BLI Staff



Dr. Elizabeth Yurth is the Co-Founder and Medical Director of Boulder Longevity Institute, where she has been providing Tomorrow’s Medicine Today to her clients since 2006.  Dr. Yurth obtained her Medical Degree from the University of Southern California Keck School of Medicine and completed her residency at the University of California – Irvine. Along with her 25-plus years as a practicing orthopedist specializing in sports, spine, and regenerative medicine, Dr. Yurth is double-Board Certified in Physical Medicine & Rehabilitation and Anti-Aging/Regenerative Medicine. She has a Stanford-affiliated Fellowship in Sports and Spine Medicine, and a dual-Fellowship in Anti-Aging and Regenerative Medicine (FAARM) and Anti-Aging, Regenerative and Functional Medicine (FAARFM) through the American Academy of Anti-Aging Medicine (A4M). Dr. Yurth has also completed a Fellowship in Human Potential and Epigenetic Medicine, is part of the first cohort of providers to receive the A4M National Peptide Certification, and is a faculty member and national lecturer for both A4M and the International Peptide Society(IPS).  She is a member of IPS’s very first Peptide Mastermind Group, comprised of a small elite group of national peptide experts.

Dr. Yurth has completed over 500 hours of Continuing Medical Education (CME) training in the areas of Longevity, Epigenetics, Nutrition, Bioidentical Hormone Replacement Therapy, Regenerative Peptide Treatments, and Regenerative Orthopedic Procedures. As an athlete herself who has dealt with numerous injuries, Dr. Yurth is thrilled to share with her clients all the innovative, life-changing treatments that are on the cutting-edge of medicine.  

Tammy Cayou, MSN, CPNP, ABAAHP

Tammy Cayou comes to Boulder Longevity Institute after a long career in pediatrics. She worked at Children’s Hospital in Denver in critical care and cardiology, and was a nurse practitioner at a large pediatric practice in Leesburg, Virginia where her focus was on breastfeeding, parenting, nutrition and the health of the entire family.  After receiving her Master’s and Nurse Practitioner Certification, she worked as an NP with the Department of Pediatric Neurosurgery at the University of Colorado. Tammy has obtained her prestigious fellowship in Metabolic and Functional Medicine, as well as a Brain Fitness Certification.

Tammy met Dr. Yurth in 2015 while undergoing treatment for an arthritic hip and a subsequent hip replacement. Realizing that Boulder Longevity Institute’s ideals and goals for maximizing human potential and the prevention of disease matched her interests and career goals, Tammy joined BLI in March of 2015.  She is excited to help people prevent disease instead of treating disease.

Brian Graham, CPS, ACSM-CPT

Brian Graham is one of the leading Peptide Specialists in the nation, and also serves as a Regenerative Therapy Consultant for Boulder Longevity Institute.  He is part of the first cohort of providers to receive the A4M National Peptide Certification, and is a member of the International Peptide Society’s very first Peptide Mastermind Group, which is comprised of a small elite group of national peptide experts.  As a Certified Peptide Specialist with a Certified Personal Trainer certification from the American College of Sports Medicine, Brian joined Dr. Yurth at BLI in 2019 to run the Nation’s first Medically Managed Peptide Program. 

After graduating from the University of Colorado in Boulder with a degree in Integrative Physiology, Brian worked in the healthcare industry taking care of patients in the areas of orthopedics, dermatology,  physical therapy, and home health care.  Brian combines his athletic background as a collegiate soccer player, coach, Navy SEAL candidate, and personal trainer with his passion to support his patients throughout their journey to optimized health.

Cheryl O’Connor, BSN, Clinical Operations Manager

Cheryl O’Connor comes to BLI with both a medical and operations background. Having grown up in Vermont as a high performance Junior Olympic Alpine skiier for Stratton Mountain School and the US Developmental Team, she understands the realm of human optimization. Cheryl has extensive experience in clinical operations and clinical trials as a senior project manager and clinical operations lead, and has excelled as a nurse in clinics specializing in Cardiology, Oncology, Allergy and Asthma, and Head and Neck Surgeries.

Cheryl received her Bachelor of Science in Nursing degree in Colorado. Her knowledge base from her clinical, operational and personal athletic ventures are integral and in line with BLI’s philosophy to provide clients with the most cutting edge, medically-managed treatment options available.

David Van Bussum, CEO and Co-Founder

David W. Van Bussum is the Co-Founder and CEO of Boulder Longevity Institute, providing business, marketing, and financial guidance to the enterprise.  As an entrepreneur with an extensive background in technology and marketing, Mr. Van Bussum has founded or co-founded over half a dozen companies in the last fifteen years with a significant emphasis in the healthcare and healthcare technology areas.

Prior to joining BLI, Mr. Van Bussum co-founded and served as the CEO and Chairman of NetMedical Corporation, a healthcare-specific telecommunications utility, co-founded and served as President of MetriXPro, Inc. an internet-based financial services company, was a principal in, and served as Vice President of Business Development for, Anamatix, Inc, a web-based clinical care company focused on musculoskeletal rehabilitation, and was the President and Chairman of Sanitas Valley Partners, Inc., a retail venture he founded with interests in the outdoor industry.

Before embarking on his entrepreneurial path, Mr. Van Bussum held Director of Sales, Director of Marketing, International Business Development, and IT Management positions with Fortune 500 Companies in the Aerospace and Telecommunications industries including McDonnell-Douglas (now Boeing), Bay Networks, and Nortel Networks. 

Mr. Van Bussum has a Distributed Studies Computer Science Degree from the University of Colorado in Boulder and a certification in Advanced Telecommunications Management from the USC Marshall School of Business.