A new study provides evidence that anorexia in girls could be similar to autism in boys.

Lead by autism expert Simon Baron-Cohen, a professor of developmental psychopathology at the University of Cambridge, the study expanded on previous research that shows the compulsive behavior seen in people with autism is very similar to behaviors seen in anorexics.

Baron-Cohen and his team tested 66 girls ages 12 to 18 with anorexia and 1,609 girls without anorexia. Each was tested using the Autism Spectrum Quotient, the Empathy Quotient, and the Systemizing Quotient, three tests used to determine whether someone has autism.

Researchers found that girls with anorexia scored higher on the Spectrum and Systemizing Quotient tests, and slightly lower on the Empathy Quotient test, indicating that they have some distinctly autistic traits.

“Traditionally, anorexia has been viewed purely as an eating disorder. This is quite reasonable, since the girl’s dangerously low weight and their risk of malnutrition or even death has to be the highest priority,” Baron-Cohen said in a press release. “But this new research is suggesting that, underlying the surface behavior, the mind of a person with anorexia may share a lot with the mind of a person with autism.”

'Exclusive Focus on Oneself'

Anorexia nervosa is characterized by a refusal to maintain a minimum body weight and a preoccupation with food and weight loss. It typically affects girls and women, starts at a young age, and is associated with a higher-than-average level of intelligence.

Autism, however, more often affects boys. The spectrum of disorders are characterized by social and communication difficulties, along with obsessive behaviors, narrow interests, and a resistance to change.

Baron-Cohen and his team discovered that the two disorders could be linked because they both manifest in rigid attitudes and behavior, narrow interests, and repetitive behavior. They said the word “autism” literally means "exclusive focus on oneself," which also describes the way an anorexic focuses exclusively on his or her weight and physical appearance.

“A preoccupation with the self can present as a failure to empathize, for example, with the stress their behavior causes their family, and this resembles the social difficulties in autism,” the researchers concluded.

Prior research linked the two conditions, but the new study doubled the sample size to achieve higher quality results.

“Clinicians should consider if a focus on autistic traits might be helpful in the assessment and treatment of anorexia,” the researchers concluded. “Future research needs to establish if these results reflect traits or states associated with anorexia.”

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