In this age of lunchtime lifts, wrinkle-erasing injections, furrow fillers, and lip plumpers, there's no question that anyone who aims to look younger easily can. But Lauren Kessler wants something more than to follow the cosmetic path to youthfulness. She wants to live with energy, stamina, vitality, resilience, and health for a very, very long time. Her goal: to reverse her biological age from the inside out. Guided by both intense curiosity...