GCB's Avsholom Caspi and Terrie Moffitt and colleagues have identified multiple health factors that may be combined to determine whether people are aging faster or slower than their peers. Using data collected from the Dunedin Study, a longitudinal study that has followed more than 1,000 people in New Zealand from birth to the present, the authors found that study participants who were "biologically older" than their peers had exhibited signs of aging as indicated in tests such HDL cholesterol, cardiorespiratory fitness, telomere length, dental health, and other biomarkers. Moffitt, Caspi, and their collaborators hope to eventually refine these multi-factorial measurements of aging to identify areas in which medicine could slow the aging process and extend quality of life and activity levels in adults. Listen to first author Dan Belsky discussing the research on BBC Newshour, read about it in the Wall Street Journal, read the PNAS paper, or humorous coverage in The Onion.