New Software Used to Test Body Shape Preferences

A distorted perception of body size and shape is a key factor in both anorexia nervosa and bulimia nervosa, but this is often hard to define. Previous attempts to do so have used methods like distorting a video image by stretching or compressing a figure on the X or Y axis.

Dr. M. J. Toe and colleagues at Newcastle University, in Newcastle Upon Tyne, UK, have developed computer software that they feel more realistically reflects the way fat is added or lost from the body (Br J Psychology 2003; 94:501). Unlike many body image software programs, which allow images to be stretched or compressed, the British software system uses biometric data based on real body shapes. According to the authors, this method also allows individual body parts to be altered separately, and thus it’s possible to determine if the patient is overestimating or underestimating a particular body part.

Another bonus, according to the authors, is that it is possible to calculate the apparent body mass index (BMI) of the modified pictures using the perimeter-area ratio—this allows comparison of the actual BMI with that calculated for the patient’s estimated and ideal bodies.

Putting the software to the test

When the software was tested on 30 anorexic patients, 30 bulimic patients, and 137 control observers, all three groups tended to overestimate their body size, but not significantly so. Both the control and bulimic observers preferred an “ideal body” with a BMI of 20, which is at the lower end of the “normal” BMI range. However, the anorexics chose an “ideal body” with a BMI of 15, which is on the borderline between emaciated and underweight BMI categories.