Obesity, a major problem worldwide, is more prevalent among people with schizophrenia. This study examined the effect of behavior intervention, nutritional information and physical exercise on the body mass index (BMI) and weight of people who were hospitalized with persistent DSM-IV schizophrenia and schizoaffective disorders. Fifty nine inpatients with a BMI greater than 25 participated, (28 intervention group; 31 control group). Significant reductions in BMI and weight were observed in the intervention group after 3 months and were maintained 1-year post study [F(1,52) = 6.1, p = .017) and F(1,52) = 3.7, P = .006, respectively]. If provided with adequate information and an appropriate framework, people with persistent schizophrenia can significantly reduce BMI and weight and maintain the loss.