If you are under chronic stress, feel like everything you eat goes directly to your belly, it may be truer than you think. When researchers at the Wake Forest University fed trial monkeys a typical American diet which was high in fat and cholesterol, they gained weight. But those who were socially stressed developed much more belly fat, a known risk factor for heart disease.
Although the study was conducted especially on monkeys, the researchers say the results would be very similar in humans and could lead to new ways of containing the ever growing obesity epidemic in American and other western nations. Lead researcher Carol A Shively, a professor of pathology at Wake Forest claims ” we are in the midst of an obesity epidemic. Much of the extra fat in many people who are overweight is centered i the abdomen area, and that fat behaves differently than fat in other places on the body. If there is too much, it can have far more harmful effects on health than fat located in other areas.”
Shively and colleagues studied female cynomolgus monkeys to better understand the role social stress plays in the development of hear disease. Monkeys that were fed a high fat and cholesterol diet and housed in a natural setting, showed subordinate and dominate personalities. The team observed that the subordinate monkeys were less likely to be invited to join in group activities, such as grooming, and were often targets of aggression.
While all of the monkeys did gain weight, CT scans noticed more abdominal or visceral fat in the socially stressed monkeys than the others. Cortisol, a stress hormone which causes belly fat to accumulate and makes individual fat cells get larger was found in the monkeys with a lower social status. And when the researchers looked at the animals’ arteries, they found plaque blocking those of the stressed monkeys. “The monkeys that have excess abdominal fat have the metabolic syndrome, just like people with a lot of abdominal fat,” Shively says. “When you have lots more fat in visceral fat cells and all the characteristics of the metabolic syndrome, each of these things promotes atherosclerosis.”
Female monkeys, like women, have a natural protection against heart disease. But the monkeys with high social stress and larger amounts of abdominal fat had ovaries that produced fewer protective hormones, destroying this female protections. “Suppressed ovarian function is a very serious condition in a woman,” Shively said. Compared to the unstressed monkeys, the researchers found that the stressed monkeys had abnormal menstrual cycles and therefore much less likely to ovulate. “We need to take a closer look at the ovarian function of obese women,” she said. “They might not be producing enough hormones to maintain adequate health.”
Reinforced basic health advice: watch what you eat, exercise regularly and try to manage the stress in your life is what this study indicates. Other experts who reviewed the data suggest that if you are planning to begin a weight loss program, you should consider including some form of stress reduction, such as a stress management or meditation class as these are very beneficial areas to improve.
Ninety-nine percent of people who lose weight will lose it in the abdominal region before anywhere else. Researchers also have found that abdominal fat cells aren’t just dormant energy waiting to be burned up. The cells are active, producing hormones and type 2 diabetes; others can produce estrogen after menopause, which may increase your breast cancer risk. Researchers are still sorting out how the excess hormones affect overall health.