The only factor separating someone from an eating disorder may be a healthy dollop of self-delusion.

Psychologists have tried to identify whether individuals with eating problems have distorted perceptions or feelings about their bodies, but the findings have been unconvincing. Researchers from the University of Maastricht in the Netherlands recently tried a different approach. First they asked individuals from two groups to rate their own attractiveness. One group had symptoms of eating disorders. People in the other, control group had been chosen because their (normal) body sizes were similar to those of the disordered group. The investigators presented pictures of everyone’s bodies, with the heads cropped out, to two panels of evaluators. Somehow, despite the size similarity, both sets of evaluators rated those with eating disorders as less attractive — in accord with the ratings the disordered individuals gave themselves.

In contrast, the control subjects overestimated their own attractiveness, suggesting they have a biased, protective body image. To treat people with eating disorders, doctors might teach them to focus on their attractive features, the experimenters propose.