CYP3A4 and anorexia nervosa: In a recent study on the correlation between body weight and CYP3A activity, [12] Sandvik et al. reported that the enzyme activity of CYP3A4 was higher in patients with anorexia nervosa compared to a control group consisting of individuals with normal weight, and that CYP3A4 activity was negatively correlated with body weight [13].