Most doctors believe that obesity is the result of consuming more calories than a body burns. Recent research suggests that genetics and other factors may also play a role.
Rubin cautions that the study is preliminary and raises as many questions as it answers.
But the possibilities for human weight control are intriguing, and they may include developmental as well as metabolic factors.
"Just imagine a way to keep people from getting fat that is not [only] about how many Oreos they eat or how much they exercise—but about keeping them from forming fat cells in the first place," he said.
No Guilt-Free Solutions
But if the prospect of consequence-free overeating and sloth sounds too good to be true, it probably is, experts say.
"The reason we have those cells is to take [in] excess fat," said Roger Unger, an obesity researcher at the University of Texas Southwestern Medical Center.
"If you inhibit [fat cells] and overeat, you haven't done that person a favor," said Unger, who was not involved in the new research.
"The surplus lipids would end up in organs where you don't want to have surplus lipids—like the heart and the liver."
"People that don't have [as many] fat cells, if they overeat, get very sick—[they get] sicker at a much earlier age than people who first get fat and then develop complications."
Rexford Ahima is a University of Pennsylvania endocrinologist.
"The idea that 'non-strenuous work' can reduce body fat is intriguing; however, the findings have to be interpreted with caution," he said.
Ahima noted that key information regarding the mice's energy expenditure, hormones, and metabolism remains unknown and may have impacted the results.
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