Stress and Depression May Trigger Obesity

(February 24, 2010) - Young girls may be more susceptible than boys to the hormones that are released during stress. (Read about "Stress") Depression (Read about "Depressive Illnesses") raises stress hormone levels in adolescent boys and girls but may lead to obesity (Read about "Obesity") only in girls, according to researchers.

"This is the first time cortisol reactivity has been identified as a mediator between depressed mood and obesity in girls," said Elizabeth J. Susman, one of the researchers. "We really haven't seen this connection in kids before, but it tells us that there are biological risk factors that are similar for obesity and depression."

Cortisol, a hormone, regulates various metabolic functions in the body and is released as a reaction to stress. Researchers have long known that depression and cortisol are related to obesity, but they had not figured out the exact biological mechanism.

Although it is not clear why high cortisol reactions translate into obesity only for girls, scientists believe it may be due to physiological and behavioral differences - estrogen release and stress eating in girls - in the way the two genders cope with anxiety. (Read about "Anxiety")

"The implications are to start treating depression early because we know that depression, cortisol and obesity are related in adults," said Susman.

If depression were to be treated earlier, she noted, it could help reduce the level of cortisol, and thereby help reduce obesity.

"We know stress is a critical factor in many mental and physical health problems," said Susman. "We are putting together the biology of stress, emotions and a clinical disorder to better understand a major public health problem."