Meet the Founder
Dr. Stuart Weiss, MD
FACEP • FAAP • CBCP • Board-Certified Emergency Medicine & Pediatrics
41+ Years Protecting Lives
Dr. Stuart Weiss has dedicated over four decades of his career to emergency medicine and pediatrics. As a board-certified physician with dual fellowship status — Fellow of the American College of Emergency Physicians (FACEP) and Fellow of the American Academy of Pediatrics (FAAP) — Dr. Weiss has spent his life at the intersection of acute care, prevention, and innovation.
Perhaps most notably, Dr. Weiss served as Medical Director for the TCS New York City Marathon — the largest marathon in the world — where he was responsible for the medical safety of over 50,000 runners and millions of spectators. His expertise extends across major athletic events including the NYC Triathlon, NYC Half Marathon, Brooklyn Half Marathon, Tough Mudder, and the Ironman National Championships.
Global Health Leadership
Beyond the finish line, Dr. Weiss founded two organizations at the forefront of healthcare preparedness: iCrowd (Intelligent Crowd Solutions), specializing in mass-gathering medicine and business continuity planning, and MedPrep Consulting Group, providing disaster and pandemic preparedness consulting worldwide, including work as a USAID subcontractor on the PREPARE Project.
His career has equipped him with a systems-level understanding of human health — from the cellular to the population level — and a relentless drive to explore how nature's own mechanisms can support our well-being.
The Belief Behind TENACEA
Dr. Weiss's journey to founding TENACEA begins with a fundamental belief: your body already possesses extraordinary cellular defense systems. After 41 years in medicine, he has seen firsthand how powerful the human immune system truly is — and how, in our most challenging moments, it sometimes needs support.
Having watched family members and close friends face serious health challenges, Dr. Weiss became driven by a question: what if we could give the body's own defense systems every possible advantage? Not as a replacement for conventional care, but as a complement to it — providing the immune system with the natural support it needs to function at its very best.
That question led him to a remarkable discovery: some of the largest, longest-lived animals on Earth maintain extraordinary cellular integrity despite having trillions more cells than humans. Elephants, naked mole rats, bowhead whales — evolution has given these species enhanced versions of the same defense pathways that exist in your body. The science of Peto's Paradox pointed to natural compounds that support these very pathways.
TENACEA was born from this insight: we don't need to invent new defenses — we need to support the ones we already have. Every product is formulated to work alongside your healthcare provider's guidance, giving your body's innate immune intelligence the reinforcement it deserves.
41+
Years of Clinical Practice
50,000+
Athletes Protected as Marathon Medical Director
FACEP
Fellow, American College of Emergency Physicians
FAAP
Fellow, American Academy of Pediatrics
CBCP
Certified Business Continuity Professional
Global
USAID PREPARE Project Consultant
Our Mission
Reinforce the Defenses You Already Have
Your body's immune system is extraordinary — but it doesn't have to work alone. TENACEA exists to provide physician-formulated, nature-inspired support for your built-in cellular defenses. We believe in working alongside conventional care, not apart from it — giving your body every advantage.
Our Vision
A World Where Every Body Has Its Best Defense
We envision a future where no one faces their health challenges without every tool available. Through rigorous science, compassionate care, and unwavering quality, TENACEA aims to become the most trusted name in immune and cellular support — a partner in your wellness journey, alongside your healthcare team.
Explore What Nature Has to Offer
Discover the published research behind TENACEA's nature-inspired approach to cellular health and immune support.