An evaluation of trace metals, vitamins, and taste function in anorexia nervosa

Trace metals, vitamins, and other biochemical parameters were measured in 30 female patients hospitalized for anorexia nervosa with the aim of relating them to taste function, biochemical changes, and clinical signs found in this illness. Plasma zinc (71.9 +/- 14 microgram/100 ml; P < 0.01), urinary zinc (129.5 +/- 121 microgram/24 hr), and copper (84 +/- 17 microgram/100 ml; P < 0.001), were depressed, whereas zinc and copper content of hair was normal. Anorexia nervosa patients showed hypogeusia, with the bitter and sour taste most severely affected, however plasma zinc levels did not correlate with taste recognition scores. Patients showed hypercarotenemia (214 +/- 129 microgram/100 ml; P < 0.01) with normal plasma vitamin A and retinol-binding protein levels. Total iron binding capacity was depressed (261 +/- 62 microgram/100 ml; P < 0.001) in contrast to plasma iron, ceruloplasmin and folic acid, which were normal. In nine patients, who were retested before discharge, taste function improved; plasma zinc, copper, and total iron binding capacity levels increased whereas plasma carotene and cholesterol decreased to normal levels. It is concluded that the observed zinc, copper, and iron binding protein deficiencies, and hypogeusia, reflect the self-imposed nutritional restriction of anorexia nervosa patients. Zinc and other micronutrients released from catabolized tissue along with vitamin intake may mitigate against more severe deficiency states in anorexia nervosa.