Activity Based Anorexia: A Bio-Behavioral Model of Anorexia with Unique Treatment Implications

These experiments used an animal model to examine potential treatments designed to eliminate activity-based anorexia. Activity-based anorexia is behavior characterized by high levels of activity, low levels of food consumption, and extreme weight loss. During baseline, rats were given free access to food, water, and a locked running wheel for 24 hours daily. Rats’ food consumption in grams and weights in grams were measured each day. Following baseline, rats were given access to food for one hour per day and access to an unlocked running wheel for the remaining 23 hours of the day. The experiment involved a comparison group for recovery time and two interventions (different groups of rats), which have the potential to provide useful data for designing treatments for human anorexics. During the comparison group, the running wheels were locked, rats were given free access to food, and the amount of time for rats to return to baseline weight was measured. During the first intervention, rats were given access to the running wheel contingent upon eating adequate amounts of food (calculated based on amounts eaten during baseline). During the second intervention, rats were provided limited access to the running wheel following adequate food consumption (rats were not allowed to run 3 hours prior to eating). Results showed that rats lost weight (from 14% to 34% of their baseline weights) during the procedure. Once subjects were removed from the procedure, recovery time was 6 days for rats who showed a strong weight loss effect (more than 30% of baseline weights) and ranged from 1 to 5 days for rats who showed a weaker weight loss effect. Results of the treatment phases are pending.