Exercise takes energy, and presumably that is what combats obesity, but provocative experiments now suggest that jiggling might be enough. For 15 minutes almost every day for 15 weeks, scientists at Stony Brook University had mice sit on a buzzing platform that almost imperceptibly vibrated at 90 times per second, accelerating up and down at 20 percent the strength of the earth's gravitational pull. After this treatment, the mice had 27 percent less fat in their torso than mice kept on stationary platforms. They also had significantly reduced levels of fatty compounds linked with type 2 diabetes.

The researchers speculate that the vibrations inhibited the formation of fat cells from stem cells. The work could lead to a nonstrenuous, drug-free method for control of obesity, but the investigators caution that exercise remains key to weight control and loss. The results appear in the November 6 Proceedings of the National Academy of Sciences USA.