Stronger Obesity, Depression Link in Young Women

The connections between obesity and depression in young women are strengthened by the results of a new study, which found young adolescent women who are depressed are at risk for becoming obese as they age and the risk of becoming depressed as young adults is increased in late-adolescent women who are obese.

“Adolescence is a key developmental period for both obesity and depression, so we thought it significant to look at the onset of these disorders at an early age,” said Naomi Marmorstein, PhD, Professor of Psychology at Rutgers University–Camden in New Jersey.

Results have been mixed in previous research looking at the connections between depression and obesity. Some studies have found that depression and obesity go hand-in-hand; others have found no connection. The new study improved on past research by focusing on the onset of each disorder.

Dr Marmorstein and colleagues assessed a statewide sample of more than 1500 males and females in Minnesota over a period of more than 10 years. Participants were assessed at ages 11, 14, 17, 20, and 24 years by using height and weight measurements and clinical, interview-based diagnosis of major depressive disorder. The researchers looked specifically for onsets of either disorder by age 14 years, between 14 and 20 years, and between 20 and 24 years.

The results show that depression occurring by early adolescence in females predicts obesity by late adolescence. In addition, obesity that occurs by late adolescence in females predicts the onset of depression by early adulthood.  No significant associations between the 2 disorders across time were found in males.

Depression can lead to obesity through an increased appetite, poor sleep patterns, and lethargy; obesity can cause depression because of weight stigma, poor self-esteem, and reduced mobility. “When a person is young, she is still developing eating and activity patterns, as well as coping mechanisms. So if she experiences a depressive episode at age 14, she may be more at risk for having an onset of unhealthy patterns that persist,” Dr Marmorstein said.

An obese child also may be more susceptible to negative societal messages about obesity or teasing, which could contribute to depression. Adolescents starting to establish relationships may become self-conscious, and teasing can be particularly painful, she noted.

Dr Marmorstein recommended that clinicians aim prevention efforts at both of these disorders at the same time when one of them is diagnosed in adolescents, which might help decrease their prevalence and comorbidity. “When an adolescent girl receives treatment for depression, the clinician might consider incorporating something relating to healthy eating and activity,” she said. “Exercise can assist in the treatment of depression to begin with, so it seems like a good reason to combine prevention efforts for both depression and obesity.”

Why no associations between the 2 disorders were found in male adolescents is unknown. However, Dr Marmorstein hypothesizes that it could be a result of different developmental processes leading to obesity and depression.

The researchers published their results in the January 31, 2014 issue of the International Journal of Obesity.