Are you a rapid ager? Biological age is a better health indicator than the number of years you've lived, but it's tricky to measure
- Written by Aditi Gurkar, Assistant Professor of Geriatric Medicine, University of Pittsburgh

Do you ever wake up some days and think, “When I was younger, I could survive on just four hours of sleep, but now it seems like I need 10”? Or have you ever walked out of the gym and “felt” your...