New Study Proves Physiological Link Between Stress and Obesity

Stress and obesity are linked. Millions of American suspect this, research has already confirmed it, and now science may be down the path to reduce its prevalence. A study released July 1 in the journal Nature Medicine indicates a Georgetown University Medical Center team of researchers have discovered a mechanism by which stress activates weight gain in mice, and a method to turn it off.

Researchers subjected mice to a combination of high stress and a high calorie diet for two weeks, and compared weight gain to a control group of mice just eating a high calorie diet. Only the mice exposed to both high stress and high calories demonstrated significant weight gain, particularly around the mid-section.

Of mice and men

The study's senior author, Zofia Zukowska, M.D., Ph.D., from Georgetown University is currently making the rounds at a spate of talk shows and news outlets to explain the significance of the research. According to Zukowska on NPR's Diane Rehm Show, science is close to determining how to reverse the natural mechanism that mammals use to grow fat.

The stressed mice developed high levels of a neurotransmitter called neuropeptide Y and the receptor neuropeptide Y2, which induces the growth of fat cells. Once the researchers traced the pathway between transmitter and receptor, they began to manipulate it and block signals can lead to fat accumulation, thus reducing weight gain.

Future gains (and losses)

As a part of this research, the team found a substance that counters the growth of the neuropeptide Y and can stimulate the pathway to strategically create new deposits. Though the research is new, it may explain why people who are chronically stressed gain more weight than those who are not, and it has early potential for removing or reallocating fat.

Clearly this news has a high level of interest to the millions of people who watch the numbers on the scale creep steadily upward in times of stress. Previous studies have found that chronic stress induces either increased foodintake and body weight gain or decreased intake and body weightloss, and that it is most likely a physiological response. This study increases the realm of knowledge about why certain people gain weight, and what can possibly be done about it.

These mechanisms, determined inmice, may explain some of the epidemic of obesity occurringin our society. As such, the research team is in the process of seeking patents to begin studies in humans to eventually develop new drugs to combat stress-related obesity.

Regardless, the research does not provide carte blanche to indulge in "comfort food" in times of stress. While the findings suggest a definitive link between obesity and stress, and that science soon may be able to mediate the degree of weight gain, it does not reduce the health risks associated with stress and weight gain.

Sources:

Nature Medicine, Vol. 13, July 1, 2007, p. 803 - 811

Physorg.com

NPR, The Diane Rehm Show, Stress & Obesity July 9, 2007