Biology 202
2003 Second Web Paper
On Serendip

As medicine has progressed through the years, so have the avenues for diagnosing the various causes of many disorders. Recently there have been new discoveries about the disorder anorexia nervosa. Anorexia nervosa is a life-threatening eating disorder defined by a refusal to maintain body weight within 15 percent of an individual's minimal normal weight. (2) Other essential features of this disorder include an intense fear of gaining weight, a distorted body image, and amenorrhea (absence of at least three consecutive menstrual cycles when otherwise expected to occur) in women. (1) Theories about the causes of anorexia nervosa include the psychological, biological, and environmental. This paper will discuss the question of the multiple origins of anorexia nervosa, and attempt to identify a common underlying cause.

Conservative estimates suggest that one-half to one percent of females in the U.S. develop anorexia. Because more than 90 percent of all those who are affected are adolescent and young women, the disorder can be characterized primarily as a women's illness. It should be noted, however, that children as young as 7 have been diagnosed, and women 50, 60, 70, and even 80 fit the diagnosis. (5) Like all eating disorders, it tends to occur in pre or post puberty, but can develop at any life change. One reason younger women are particularly vulnerable to eating disorders is their tendency to go on strict diets to achieve an "ideal" figure. This obsessive dieting behavior reflects a great deal of today's societal pressure to be thin, which is seen in advertising and the media. Others especially at risk for eating disorders include athletes, actors, and models for whom thinness has become a professional requirement. (3)

The classic anorexic patient (although more and more variations are being seen) is an adolescent girl who is bright, does well in school, and is not objectively fat. She may be a few pounds overweight and begins to diet. She comes to relish the feeling of control that dieting gives her and refuses to stop. However grotesquely thin she may appear to others, she sees herself as fat. To combat the slowing of metabolism that accompanies starvation, severely restrictive eating is combined with excessive, frenetic physical activity. (7) The term anorexia, or absence of appetite, is a misnomer because patients are often hungry and can be quite preoccupied with food. They may cook elaborate meals for others, hoard food, or establish intricate rituals around the food they do eat. These behaviors resemble those seen in some patients with obsessive-compulsive disorders, and may extend outside the arena of eating. Generally, patients with anorexia nervosa are very secretive and defensive about their eating habits and may deny any problems when confronted. They may dress in oversized clothes (in an effort to hide their wasted bodies) or refuse to have meals with others. (3) The hallmark of anorexia nervosa is denial and preoccupation with food and weight. In fact, all eating disorders share this trait including binge eating disorder and compulsive eating. One of the most frightening aspects of the disorder is that people with anorexia continue to think they look fat, even when they are bone-thin. Their nails and hair become brittle, and their skin may become dry and yellow. Depression is common in patients suffering from this disorder. People with anorexia often complain of feeling cold (hypothermia) because their body temperature drops. They may develop long, fine hair on their body as a way of trying to conserve heat. Food and weight become obsessions as people with this illness constantly think about their next encounter with food. (6)

As previously stated the causation of anorexia nervosa can be biological, psychological, or environmental. One psychological theory is that food intake and weight are areas that a young woman can control in a life otherwise dictated by an overly involved family, which may include a parent who is unduly concerned with weight or appearance. (8) From this stems the idea that one cause of anorexia may be the development of control issues. Many anorexics admit that they began the downward spiral towards anorexia when they started to perceive that they had lost control of their lives. This is especially common in college students who perceive that they have no control over the direction of their lives. For example, the case of Betsy, who is a hard working college student in her second year. She is anxious about her future. Like her mother, Betsy gets depressed. She goes through periods when she feels very discouraged about life in general. She also is uncertain about how she looks though her friends think she looks great. (5) In an interview conducted with her psychologist, she stated " I began to stop eating as a way to gain some control over my life. I was shocked at the measure of relief that it gave me to have control of this tiny thing. From then on controlling what I ate became an obsession, a very twisted obsession." (5) It seems then, that one psychological causes of anorexia is a perceived lack of control in ones life. Through controlling ones food intake, anorexics are reaffirming that they have control. Can all of the psychological causes of anorexia nervosa be traced to a control issue?

