the researchers in the next researchers fed one pair of mice a diet in these 60 percent of calories arrived from fat . the diet starts before the mice , all males , were 1 year younger , which is old - years in mammalian longevity . as expected , the population also develop signs of early diabetes , with grossly enlarged pancreas , and began to recover much sooner than mice supplied a standard nutrition .
At the age of one year, male mice were fed with a diet in which 60 percent of calories came from fat.