The phenomenology of compulsive eating has encouraged comparisons with addictive behaviours and this has suggested that similar underlying processes might be at work. In this paper it is argued that craving for food, preoccupation with eating and loss of control over food intake represent a natural psychobiological adaptation to sub-optimal weight and food deprivation. Compulsive eating is therefore best understood in terms of a conflict between a biologically derived drive for food and a culturally derived drive for thinness. Both of these processes have their parallels in the maintenance of dependency disorders. The crucial difference however is that the urge to eat is biologically adaptive, and recovery from compulsive eating depends upon relaxing restraint.