Food behavior in the Middle Ages and eating disorders today are both associated with psychological factors but very different ones. The food behavior of holy fasting and holy feasting in the Middle Ages that Bynum attributes to women was spurred by the psychological motivation of spiritual attainment. These women sought to attain unity with Christ and his suffering. They developed stigmata and fluid weeping that paralleled Christ's suffering during Crucifixion.
On the other hand, food disorders that occur today (anorexia nervosa and its subcategory bulimia nervosa and binge eating without bulimia) are spurred by a psychological motivation to alter a distorted body image and are seen as a subconscious expression of stress release of socio-culturally created stress. This is seen as similar to the epidemic of women's "hysteria" in the 18th and 19th centuries that was spurred by issues of women's appearance and role and that dissipated at the turn of the 20th century as new roles and body images were emphasized.
One thing Middle Ages food behaviors and today's eating disorders are theorized to have in common is an underlying issue of empowerment. This issue mostly concerns women in both eras because (1) ascetic men did not value holy feasting and fasting in the same manner, as seen in the hagiographic records Bynum investigated, and (2) mostly women suffer from eating disorders (though not exclusively) in a pursuit of thinness.
Women in the Middle Ages found empowerment through spirituality related food behaviors by (1) defying socio-cultural expectations as well as by (2) accusing and condemning male clerics by rejecting the Eucharist as impure.
It is theorized that eating disorders of today may offer women a opportunity to assert their own identity though this is highly arguable since there is (1) no positive impact on the male dominated society that is compelling the obsession with a distorted body image. Similarly, there is (2) no positive impact on socio-cultural connections as there was for the holy women ascetics of the Middle Ages.
Holy feasting and holy fasting women in the Middle Ages made a wide religious and socio-cultural contribution by ridding congregations of corrupt clergy and by performing miracles of healing, while women with eating disorders today only deteriorate socio-cultural relationships as they drag themselves to potentially fatal precipices of compliance with patriarchally superimposed expectations and false images of distorted female ideals.