Study Shows Link Between Obesity And Depression

A U.S. study has found that obesity is linked with a 25 percent increase in odds of developing psychiatric disorders, such as depression, bipolar disorder and panic disorder.

The study, published in the Archives of General Psychiatry's July issue, of more than 9,000 adults found that mood and anxiety disorders including depression were about 25 percent more common in the obese people studied than in the non-obese.

It also found that there were no significant differences between the sexes, but the relationship between obesity and mental illness was strongest in people with more education and higher incomes.

Obesity has always been linked to many physical problems including heart disease, stroke, type 2 diabetes and arthritis, but there has been less research to date on its psychiatric consequences.

This study is the first major study to look at an association with psychiatric consequences.

According to Dr. Greg Simon, lead author, "It's almost certain that the association works in both directions. Understanding the connection between obesity and depression is an important public health issue because both of these conditions are so common and have a significant impact on our health care systems."

He studied along with his colleagues at the Group Health Cooperative, Seattle.

Of all the participants, 6,795 had a body mass index (BMI) of less than 30 and 2,330 had a BMI of 30 or more and were therefore considered obese.

Those who were obese had a higher prevalence of mood and anxiety disorders and a lower prevalence of substance abuse disorders over their lifetimes, said the study published in the July issue of Archives of General Psychiatry.

"The estimated prevalence of lifetime mood disorder in those with BMIs below 30 and in those with BMIs 30 or higher translates to a population-attributable risk of 24 percent, which indicates that nearly one-quarter of the cases of obesity in the general population are attributable to the association with mood disorder," said one of the researchers.

Depression often causes people to abandon regular activities. Some medications used to treat depression and other disorders can lead to weight gain. On the other hand, obesity is seen as a stigma at social level, and overweight people are often looked down and mocked. This in turn boosts their urge to gorge themselves on food. So whether depression leads to obesity or the other way round, in both conditions, affected people find themselves caught in an impossible cycle.