Can mild vibrations make you thinner, with stronger bones? They apparently can if you're a mouse.

Clinton T. Rubin at the State University of New York at Stony Brook put mice on a vibrating platform for 15 minutes a day, five days a week, for 15 weeks and reported that the "buzzed" mice had 27 percent less fat and correspondingly more bone than mice who didn't undergo the treatment. The metabolic rates in the treated mice were no different from those in the control mice. There was also no difference in insulin or blood glucose levels.

However, these were not diabetic mice. (In fact, I'm always surprised that there are any diabetic mice left, considering how many times they've been cured of diabetes in research studies.) The treatment also reduced some risk factors for type 2 diabetes, including free fatty acids in the blood and triglyceride levels in the liver.

Why this increase in bone and decrease in fat occurs is not clear. A few years ago, scientists learned that some precursor cells (stem cells) in the body can produce either bone cells or fat cells, as well as muscle cells, depending on what kind of signals they get, and when the development of one type of cell is stimulated, the development of the other type is hindered.

This seems to be happening in people who take the glitazone drugs (Avandia and Actos). We know that the glitazones increase the differentiation of precursor cells into fat cells. These new, small fat cells are less insulin resistant than the old, large fat cells, and they take up more glucose, reducing the amount of glucose in the blood.

However, last spring it was reported that people taking the glitazone drugs were at greater risk of bone fractures, suggesting that the production of the new fat cells was at the expense of new bone cells.

Dr. Rubin's research was done not because he enjoys vibrating mice but because he was trying to figure out why we all lose bone density as we age. Because exercise jars the muscles, and because most people do get less exercise as they age, Rubin wondered if "artificial exercise" in the form of vibrations would do the trick. The vibrations he used on the mice were less than one would get by walking.

Rubin's article will be published in the Proceedings of the National Academy of Sciences and is available online here.

The idea of using vibrations or electric shocks for weight loss is not new. Way back in the 1950s, I can remember the fad of using something called the Relaxacisor, which was supposed to use small electric shocks to make your muscles work with no effort on your part. You wrapped the gizmo around the body part you wanted to reduce, plugged it in, and hoped you'd soon have thinner thighs or beautiful butts. Luckily, I was never able to afford the Relaxacisor, so I was spared its tortures.

Another device from the 1950s was called the Imperial Belt Massager Exercise Machine. You put the belt around your waist and let it vibrate your whole body, hoping it would vibrate your fat away. As I recall, when these devices were in vogue, there wasn't a sudden glut of formerly fat people, even though a lot of them tried these devices, which didn't seem to do much but help people get rid of their excess cash.