BIRMINGHAM, Ala.—Abdominal obesity may increase the risk of depression, as well as cancer and cardiovascular disease, according to a new study from the University of Alabama at Birmingham (UAB) published in the American Journal of Public Health.
"We found that in a sample of young adults during a 15-year period, those who started out reporting high levels of depression gained weight at a faster rate than others in the study, but starting out overweight did not lead to changes in depression," said UAB Assistant Professor of Sociology Belinda Needham, Ph.D.
Researchers examined data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, a longitudinal study of 5,115 men and women ages 18-30 that aimed to identify the precursors of cardiovascular disease. The studied data to test whether body mass index (BMI) and waist circumference were associated with increases in depression or whether depression was associated with changes in BMI and waist circumference during a period of time.
CARDIA study scientists weighed and measured the waist circumference and BMI of study participants. The waist circumference was measured to the nearest half centimeter. CARDIA researchers also asked study participants in years five, 10, 15 and 20 to rank their own level of depression.
"Looking at the CARDIA sample data, we found that everyone, as a whole, gained weight during the 15-year period of time that we examined," Needham said. "However, the people who started out reporting high levels of depression increased in abdominal obesity and BMI at a faster rate than those who reported fewer symptoms of depression at year five. In year five, the waist circumference of the high-depression group was about 1.6 centimeters greater than those who reported low depression. By year 20, the waist circumference of the high-depression group was about 2.6 centimeters higher than those who reported lower levels of depression. In contrast, a high initial BMI and waist circumference did not influence the rate of change in symptoms of depression over time.”
Researchers noted there have been reports showing that cortisol, a stress hormone, is related to depression and abdominal obesity. "So, there is reason to suspect that people who are depressed would have higher levels of abdominal obesity versus other parts of the body because of elevated cortisol," Needham said.