WASHINGTON - The chubby black mice ate the equivalent of a junk food diet. They should have gotten sick.
They should have had blood sugar levels that were off the chart.
They should have been falling off their exercise rods. They should have died early.
But they didn't.
Most of those mice still are alive, spinning away on their exercise rods like skilled log rollers.
Their ample insides look like normal healthy mice, just super-sized.
How'd they do it? Huge amounts of red wine extract, that good-for-you standby.
It's too early to know if such a miracle pill could work for people, but scientists are excited. Some called the findings "spectacular."
"You have to pinch yourself to make sure that this is all real, but the study involved 27 different researchers, each of whom had a Eureka moment," said Dr. David Sinclair, the lead researcher of the mouse study published online today in the journal Nature.
The study by Harvard Medical School and the National Institute on Aging shows that heavy doses of the red wine ingredient resveratrol lowers the rate of diabetes, liver problems and other fat-related ill effects in obese mice.
Fat-related deaths dropped 31 percent for obese mice on the supplement, compared with fat mice that got no treatment.
The mice that got the wine extract also lived longer than expected, the study showed.
Other preliminary work still under way shows the wine ingredient has promise in extending the lives of normal-size mice, too, said Sinclair, a pathology professor with Harvard Medical School.
He has a financial stake in the research. He is co-founder of a pharmaceutical firm, Sirtris Pharmaceuticals Inc. of Cambridge, Mass., which is testing to see whether the extract can safely be used to treat people with diabetes.
For years, red wine has been linked to numerous health benefits. But the new study shows that mammals given ultrahigh doses of resveratrol can get the good effects of cutting calories without actually doing it.
"If we're right about this, it would mean you could have the benefit of restricting calories without having to feel hungry," Sinclair said. "It's the Holy Grail of aging research."
Even though he called the work "tantalizing," Dr. Howard Eisenson, director of the Duke University Diet and Fitness Center urged people not to get too excited.
"All of us who practice medicine have learned that we can't leap from studies in the lab - particularly in lab animals - to what will happen in humans," he said.
Resveratrol, produced when plants are under stress, is found in the skin of grapes and in other plants, including peanuts and some berries.