Harvard professor David Sinclair reveals breakthrough research showing human cells can be rejuvenated by 75% in 8 weeks, with first human trials launching this year to reverse blindness and potentially cure age-related diseases. His Information Theory of Aging explains why aging is a treatable disease, not inevitable decline, and he details proven lifestyle interventions—fasting, exercise, specific supplements—that can extend healthy lifespan by 10-20 years. Aging is caused by loss of epigenetic information (identity crisis in cells), not DNA damage itself, and can be reversed by reinstalling cellular 'backup copies' from youth through gene therapy. Fasting raises NAD levels, activating sirtuins that repair DNA and preserve cell identity; skipping meals combined with aerobic exercise are the highest-impact longevity interventions available today.