I'm a board-certified cardiologist. Back then, if a trial hadn't shown it, it wasn't real. The one nutrition lecture I got in medical school ended with a line I still remember: "The only thing supplements do is give you expensive urine." Most of the medical students in the room believed him.

Then a colleague pointed me toward the anti-aging fellowship. The training changed how I thought. My group didn't care for my new perspective, though partners would quietly close my door and ask what they ought to do about their own suboptimal test results. When I proposed opening a preventive practice, one interventional cardiologist said, “If you prevent heart disease, we won't be able to put in stents.” I said, "If that's how you feel, then we should put a cigarette machine in the lobby.”

Trials tell you what works for a population. No one has ever been a population. Personalized precision medicine is the future, and it's here today if you look for it.