The Stress of Cold Temperatures Extends Lifespans

In 1986, John Holloszy of Washington University immersed his lab rats in shallow, cool water for four hours each day. They burned so many extra calories that they ate half again as much as control rats, but weighed less. The cold rats lived 10% longer, on average. Holloszy framed his report on this experiment not as a hormetic effect of cold exposure, but as a refutation of the “rate of living” hypothesis. In 2006, Gordon Lithgow of the Buck Institute for Aging Research exposed lab worms...