The experiments show aging is a reversible process, capable of being driven "forwards and backwards at will," said anti-aging expert David Sinclair, a professor of genetics in the Blavatnik Institute at Harvard Medical School and codirector of the Paul F. Glenn Center for Biology of Aging Research. Our bodies hold a backup copy of our youth that can be triggered to regenerate, said Sinclair, the senior author of a new paper showcasing the work of his lab and international scientists. The combined experiments, published for the first time Thursday in the journal Cell, challenge the scientific belief aging is the result of genetic mutations that undermine our DNA, creating a junkyard of damaged cellular tissue that can lead to deterioration, disease and death.