Frequency
To be diagnosed as suffering from bulimia a person should have been displaying bingeing and purging on average at least 2 times a week for over 3 months.
Body image
Someone suffering from bulimia, like in anorexia, often has an inappropriate perception of their own body.
Different from anorexia
Because people with bulimia often purge after the bingeing they are often of normal weight. However, like people who suffer from anorexia, they may fear gaining weight, have a strong desire to lose weight and feel very dissatisfied with their bodies. People with bulimia will often perform the behaviors in secret, as they feel disgusted and ashamed when they binge.
Main differences between anorexia nervosa and bulimia nervosa
Anorexia
- Severely underweight
- Not hungry
- Purge to maintain low weight
- Less anti social behavior
- Amenorrhea
- Tends to be obsessional
- Greater self-control (over controlling)
- More immature and likely to reject the feminine role
- More likely to have been compliant towards family pre-disorder
Bulimia
- Slightly underweight or near normal weight
- Intense hunger
- Purge to compensate for over eating
- Tends to anti-social behavior and alcohol abuse
- amenorrhea only if weight loss is extreme
- tends to be dramatic
- more impulses and emotionally unstable
- more mature and likely to be sexually active
- more likely to have been in conflict with family pre-disorder
Many people who have eating disorders show the same behaviors
restricted calorie intake individuals often set themselves extremely unrealistic targets such as 300 calories.
Fear of eating many people develop an extremely unhealthy fear of eating, often people complain of nightmares related to food
Cessation of eating this provides comfort and gives a feeling of control, described as “those old comfy habits”
A sense of being out of control not eating makes the person feel like they’re in control
Excessive exercise some people with anorexia have been known to exercise for 8 hours a day.
Low self-esteem many feel like they’re not beautiful, and have the desire to look like a model. Many don’t take compliments very well. When someone says they look nice a person with anorexia wouldn’t believe them.
Hiding weight loss many will hide the fact that they’ve lost so much weight, by methods such as wearing baggy clothes and they get irritated when questioned about their eating.
The cause of these eating disorders is unclear however many studies have been done to try and determine the reason for their occurrence.
Some data has shown that eating disorders may be genetic, it could be down to a combination of nature and nurture. Holland et al. did a study to find out if this was so.
Aims
The aim of the study was to find out is anorexia has a genetic basis. It explores the possibility by comparing anorexia in identical twins, and non identical twins. As the twins will be raised in the same environment, similarity may be due to nature or nurture. However, if the identical twins are more similar, it implies that genes play a bigger role.
Procedures
45 pairs of female twins were interviewed, in which atleast one twin had anorexia. The intiviewers established the clinical characteristics observed, as well as the occurance of anerexis in any close relatives. They also noted the girls body mass and the length of amenorrhea, and they were asked about their drive to be thin.
There were 25 identical twins and 20 non identical twins used in the study.
Findings
There was found to be a significantly higher concordance in the identical twins, 56% of the identical twins were concordant, where as only 5% of the non identical twins were. There were also found to be a significant number of anorexias in the relatives compared to the normal population. The general population of anorexia is 0.1% where as in this study, first degree relatives were found to have 4.9% anerexias and the second degree relatives 1.2%. the measures of body mass and the drive to be thin were shown to be inheritable as there was a greater similarity between the identical twins.
Conclusions
This study suggests that anorexia has a large genetic link. The figure of inheritability may be as high as 80%. 80% of anorexia cases are due to genetic reasons and 20% are down to nurture. However, what is inherited may be a sensitivity to environmental factors.
Criticisms
A found difficulty in studies of anorexia is that the actual diagnosis of any individual is never certain. Some people may suffer from anorexia and bulimia, though sometimes not at the same time. This means that maybe its not anorexia that is genetic, but a weakness to eating disorders.
It may also be that identical twins get treated more similarly, and so their environment is more similar then the non identical twins, which could explain the higher concordance rates. It is also possible that twins may imitate each other which would be more likely in identical twins, although in some cases the twins were living in different countries and they concealed their eating disorder from the other twin.
Anorexia, until recently was only found in western society. However, it is now beginning to become more and more common all over the world.
Becker, did a study in Fiji. Until recently on the island weighing a lot was considered a desired characteristic. When television was first introduce to the island the people begun to be exposed to western shows, Becker wanted to see if this had an effect on the occurrence of eating disorders.
