disorder support-network are good beginnings.
In handling an anorectic dependent, it is dangerous to "just force" them to eat without support. Eating for most anorectics is not as easy as "just eat" as with non eating-disordered people. While being firm is important, keep in mind that eating things which are not considered "safe" will most likely trigger fear and panic in the sufferer.
- Having been a survivor of such abuse is not altogether rare among anorexia-sufferers, and therefore the possibility should be taken into empathetic consideration.
- Bulimia nervosa
- Muscle dysmorphia (reverse anorexia nervosa)
- Orthorexia nervosa
- Carpenters, Karen
- Randomized controlled trial of a treatment for anorexia and bulimia nervosa. Karolinska Institutet (Sweden) treatment model focussing on teaching people how to eat again. Supposes that psychiatric conditions could be more symptomatic than causal. Showing remarkably positive results and seeking further replication.
- The Stockholm solution
- The Something Fishy Website on Eating Disorders
- International Eating Disorder Referral and Information Center - EDReferral.com
- Wasted (ISBN 0-06-018739-5), by Marya Hornbacher, an autobiographical look at her lifetime of Bulimia nervosa and Anorexia nervosa.
- Dangers of anorexia nervosa
- Eating Disorder Center of CA
- The International Eating Disorders Centre
- Web4health Anorexia nervosa section
- Eating Disorders Association (EDA)
- BBC-Mental Health
- American Psychiatric Association
- Mental Health Matters: Anorexia
- Psych Forums: Anorexia Forum
- Healthy Within
- Anorexia Blogs
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