In today’s society, great importance is given to physical appearance. From the media to the most private forms of interaction, few areas of life allow us to move away from the general concept that equates thinness and physical attractiveness with perfection and success.
Anorexia and bulimia are two eating disorders in whose development social pressure to achieve an ideal physique plays a fundamental role. The proximity between these two diagnoses sometimes causes some confusion regarding their definition.
Defining Anorexia and Bulimia
Anorexia nervosa is characterized by the voluntary restriction of food intake and by progressive thinning to underweight. There is also a distortion of body image; this means that people with anorexia look thicker than they are.
Anorexia has two subtypes: restrictive, in which weight is lost mainly through fasting and physical exercise, and compulsive/purgative, in which binge eating and purging occur.
In bulimia emotional distress or stress triggers binge eating , usually of foods with a high caloric content, followed by purgative (vomiting, use of laxatives) or compensatory (fasting, intense exercise) behaviours that are the consequence of feelings of guilt or shame. During the binges, a feeling of loss of control over intake is experienced.
Bulimia is also classified according to two types, one purgative and one non-purgative, which rather corresponds to compensatory behaviors such as fasting.
Other psychological problems with a similar profile are orthorexia nervosa, which is characterized by an obsession with eating only healthy food, body dysmorphic disorder, which consists of an excessive concern for some physical defect, and muscular vigorexia or dysmorphia, a subtype of the former.
5 differences between anorexia and bulimia
Even keeping in mind that diagnoses are only tools for guidance and that the symptoms of anorexia and bulimia may overlap, it is useful to review the main differences between these two disorders as they are understood in the Psychology textbooks.
1. The main symptoms: restriction or binge eating
Behavioral symptoms are one of the fundamental differences between bulimia and anorexia. In general, in anorexia there is a strict control over behavior while bulimia has a more compulsive and emotional component.
In the case of bulimia the presence of frequent binges is necessary for the diagnosis. While these episodes may also occur in anorexia, they are basic only in the compulsive/purgative subtype, and tend to be much less intense than in bulimia.
Purgative and compensatory behaviours can occur in both disorders. However, in the case of bulimia one or both will always occur, as the person feels the need to lose the weight gained through the binges, whereas in anorexia these behaviors may be unnecessary if the caloric restriction is sufficient to meet the weight loss goals.
Binge eating disorder is another diagnostic entity that is exclusively characterized by recurrent episodes of uncontrolled eating. Unlike those in bulimia and anorexia, in this case the binges are not followed by purgative or compensatory behaviors.
2. Weight loss: underweight or fluctuating weight
The diagnosis of anorexia nervosa requires a persistent urge to lose weight and that it is significantly below the minimum weight it should be according to its biology. This is usually measured by the Body Mass Index or BMI, which is calculated by dividing the weight (in kilograms) by the height (in meters) squared.
In anorexia the BMI tends to be below 17.5, which is considered underweight, while the normal range is between 18.5 and 25. People with a BMI of more than 30 are considered obese.
In bulimia the weight is usually within the range considered healthy . However, there are significant fluctuations, so in periods when binge eating is predominant the person may gain a lot of weight, and when the restriction is maintained for a long time the opposite may occur.
3. The psychological profile: obsessive or impulsive
Anorexia tends to be related to control and order , while bulimia is more associated with impulsivity and emotionality.
Although these are only general tendencies, if we wanted to make a psychological profile of a “stereotypically anorexic” person we could qualify her as introverted, socially isolated, with low self-esteem, perfectionist and self-demanding. On the contrary, people with bulimia tend to be more emotionally unstable , depressive and impulsive, and more prone to addictions.
It is interesting to relate these diagnoses to the personality disorders that are most commonly associated with each of them. While in anorexia obsessive-compulsive and avoidant personalities predominate, in bulimia there are usually cases of histrionic and borderline disorder.
Additionally, in anorexia there is more frequent denial of the problem, which is more easily assumed in people with bulimia.
4. Physical consequences: serious or moderate
The physical alterations derived from anorexia are more severe than those caused by bulimia since the former can lead to death by starvation. In fact, in many cases of anorexia , hospitalization is used to bring the person back to an acceptable weight, while in bulimia this is significantly less frequent.
In anorexia, it is much more common for amenorrhea to occur, that is, the disappearance of menstruation or its non-appearance in cases that begin at a very early age. Dryness of the skin, capillary weakness and the appearance of lanugo (a very fine hair, like that of newborns), hypotension, sensation of cold, dehydration and even osteoporosis are also often detected. Most symptoms are attributable to starvation.
Some common physical consequences of bulimia are swelling of the parotid gland and the face, reduced potassium levels (hypokalemia), and tooth decay due to dissolution of the enamel caused by recurrent vomiting. Vomiting can also cause the so-called “Russell’s sign” , calluses on the hand due to rubbing the teeth.
These physical alterations depend more on each person’s specific behaviors than on the disorder itself. Thus, while vomiting may be more common in bulimia, an anorexic person who vomits repeatedly will also damage his or her tooth enamel.
5. The age of onset: adolescence or youth
Although these eating disorders can occur at any age, it is more common for each of them to begin at a certain period in life.
Bulimia typically starts in youth , between 18 and 25 years old. Since bulimia is related to psychosocial stress, its frequency of onset increases at about the same age when responsibilities and the need for independence become stronger.
On the other hand, anorexia tends to start at an earlier age , mainly in adolescence, between 14 and 18 years old. In general, the development of anorexia has been associated with the social pressures derived from sexual maturation and the adoption of gender roles, specifically female roles, since for men the demands of thinness are usually less.
“Bulimia” and “anorexia” are just labels
Although in this article we have tried to clarify what are the fundamental differences between the diagnosis of bulimia and that of anorexia, the truth is that both patterns of behavior are close in many ways. As we have seen, many of the behaviors characteristic of these two disorders, such as recurrent vomiting or intense exercise, are as much characteristic of one as the other, and in some cases only their frequency or centrality to the problem allows us to differentiate between anorexia and bulimia.
Furthermore, it is quite frequent that both diagnoses overlap , either successively or in alternation. For example, a case of anorexia in which binges occur from time to time could end up leading to bulimia. In addition, if the same person were to return to his or her previous patterns, this would again fit the diagnosis of anorexia. In general, if the conditions for a diagnosis of anorexia are met, the diagnosis of anorexia is given priority over bulimia.
This makes us reflect on the rigidity with which we generally conceptualize the disorders, whose names do not cease to be labels with the function of helping clinicians to have an overview of the most recommendable intervention tools when dealing with each of their cases.
- American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC: Author.
- Fernández- Aranda, F. and Turón, V. (1998). Eating disorders: Basic guide to treatment in anorexia and bulimia. Barcelona: Masson.