Fluid restriction in anorexia nervosa: A neglected symptom or new phenomenon?

Objective: The deliberate restriction of fluids to control weight is even m ore dangerous than food restriction since it results in several serious med ical complications. However, there has been scant attention given to the an orexia nervosa patient's manipulation of fluids. It is our clinical impress ion that fluid restriction in this illness is more common than previously t hought. Method: We summarize the demographic and clinical features of six c ases of anorexia nervosa and one case of eating disorder not otherwise spec ified (ED-NOS) (subthreshold anorexia nervosa), where fluid restriction was a major behavioral problem. We then decribe two of the anorexia nervosa ca ses in more detail. All were treated at a dieting disorders unit affiliated with the University of Sydney. Their preadmission history, psychological a nd physical status on admission, results of physical investigations, the be ginning of the fluid restriction, fluid and food intake throughout treatmen t, and the resolution of the fluid restriction were assessed. Results: Patt erns emerged in the relationship between eating and drinking. In all cases, food restriction was severe prior to the onset of fluid restriction but, n otably, fluid intake recommenced prior to food intake. The reasons given by patients for restricting fluid were that it contained calories and that it made them feel full. Most anorexic patients equate feeling full with "feel ing fat." Furthermore, they feel fully in control when they restrict fluid as well as food and this produces a strong motivation to maintain the behav ior. Discussion: The cases illustrate the insidious nature and serious cons equences of fluid restriction and the difficulties managing dieting-disorde red patients who undertake it. Careful attention must be given to assessmen t and clinicians should be aware of fluid restriction as an important aspec t of anorexic behavior. (C) 1999 by John Wiley & Sons, Inc.