GRONINGEN, Netherlands, March 11 (UPI) -- Dutch scientists say they've used lab mice to determine the theory that a higher metabolism results in a shorter lifespan is unfounded.
Lobke Vaanholt of the University of Groningen, who led the study, said she and her colleagues discovered mice with increased metabolism live just as long as those with slower metabolic rates.
The live-fast, die-young premise, scientifically known as the rate-of-living theory, was first proposed in the 1920s, Vaanholt said. The hypothesis was that aging is the inevitable byproduct of energy expenditure and the faster the energy is expended, the faster aging occurs and the sooner death occurs.
Vaanholt and her team followed two groups of mice through their entire lives, with one group's environment kept at 71 degrees Fahrenheit and the other group at 50 degrees Fahrenheit. The colder group had to expend more energy to maintain body temperature and, if the rate-of-living theory was correct, should have died sooner.
"Despite a 48 percent increase in overall daily energy expenditure and a 64 percent increase in mass-specific energy expenditure throughout adult life, mice in the cold lived just as long on average as mice in warm temperatures," the researchers said.
The study appears in the journal Physiological and Biochemical Zoology.
