People get fat from eating too much and exercising too little. At least that's the most widely held explanation for the growing obesity crisis around the world. But it's not that simple, says Dr. Achim Peters, a professor of neurology at the University of Lübeck in Germany and author of "The Selfish Brain -- Why Our Brain Sabotages Dieting and Resists the Body" (Ullstein, 2011).
The worldwide obesity epidemic is in truth a stress epidemic, and unhealthy weight gain is just one of the ills that plague an increasingly stressed population trying to cope with the ever-growing demands of modern life, he says in an interview with the German news magazine "Der Spiegel."
In reality, weight issues are often rooted in socio-economic difficulties like job loss, poverty, rising food prices and other existential uncertainties, he says. It puts tremendous pressure on people. Stress-producing situations can be immensely damaging to our health, especially when they persist over long periods of time with no reprieve in sight.
Dr. Peters is best known for the "Selfish Brain Theory," which he developed together with an interdisciplinary team of scientists over a decade ago when researching the origins of obesity. In essence, the theory describes how the brain takes care of its own needs first when regulating energy distribution throughout the body. It is "selfish" in the sense that it always wins out in any competition for energy resources, at the expense of all other organs if necessary.
In times of stress, the brain spends particularly high amounts of energy, which requires an increase in food intake. During acute stress situations, a rapid spike in energy demand is natural and not harmful. It is different when stress is prolonged. Then it can become a chronic state and as such quite dangerous.
To shed some light on these dynamics, it is important to understand our body's hormonal responses to stress. Energy in the body is regulated and mobilized by a hormone called cortisol. Cortisol selects the right type and amount of energy to meet the body's demands when responding to a particular situation. Cortisol is also responsible for mobilizing energy by tapping into the body's fat stores and moving it to where it's most needed, primarily in the brain.
Studies in animals and humans have shown that heightened secretion of cortisol is associated with increased appetite, especially for sugar. In cases of enduring stress, this can stimulate food consumption to the point of overeating with all the detrimental consequences we are so familiar with. Moreover, too much cortisol can slow the metabolism, causing more weight gain than would normally occur. It can also affect fat distribution. Fat in the stomach area is considered a greater health risk than when it's stored around the hips and thighs.
Ultimately, we will not be able to address the obesity crisis effectively if we continue to ignore the effects of chronic stress on our hormonal system, says Dr. Peters. Asking people to diet and force themselves to lose weight through deprivation can only make things worse. The solution is to de-stress our lives. This doesn't mean more yoga and meditating, although that can help too, but mostly better socio-economic security and, as a result, peace of mind for more people.
As a point in case he cites a study conducted by the University of Chicago that compared two groups of single mothers from low-income neighborhoods. One group of women was moved to a more upscale area with safer streets, greater job opportunities and better schools, the other was left in place. Within a few years, most of the women who had moved away showed considerable improvement in their health, especially in reduction of diabetes and obesity. As their stress lessened, their well-being increased on every level.
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