Anorexia nervosa, seasonality, and polyunsaturated fatty acids.

Anorexia nervosa is a serious neurobehavioral disorder marked by semistarvation, extreme fear of weight gain, frequently hyperactivity, and low body temperature. The etiology remains unknown. We present a speculation that a primary causative factor is that polyunsaturated fatty acids are skewed to prevent oxidative damage in phospholipid membranes. This causes a change in the trade off of oxidation protection vs homeoviscous adaptation to lower temperatures, which sets off a metabolic cascade that leads to the rogue state of anorexia nervosa.