Dr. John Spencer Ellis compares metformin and berberine as longevity protocols: how they overlap, how they differ, what each is approved to treat versus what each is claimed to treat, and what the evidence actually supports. This 49-slide presentation covers the shared AMPK mechanism, the glycemic and lipid data behind both, the counter-evidence most longevity content omits, and a decision framework for men over 40. "Metformin or berberine for longevity? Dr. John Spencer Ellis compares mechanism, evidence, safety, and interactions — including what most content leaves out."