Many psychiatric disorders are associated with obesity and include mood disorders, anxiety disorders, personality disorders, attention deficit hyperactivity disorder, binge eating disorders, trauma, bipolar disorder, and schizophrenia. According to National Obesity Observatory, there is evidence that both obesity and mental health disorders take up a significant portion of the global burden of disease. The bidirectional nature of obesity and mental illness indicates the importance of screening all persons being treated for either obesity or mental illnesses be screened for the other. Failure to do so may decrease the effectiveness of treatment for each one individually.