A study, led by Michigan State University (MSU) researchers, enlisted more than 300 female twins between the ages of 12 and 22 to identify the role genes play in making some women more prone to "thin-ideal internalisation" - the urge to be slim.
The results from identical twins who share 100 per cent of their genes were contrasted against fraternal twins, who only share half of the same genetic makeup.
It was found that identical twins have closer levels of thin-ideal internalisation than their fraternal counterparts, suggesting genetics play a core role in who is susceptible to the pressure to be thin - which is often cited as a cause of eating disorders.
Moreover, the role media images played when displayed to each twin seemed to be less of an influential factor than the experiences they underwent separately, such as weight-loss dance classes or being part of a friendship group that is focused on size.
"We were surprised to find that shared environmental factors, such as exposure to the same media, did not have as big an impact as we expected," explained lead study author Jessica Suisman.
"The take home message is that the broad cultural risk factors that we thought were most influential in the development of thin-ideal internalisation are not as important as genetic risk and environmental risk factors that are specific and unique to each twin."
MSU professor of psychology Kelly Klump stressed that a broad range of factors can contribute to the development of eating disorders, with this logic also applicable to the ways in which women "buy in" to pressure to be thin, taking into account genetics and environmental factors.
According to the NHS, the most common eating disorders are anorexia nervosa, bulimia and binge eating, with one in 250 women affected by anorexia, compared to one in 2,000 men.
