Antidepressants May Contribute To Obesity
June 18, 2013

Obesity Risk Higher When Stressed And On Antidepressants

Rebekah Eliason for — Your Universe Online

Stress and high fat diets are common factors that cause weight gain, but researchers at John Curtin School of Medical Research have linked short-term antidepressant use to long-term weight gain as well.

"Our study suggests that short-term exposure to stress and antidepressants, rather than a high-calorie, high-fat diet alone, leads to long-term body weight gain, accompanied with increased bone and spleen weights," said study lead author Suhyun Lee, a PhD candidate in the medical sciences at the John Curtin School of Medical Research at the Australian National University in Canberra, Australia.

Antidepressants are among the most common prescriptions written every year. More than 1.5 million prescriptions were written for antidepressants in the United States during 2009. Australia wrote a staggering 12 million prescriptions for antidepressants during 2008.

Worldwide, the obesity rate of adults is rising in developed countries. In the United States and Australia, two-thirds of adults are either obese or overweight. Risks for heart disease, along with many other diseases, are greatly increased in people who are obese or overweight.

Weight gain is known to be a main side effect of antidepressants with some patients reporting a 7 percent increase in weight from the start of treatment.

In this study, male rats that had experienced stress-induced weight gain were treated with the antidepressant fluoxetine and then compared to a control group. Animals treated with antidepressants experienced greater bone and spleen weights compared to those in the control group.

Along with weight, behavior was compared between the treated group and control group. Rats that had received fluoxetine displayed significantly lower anxiety after stressful periods compared with those in the control group.

Lee explained, “These findings may implicate different pathophysiological mechanisms in stress and antidepressant related obesity when compared to obesity that is solely diet-induced.”

This study was funded by the John Curtin School of Medical Research, Australian National University and was presented Sunday at The Endocrine Society's 95th Annual Meeting in San Francisco.