Obesity appears to increase the risk for some mental illnesses, including mood disorders such as depression, bipolar disorder and anxiety disorders, according to a study in last month’s Archives of General Psychiatry. But it may decrease the risk for alcoholism and drug abuse.
The findings were based on a national survey of more than 9,000 men and women. More than 2,300 had a body mass index – a measure of weight relative to height – of 30 or higher, which is considered obese.
The obesity-psychiatric illness link was strongest among whites and those with the highest education levels.
Earlier studies have suggested obesity may be linked with mood disorders. And several surveys “have found associations between obesity and depressive symptoms, history of depression, and measures of psychological distress,” according to the study.
Lead study author Gregory Simon, a psychiatrist with Group Health Cooperative (an HMO based in Washington state), said “it’s likely that the relationship goes in both directions,” meaning obesity may up the risk for psychiatric illness and vice versa. He said there could be both social and biological reasons for the link, noting that some drugs used to treat mental illness can cause weight gain.
Karen Johnson, associate chairman of psychiatry at Washington (D.C.) Hospital Center, urged caution in interpreting the findings, saying further study is still needed.
