Fat people aren't more jolly. In fact, researchers say obesity is strongly linked with depression and other mood disorders.

A study of more than nine-thousand adults found mood and anxiety disorders, including depression, were about 25 percent more common in obese people than in non-obese. But the study found obese people about 25 percent less likely to abuse drugs or alcohol than their more slim peers.

The study is in the July issue of Archives of General Psychiatry.

A National Institute of Mental Health scientist says the results show "the jolly fat person is more a figment of our imagination than a reality." The institute paid for the study.

About one third of American adults are obese. Depression affects about ten percent of Americans.