Ironically, what enables life to exist is what ultimately ends it: oxygen. This fascinating program analyzes the aging process, showing ways to build a longer-lasting human. The benefits and perils of hormones as an elixir of youth are discussed by Dr. Ron Livesey, who runs an anti-aging clinic in New York, and Professor Stephen Shalet, an expert on human growth hormone who explains its link to cancer. The attempt to retard aging by slowing metabolism is seen in a man on a special diet of less than 1500 calories a day. Molecular gerontologist Dr. Simon Melov and Dr. Gordon Lithgow, both of The Buck Institute for Age Research in California, discuss the most promising strategy—controlling rogue elements called free radicals, the by-products of metabolizing oxygen, with antioxidants. A BBC Production. (50 minutes)