Background: Several studies have shown that patients with persistent or severe mental illness are at increased risk for obesity, both from the illness itself and from its treatment. Nevertheless, obesity in these patients could be related to other sociodemographic, psychosocial, and genetic factors. Aim: To explore whether obesity and other physical comorbidities, are more prevalent in longterm psychiatric outpatients as compare to standard population. Design: Cross-sectional study in a rural Community Mental Health Setting, comparing physical and demographic data from psychiatric outpatients with data from the general population of the region, controlling for age, gender, body mass index (BMI) and physical comorbidity. Results: Psychiatric patients were older, with higher BMIs and more chronic diseases. They are more frequently diagnosed with hypertension and hyperlipidemia. However, obesity is related to age, gender and comorbidity, but not to the presence or absence of psychiatric illnesses. Conclusions: Psychiatric patients are more obese than the general population, but it might be related to physical and demographic correlates: age, chronic illness and lifestyle. These factors can be also responsible for their increased risk of hypertension and hyperlipidemia. All those factors could be more relevant than the presence of mental illness itself or its treatment.