One hundred overweight adult patients were subjected to a hypocaloric diet with periodic controls during a one year observation period. During the first 4 months, 98% of the patients adhered to the dietary regimen, with an initial mean percentage loss of body weight of 9.3% for the females and 8.9% for the males. The weight loss was more conspicuous during the first two months of the diet therapy and in patients with an initially higher BMI. With time, the rate of drop-out from the diet therapy increased, which resulted in a follow-up of 49% and 87% of cases at 6 and 12 months respectively, with no significant differences between the two sexes. The drop-out phenomenon resulted to be more frequent in patients with an initially lower BMI.