Self-determination is the ability to define one's own goals in life, to decide how to achieve them and to begin the process of change for one's own sake rather than to please other people. Self-determination is associated with enhanced learning, greater interest, more persistence, better performance, higher self-esteem, increased life satisfacion and enhanced health. It could also help protect young women against social pressures relating to body image and the endorsement of damaging ideas about thinness and obesity which in turn could lead to them going on to develop eating disorders. A study of 447 students in Ottawa found that women's general level of self-determination was linked to an autonomous regulation of eating behaviours (i.e. the young women felt in control of their eating) and made people less likely to restrict what they ate or enter into a cycle of dieting and bingeing.
Pelletier, Luc G. and Dion, Stephanie C. - An examination of general and specific motivational mechanisms for the relations between body dissatisfaction and eating behaviors Journal of Social and Clinical Psychology March 2007, 26(3), 303-333