BackgroundDespite extensive clinical concern about rates of obesity in patients with schizophrenia, there is little evidence of the extent of this problem at a population level.AimsTo estimate levels of obesity in a national population sample by comparing patients with schizophrenia with matched controls.MethodWe calculated levels of obesity for each patient with schizophrenia from the national Primary Care Clinical Informatics Unit database (n=4658) matched with age, gender and neighbourhood controls.ResultsWe demonstrated a significant increased obesity hazard for the schizophrenia group using Cox regression analysis, with odds ratio (OR) of 1.94 (95% CI 1.81–2.10) (under the assumption of missing body mass index (BMI) indicating non-obesity) and OR=1.68 (95% CI 1.55–1.81) where no assumptions were made for missing BMI data.ConclusionsPeople with schizophrenia are at increased risk of being obese compared with controls matched by age, gender and practice attended. Priority should be given to research which aims to reduce weight and increase activity in those with schizophrenia.