In the other study, an international team of researchers sought to understand more about a genetic variation that appears to help make thin people slim and fat people obese.
About 12 percent of people have the genetic variation. According to the researchers, a study of mice suggests that people who have the variation are generally skinner than others, but their bodies can go haywire -- and pack on more pounds than they should if they eat a high-fat diet.
The researchers suggested that genetic tests might help determine if people have the variation and, if so, reveal whether they should be concerned about a high-fat diet.
"If one could tell these carriers about the importance of adhering to a healthy lifestyle, the impact would be very significant, and even prolong their lifespan," said study co-author Dr. Johan Auwerx, a professor at the Ecole Polytechnique Federale de Lausanne in Switzerland.
The next step is to try a similar study with people, Auwerx said.
For more on obesity, visit The Obesity Society.
SOURCES: Umut Ozcan, M.D., assistant professor, Children's Hospital Boston and Harvard Medical School; Johan Auwerx, M.D., Ph.D., professor, Ecole Polytechnique Federale de Lausanne, Switzerland; Jan. 7, 2009, Cell Metabolism
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