The relationship between eating and emotion has always interested researchers of human behavior. This relationship varies according to the particular characteristics of the individual and according to the specific emotional state. We consider findings on the reciprocal interactions between, on the one hand, emotions and food intake, and, on the other, the psychological and emotional consequences of losing weight and dieting. Theories on the relationship between emotions and eating behaviors have their origin in the literature on obesity. The psychosomatic theory of obesity proposes that eating may reduce anxiety, and that the obese overeat in order to reduce discomfort. The internal/external theory of obesity hypothesizes that overweight people do not recognize physiological cues of hunger or satiety because of faulty learning. It thus predicts that normal weight people will alter (either increase or decrease) their eating when stressed, while obese people will eat regardless of their physiological state. The restraint hypothesis postulates that people who chronically restrict their food intake overeat in the presence of disinhibitors such as the perception of having overeaten, alcohol or stress. These theories are examined in the light of present research and their implications on eating disorders are presented.