A new study shows that those children who develop anorexia at some point are programmed into the wombs of their mother's hormones, reports BBC News.
Usually, this eating disorder occurs more often in women than in men, but a university in Sussex has found that men who have a twin sister are more exposed.
These data suggest that hormones released to help women's development may be the answer. Of course, specialists point out that other factors in childhood and adolescence remain as important as before.
It is still unclear why women are more prone to this kind of affection than men. Some experts believe that stress in modern society is partly to blame, while others look at brain changes in the early part of life.
Twin pregnancy research is a way to examine the factors involved because the most important period for brain development is the months of pregnancy.
The new study looked at information gathered from thousands of twins born between 1935 and 1958. Overall, as expected, it was found that female twins are more prone to anorexia than male twins. The only exception appeared for twins of different sex when the male one proved to be more prone than the female one.
Researchers believe that the most likely cause is steroid sex hormones released in the womb during pregnancy.
A plausible explanation for this phenomenon would be that during pregnancy with female girls there is a substance, probably hormonal, that increases the risk of developing anorexia nervosa at maturity. Because the male fetus from a twin pregnancy is exposed to this substance, it presents an increased risk.
Experts say that this study must be completed by others to analyze other factors such as the perception of physical appearance in childhood and adolescence.
December 4, 2007