Last Thursday, scientists at Columbia University published a new study finding that cutting down on calories could lead to longer lives. In the phase 2 trial, 220 healthy people without obesity dropped their calories significantly, and a test of their biological age showed that their rate of aging slowed by 2 to 3 percent in over a couple of years. Small though that may seem, it amounts to a decline of about 10 percent in the risk of death as people get older, according to the researchers' estimate. That's basically the same as quitting smoking.Previous research has shown that restricting calories results in longer lives for mice, worms and flies. This research is unique because it applies those findings to people. It was published in Nature Aging.But what did the researchers actually show? Does the new paper point to anything people should be doing to have longer, healthier lives? Spoiler alert: Maybe, but first, you'd want to consult a medical expert about it. I had the chance to chat with someone with inside knowledge of the research -- Dr. Evan Hadley, director of the National Institute of Aging's Division of Geriatrics and Clinical Gerontology, which funded the study. Dr. Hadley describes how the research participants went about reducing their calories, as well as the risks and benefits involved. He also explains the "aging clocks" used to measure the benefits.Leaps.org is a not-for-profit initiative that publishes award-winning journalism, popularizes scientific progress on social media, and hosts events about bioethics and the future of humanity. Visit the platform at www.leaps.org. Podcast host Matt Fuchs is editor-in-chief of Leaps.org.