OPTIWIN is a year-long study, designated to evaluate the effectiveness of the OPTIFAST® weight loss program, in comparison with a standard-of-care, reduced energy, food-base diet (modified version of Diabetes Prevention Program, DPP) and lifestyle intervention among adults with a BMI higher than 30.

Study objectives: To determine the effectiveness of a structured multidisciplinary non-surgical obesity therapy program on the basis of a temporary low-calorie-diet (Optifast 800 Kcal) for 12 weeks, and additional intervention modules to enhance nutritional education, to increase physical activity and to modify eating behaviour.