*The following is excerpted from an online article posted on HealthDay.
As if it isn't tough enough being an overweight kid, a new study shows it could have long-lasting repercussions for psychological health, too.
When compared with normal-weight kids who become overweight adults, overweight or obese youth in the study faced three times the risk of depression in adulthood, the research found.
And, that risk was more than four times greater if they were overweight or obese in both childhood and adulthood, the investigators reported.
The study doesn't prove that obesity causes depression. But the finding confirms earlier reports of an increased depression risk in young people who are obese, the study authors said.
"Overweight children do have a higher risk of developing major depressive disorder over their lifetime compared to normal-weight children," said study author Deborah Gibson-Smith.
More than one in three children in the United States is overweight and nearly one in five is obese, according to data from the U.S. Centers for Disease Control and Prevention.
The relationship between obesity and depression is complex, said Gibson-Smith, a Ph.D. student at VU University Medical Center in the Netherlands.
For example, people who fail to conform to ideal body weight may have lower self-esteem, and "low self-esteem has been associated with subsequent depression," she observed.
It's also possible their vulnerability for both overweight and depression is partly due to a "shared genetic risk," she added.
Gibson-Smith and colleagues used data from nearly 900 Icelanders born between 1907 and 1935 who participated in a population study that followed on an earlier, larger study.
Participants in the 2002 to 2006 follow-up study were 75 years old, on average. Data on childhood weight and height were obtained from school records, while midlife data came from the earlier study.
The investigators found that excess weight in childhood is a stronger predictor of later depression than being overweight in midlife.
The findings were presented at the European Congress on Obesity, in Porto, Portugal.