Leonard Guarente was 38 and previously a tenured professor at Massachusetts Institute of Technology when he decided to devote himself to one of the most alluring issues in biology: ways to slow down growing old. More than three a long time later, the seventy two-year-old Guarente is considered a grandfather https://www.wsj.com/health/wellness/longevity-antiaging-leonard-guarente-business-f55643f4?mod=health_lead_story