WEDNESDAY, Aug. 5, 2009 (HealthDay News) -- Social stress may cause the body to deposit more fat in the abdomen, which increases the risk of heart disease, a new study suggests.
The findings could lead to new ways to combat rising rates of obesity in the United States and other Western nations, according to principal investigator Carol A. Shively, a professor of pathology at Wake Forest University School of Medicine.
"Much of the excess fat in many people who are overweight is located in the abdomen, and that fat behaves differently than fat in other locations. If there's too much, it can have far more harmful effects on health than fat located in other areas," she said in a Wake Forest news release.
In the study, designed to see how social status affects the development of heart disease, female monkeys were fed a Western-style diet that contained fat and cholesterol. The monkeys were housed in groups and naturally established a pecking order from dominant to subordinate.
The researchers noted that the subordinate monkeys were not included in group grooming sessions as often as dominant monkeys, and were often the target of aggression.
The subordinate monkeys in this study then developed more fat in the abdominal cavity than other monkeys.
Social subordination causes the release of stress hormones that promote fat accumulation in the abdomen, the researchers said. This abdominal (visceral) fat promotes the build-up of plaque in blood vessels that leads to heart disease, the leading cause of death worldwide.
The study appears in the current issue of the journal Obesity.
Shively said the findings reinforce the wisdom of healthy eating, regular exercise and handling stress well.
The U.S. National Heart, Lung, and Blood Institute outlines heart disease risk factors.