In 1995, when western TV was first introduced on the island 63 native Fijian girls were asked to fill out a questionnaire about their attitudes towards eating and their TV viewing habits. After 3 years another 65 girls were re questioned, to assess the impact TV had.
Girls who were reported to be vomiting to control their weight, and eating habits that may be indicating an eating disorder were both more common after the 3 years of TV exposure. Before the exposure only 3% were reported to be vomiting to loose weight, which went up to 15% after 3 years. Also before the exposure 13% were indicating possible eating disorders, which went up to 29%.
These findings indicated a strong link between the exposure to western TV and eating disorders. The new desire to be thin is a sign that the Fijian girls are beginning to conform to western cultural standards.
Even with these findings however, it cannot be assumed that watching western TV causes eating disorders. It was a natural study and so the IV was not manipulated. The change in attitude may have been because of the cultural strain to keep up with technologically more advanced culture.
Using these two studies, its shown that anorexia could be caused by biological reasons or psychological reasons. It might also be a combination of the two. Studies have also shown that it is similar in bulimia cases. There are also both biological and psychological reasons for its occurrence.
The biological causes for bulimia were looked into by Kendler et al.. They aimed to establish whether the increased incidence of bulimia in families was due to environmental or genetic reasons. This was done (as in the study into anorexia) by using identical and non identical twins.
In the study over 1,000 pairs of twins were contacted by using data from the Virginia twin registry. All of the twins were interviewed by trained interviewers. The same interviewer never interviewed both members of a twin pair.
In the identical twins it was found that there was a 26% concordance between twin pairs and in non identical twins it was only 16%. Out of the sample interviewed there were 123 cases of bulimia, most of these twins also reported some other sort of mental disorders at some point in their lives such as anorexia, depression and phobia.
The higher concordance in the identical twins indicates that there is a strong genetic component in bulimia. However, it’s lower then that in anorexia. It was suggested that just over half of the bulimia cases were due to genetic factors which is significantly lower then the 80% in anorexia cases. The often occurrence of other mental disorders suggests that it might not be bulimia that is inherited but a genetic weakness to mental disorders.
A more recent study has no concluded that 83% of cases are genetically influenced and that anorexia is only 58%. This both supports and contradicts Kendlers findings. Its supportive because there is now further evidence of genetic causes however, it contradicts because it suggests a greater genetic component in bulimia. One cause of this may be the issue of reliability in diagnosis.
There may also be a reason that twins may be more prone to mental disorders, therefore the findings would not be reliable. It’s possible that twins experience more stress and so are genetically more venerable.
The psychological causes for bulimia were researched by Cutts and Barrios. A lot have researchers have suggested that a fear of weight gain underlies both anorexia and bulimia but few have tested this belief. The fear of weight gain is an example of a distorted perception. This study investigated whether such fear is more prevalent in people with bulimia then in others.
30 females aged between 18 and 25were assigned to an individual with bulimia or a control group on the basis of questionnaires and interviews. Then they were all tested in a laboratory. They listened to two descriptions, one was of a neutral scene, (sitting in a library) and one was of weight gain (imagine they have gained 5 pounds) both situations were described to them by a man and they were asked in both cases to imagine themselves in the situations. Their responses were measured by recording facial muscle activity, heart rate and skin resistance. They were also asked to report their own reactions using a provided check list.
Both groups of participants showed very similar responses to the neutral scene, but different responses to the weight gain scene. The group with bulimia showed higher physiological activity when imagining the weight gain. They also reported greater subjective distress and their overt behavior was rated as being higher.
These findings supported the theory that fear of weight gain may be a factor in bulimia. Such faulty perceptions could trigger biological responses and a behavioral cycle of reinforcements. If someone fears weight gain, ho or she diets and starvation leads to changes in neurotransmitters. If an individual starts losing weight and dieting then this leads to an increased attention and attractiveness, encouraging further weight control.
The found concept of faulty cognitions may also offer a form of treatment for the disorder. By dealing with the fear of weight gain itself. It may also offer methods of detecting people at risk of developing bulimia.
It may also be that certain characteristics co-vary with a persons faulty perceptions. E.g. a person, who has maladaptive assumptions, may also have a more rigid cognitive style. It could therefore be this rigid cognitive style rather then the faulty perceptions that causes bulimia.
