The relationship between body weight and blood pressure, total serum cholesterol, triglycerides, uric acid and glucose was investigated in 203 psoriatic patients in comparison with 904 healthy controls. In the psoriatic patients, these parameters were clearly related to their body weight. Those psoriatic patients of normal weight exhibited lower mean values of all the parameters compared with overweight psoriatic patients while they did not differ from control subjects of normal weight. Our results suggest that only overweight psoriatic patients exhibit the metabolic abnormalities frequently reported in the literature, while psoriatic patients of normal weight do not differ from the general population in this respect.