Studies are now showing that a history of mental illness may increase the risk of a person becoming obese. In return, obesity may increase a person’s chances of developing a psychiatric disorder. As reported in Psychiatry Advisor, the link between psychiatric problems and obesity include physical inactivity, poor self-image, the social stigma involved in being overweight and the biological problems caused by obesity.
Several studies have documented a disproportionate number of patients who have mental illnesses and are obese, compared to the general population. A study of patients receiving psychiatric care in Maryland discovered that their body mass index (BMI) was nearly twice those in the comparison group. And, according to the Arizona Department of Health Services, people who have mental illness die 25 years earlier due to obesity-related conditions than those without mental illness.
Studies conducted by the UK’s National Obesity Observatory and at the Texas Health Science Center are two of the many research programs that have confirmed that those who are obese face a greater risk for depression. Age and gender can determine how strong that risk is. A South Africa study found that young women who were obese were most at risk for mental illness.
Race is another factor in the link between mental illness and obesity. A University College London study found that white girls were more affected by being overweight than were those from African groups, since girls in the latter category did not face such a strong social stigma in their society.
Medication is one of the factors that explains the increased risk of obesity in those with mental illness. Psychotropic drugs not only contribute to weight gain, but also cause changes in the body’s sensitivity to insulin. Metabolic syndrome, which results from insulin resistance because of increased abdominal fat, is frequently found in people with schizophrenia.
A study published in 2007 in the American Journal of Managed Care noted that the psychological problems that mentally ill patients experience exacerbate the weight gain caused by psychiatric medications, particularly since nearly all of those medications cause weight gain.
The link between obesity and mental illness, however, may be too simplistic, since psychiatric disorders, including attention deficit disorder, depression and post-traumatic stress disorder can lead to “comfort eating,” resulting an weight gain. People with these conditions may also lose interest in preparing healthy meals and exhibit impulsive eating habits. Weight gain can also be caused by the emission of cortisol, the stress hormone, during times of stress.
Obesity dramatically affects both physical and mental health, which can lead to full-blown mental illness due to physical ailments and poor self-image. Conversely, psychiatric medications can cause obesity.