The purpose of this study was to assess the evolution in the nutritional situation of patients diagnosed with anorexia nervosa in the Clinical Nutrition Service between January 1 1989 and December 31 1991. Twenty-eight admitted patients (4 men and 24 women) and 38 outpatients (3 men and 35 women) were monitored, with an age of 22.4 +/- 6.4 years and average evolution time of the illness of 3.8 +/- 5 years. Nutritional state was evaluated with anthropometric, biochemical and immunological parameters. Following nutritional therapy, malnutrition and BMI (Body Mass Index) improved significantly over the initial evaluation in all patients, whether admitted or outpatients. All anthropometric parameters improved significantly during the period of treatment of admitted patients, but AMC (arm muscle circumference) rose only in outpatients. An unrestricted diet plus nutritional counselling was the most-used therapeutic procedure in outpatients while most of the admitted patients required dietary supplements. Calorie malnutrition is very common in patients diagnosed with anorexia nervosa: vitamin or trace element deficiencies are very infrequent. Nutritional therapy, suitably coordinated with psychotherapeutic treatment, is effective, enhancing both the nutritional state and anomalous dietary habits.