​Meet ​Our Team

Meet our premier age management specialist physicians team

Julie McCallen, M.D.

President of Cenegenics Denver

Dr. Julie McCallen is the President of Cenegenics Denver. She is board-certified in Family Medicine, a member of the Endocrine Society, the International Hormone Society, American Academy of Family Physicians, and the Age Management Medicine Group. After earning an undergraduate degree in Biochemistry from Cornell University, Dr. McCallen received her MD from the University of Pittsburgh School Of Medicine in 1990. She completed her residency in Family Medicine at the University of Wyoming-Casper in 1993.

Dr. Eipe Kuruvila

Center Physician

Dr. Kuruvila attended medical school at JIPMER, Pondicherry, one of the top medical schools in India. His graduate training was in the UK, including anesthesiology at The University of Bristol Hospitals followed by Higher Professional training at The Middlesex Hospital. He later attended Medical School in London for another four years. He and his family moved from London to Denver after they fell in love with skiing in the Alps. Dr. Kuruvila completed his fellowship in Anesthesiology and Pain Management at the University of Colorado Health Sciences Center in Denver.

Dr. David Cox

Center Physician

Dr. David Cox is a Board-Certified Urologist and a Fellow of the American College of Surgeons. He was a consultant to the Urology Service at Walter Reed Medical Center, Chief of Biochemistry at the Walter Reed Army Institute of Research, and a Guest Worker in the Surgery Branch at NIH. During his many years in the private practice of Urology, he treated all issues of the urinary tract and was particularly interested in treating sexual dysfunction issues in men. Always interested in fitness from his days as a college athlete, Dr. Cox continues to teach martial arts.

Tim Watt, M.D.

Center Physician

Tim J Watt, MD, FAANS, and FAAAAM is certified by the American Board of Neurological Surgery and The American Board of Anti-Aging Medicine. He has completed the Advanced Fellowship in Anti-Aging, Functional, and Regenerative Medicine of The American Academy of Anti-Aging Medicine. Dr. Watt is a co author of the written board exam in Anti-Aging Medicine and was a medical editor and contributing author to The Physicians Guide to Anti-Aging Medicine and The Encyclopedia of Clinical Anti-Aging Medicine. Dr. Watt attended Wichita State University and the University of Kansas School of Medicine.

Dr. Watt is currently doing The Fellowship in Age Management Medicine working at Cenegenics Denver. He still practices Neurosurgery full time in Rapid City, South Dakota, where he is part owner in a Surgical Specialty Hospital.

Jared Sparr

Certified Personal Trainer

Jared earned his BA in Adult Fitness and Exercise Science from Metro State University, with a minor in nutrition. As an NSCA-certified master level strength and conditioning specialist for the past eight years, Jared has a deep passion for helping people achieve their health and strength goals. He has trained many professional athletes, from skiers and football players to hockey and baseball players, along with many collegiate athletes.

Rod McCallen

Certified Personal Trainer

Rod is an ACSM certified personal trainer. As a master merchant seaman, Rod has always attended carefully to his level of fitness. He joined Dr. McCallen at Cenegenics in 2008 and has been instrumental in the growth and development of Cenegenics Denver.

Jackie Twigg

Patient Service Coordinator

Jackie is our Patient Service Coordinator at the Denver office. She assists with patient inquiries, maintains day-to-day operations at the office, schedules patient visits and consults, and processes prescription fulfillment and lab requisitions. Jackie’s mother is a nurse which sparked her interest in the medical field at young age. Her passion to help others is what inspired her to seek a job with Cenegenics Denver.

Lizz Lippert

Patient Service Coordinator

Lizz Lippert, our newest Patient Service Coordinator, has a B.S. in Cell and Molecular Biology from the University of South Florida and has been in the medical field for over 5 years in rehabilitation and long term care, intense and progressive care units, surgical units, and most recently labor and delivery. She is looking forward to bring her medical knowledge to us and excited about being on the front lines of optimal health and disease prevention. She believes that the best offense is a good defense, and is thrilled to be a part of our team.


Resources for You


Read our White Paper, Defy Your Age with Cenegenics, and learn about the science of age defiance and the Cenegenics process.

Official Youtube

Free advice from Cenegenics physicians, video testimonials from patients, and other news.


Read regular updates from Cenegenics on our blog.