Sun Exposure and Anorexia Nervosa: A Potential Environmental–Biological Interaction?

Objective

Despite first being described in 1888, anorexia nervosa continues to be the deadliest of all psychiatric illnesses. Although efforts have been made to elucidate the aetiological factors involved in the illness, little progress has been made in uncovering what contributes to the development and maintenance of anorexia nervosa. A particular shortcoming of the current literature has been the investigation of interactions between environmental and biological factors. One such interaction which has yet to receive attention in anorexia nervosa is that of sun exposure. Exposure to the sun—including levels of ultraviolet radiation (UVR) and vitamin D—in the pathogenesis of other mental illnesses has long been investigated (with lower levels of vitamin D reportedly involved in the pathogenesis of conditions such as schizophrenia, for example) but is yet to be explored in anorexia nervosa.

Conclusions

The current paper proposes a novel hypothesis for the potential contribution of reduced sun exposure in the aetiology of anorexia nervosa for future investigation, and possible mechanisms for how this relationship may operate.