Healthy people eat when they are hungry and stop when they are satisfied.
Those with eating disorders do not have the same contact with their real
hunger and satisfaction feelings. They eat or starve when their feelings
are unbalanced. It is difficult for them to separate hunger from other
unpleasant sensations. A bulimic might also eat compulsively when starved,
because of previous starvation or vomiting.
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When different feelings cannot be separated, the necessary information for
managing the underlying problems properly is unobtainable. In normal
people, thoughts, feelings and physical signals tell us what must be done
in order to function as well as possible. Those who get the wrong
information become confused and can't use their knowledge and feelings in
order to manage their problems correctly.
More information
How do you learn to recognize your real feelings?