Anorexia nervosa (AN) is a severe psychiatric condition primarily affecting young women, and AN has the highest mortality rate among psychiatric disorders. AN continues to be a disorder refractory to psychological or pharmacological treatment. An innovative approach arises from research in rats simultaneously placed on a restricted feeding schedule and given free access to an activity wheel. The detrimental effects of combining diet and exercise in rats can be reversed by a manipulation of ambient temperature (AT). Warming animals exposed to these experimental arrangements reverses running activity, preserves food intake, and enables rats to recover from acute weight loss. This represents a strong preclinical evidence that provides a rationale for a translational approach for the treatment of AN. However, heat application to AN patients was already a recommendation made by William Gull in his seminal paper on AN disorder. A historical perspective of supplying heat to AN patients reviews the circumstances and foundation of this practice. The manipulation of AT in activity-based anorexia (ABA) rats has ended with a period of neglect of AT that parallels the complete neglect of the role of AT in the human AN disorder, either as a risk factor, as a modulating factor in the course of the disorder, or in terms of its utility in the treatment of AN.
The case for warming as an adjunctive treatment for AN patients is based on strong experimental evidence gathered from
research on animals with Activity-Based Anorexia (ABA). We posit that the beneficial effect of heat results, at least in
part, from heat blocking the vicious cycle that hyperactivity plays on AN. Hyperactivity decreases caloric intake by
interfering with feeding and increases energy expenditure through excess motor activity which in turn increases
emaciation that further strengthens anorexic thinking.
Disparate treatments, placebos, and treatments as usual have similar efficacy for anorexia nervosa. A parsimonious dissection of the this issue with Occam’s razor will necessarily challenge the assumptions on which the diagnosis of anorexia nervosa is based. One such assumption is the role of body-image disturbance, which became a key diagnostic symptom of anorexia nervosa in the literature almost five decades ago, long before any empirical evidence was gathered about this symptom. Body-image disturbance is far more represented among therapists and in the hypotheses of researchers than in the minds of patients. Concerns about body image might not stem exclusively from the patient’s underlying motives for refusing food, but might be in part a by-product of the “psychiatrist zeal in searching out motives”, as first recognised before the inclusion of body-image disturbance in the conceptualisation of anorexia nervosa. Body-image disturbance and weight and shape concerns are the result of an acculturation process spread through the therapeutic milieu and the mass media.