Since the symptoms of anorexia often appear around puberty, another hypothesis is that the girl is afraid of becoming a woman, and therefore diets away all signs of puberty (i.e., breasts, hips, menses). The full-time preoccupation with weight also allows her to avoid adolescent social and sexual concerns and potential conflicts with parents. (8) In case of the pubescent girl, it is possible to trace the cause of anorexia past the initial preoccupation with weight to deeper control issues. The pubescent girl in the throw of fluctuating hormones, and massive physical change, would fit the bill of a person whom would feel as if they had lost control of their world. Their body is turning against them, what better way to reassert control than to regulate its intake of food and thus its shape. Puberty is also the time in which a girl begins to identify herself as a woman, both mentally and physically. She will look at her environment for female role models to copy. This leads to another cause of anorexia—the media. The role of the American cultural ideal of thinness is thought to contribute, at least by encouraging initial dieting, but the scope of its influence is unclear. On any given day, 25% of American men and 45% of American women are actively dieting; moreover, children are starting to diet as early as first grade. Anorexia is now being seen in nonwestern countries that receive American television, so it may be that a cultural ideal of thinness is a potent catalyst. (5)

We have seen that there are various psychological instigators for anorexia, most of which can be traced back to issues of control. However, many researchers propose that anorexia can also find some origin in a biological cause. Most advocates of the biological cause believe that anorexia is caused genealogically (i.e. passed down through their parents). (7) According to a recent study, mothers and sisters of people with anorexia or bulimia are at higher risk of having one of these disorders. Compared to the rest of the population, these mothers and sisters have a risk for anorexia that is 11 times higher and a risk for bulimia that is 4 times higher. (4) At this point one might ask, is it the similar genes or environment that is causing anorexia? As in most human disease, the answer appears to be "both." Better understanding of the genetic roots of eating disorders will make it easier to identify and understand the environmental factors. Some studies that were done on twins demonstrated that anywhere from 50 to 90% of the risk for anorexia is said to be genetic. (4) To date, medical science has not found a specific gene or genes that contribute to anorexia and bulimia. But this doesn't mean medical science has no clues. Genes that affect appetite may be involved. These genes would regulate the feeling of "fullness" after eating. People with anorexia may feel full early, and so suppress their appetites completely. (7)

There is also the issue of a common environment that might explain the higher rates of anorexia nervosa amongst mothers and sisters. Family dynamics must come strongly into play. The boundaries between generations tend to be blurred in the families of persons with eating disorders. That is, parents and children are constantly involved in each other's problems. Other researchers point to early events in family life that cause a "paralyzing sense of ineffectiveness." (5) In both events, perceived lack of control in ones life (due to overbearing parents, or a sense of ineffectiveness) can be associated with the initial issues. A this point the question is posed, since there is a link between family members and anorexia, why do only certain members of the family have anorexia and not the entire family? The genetic and environmental differences that explain differences in our appearance and health. Some family members will inherit genes that predispose to eating disorders, and others will not. Some family members will be exposed to environmental agents that trigger disease, and others will not. (5)

In this paper the question has been raised, what is the cause of anorexia nervosa? This question led to the idea that part of the cause of anorexia nervosa could be a perceived lack of control. To prove this we looked at the three main ideas's behind the causation of anorexia. Most physicians believe that anorexia can trace its origins to psychological, genetic, or environmental issues. In both the psychological and environmental cases it was demonstrated that, upon closer look, there was evidence that suggested a deeper problem of perceived loss of control. For example, the pubescent girl who finds herself going through many changes and becomes anorexic. At first glance the anorexia was caused by a fear of becoming a woman. Is this fear of becoming a woman not indicative of a greater fear of loss of control, not only of ones body (that is changing daily), but also of ones mind (that is at the beck and call of hormones)? In this case it is easy to link the cause of anorexia back to a control issue. Through the same method can we trace control issues back to the original cause of environment. The family environment was used as an explanation as to why mothers and sisters were more highly susceptible to anorexia. However, that same theory then suggested that early events in communal family life (i.e. death of a parent) could cause a "paralyzing sense of ineffectiveness," that in turn caused anorexia. This point easily flows over to prove that perceived lack of control was once again culpable as part of the cause of anorexia. Many conditions spanning from genetic to psychological all help cause anorexia, in most cases the common thread of control issues can be found in each. Future breakthroughs might identify even more causes of anorexia, and hopefully answer the genetic question. Yet no matter how much we research there will always be a part of the human mind that will remain a mystery.

World Wide Web Resources
1)Anorexia Nervosa, a site that give a thorough explanation of what anorexia nervosa is, and its symptoms.
2)Medical Student Conducted Studies, an interesting site that give a listing of studies that medical students are conducting. It also lists the results of the study. In this paper it helped to clearly outline the effects of anorexia/
3)Causes of Anorexia, this site lists the different causes for anorexia, and their effects on the body.
4)Entrez-PubMed, a wonderful site that lists the medical studies that were conducted by the government.
5)Hospital Practice , a site that lists the articles written by various different doctors. This is an extremely informative site that helped identify the broadly different causes of anorexia nervosa.
6)Link Between Depression and other Mental Illness, an article that discusses the links between mental illness and depression. It addresses a very wide variety of issues.
7)Genetics and Eating Disorders, this site looks at the link between genetics and eating disorders. It also looks at the different medical studies that have been conducted on the topic.
8)On the Teen Scene, this site looks at the effect of anorexia nervosa on teenagers. It looks at questions as to why it affect that one age group so hard, and its ramifications.


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