You only have one life. Make the most of it.


Dr. Chris Renna

Dr. Renna graduated from University of Texas, earned his medical degree cum laude from the University of North Texas Health Science Center and completed a residency in family medicine. In his initial years of practice, he learned that medical school prepared doctors to diagnose disease but did not prepare them to create health.

Dr. Renna decided to truly help his clients improve health, he needed to create an entirely new system and approach.  This was the beginning of LifeSpan medicine.  LifeSpan provides comprehensive and focused medical evaluations specializing in preventing disease, resolving symptoms and improving health.  These programs are delivered through personalized concierge support, access to your medical team 24/7 and exceptional follow up. 

Since founding LifeSpan medicine in 1992, Dr. Renna has maintained a small practice focused on optimal health with two rules. 

Everything is about you.
Everything is about your health.

Over the years his passion and dedication to clients as well as his unique approach has earned him an exceptional reputation as the nation’s premiere preventive medicine provider. He is a published author, popular public speaker and lecturer to audiences across the United States and abroad.

“Dr. Renna changed my life. All of the injuries from my athletic youth were starting to add up and the constant pain from arthritis seemed to be something I was going to have to live with. Since having the injections I have been able to ski..and to live my active life without having to manage pain.”


Janine Blackman, MD

Dr. Blackman graduated from University of Maryland School of Medicine’s combined MD-PhD program. Her PhD in Epidemiology & Preventive Medicine included research in the benefits and risks of hormone therapy for women. She completed residency in Family Medicine in Baltimore and a fellowship in Integrative Medicine at University of Maryland. She subsequently served as Medical Director of the Integrative Medicine Center at University of Maryland prior to working in private integrative medicine in the greater Washington, DC area from 2006-2018. She moved to California to join LifeSpan medicine in 2018.

Dr. Blackman brings almost two decades experience in applying integrative and functional medicine approaches for optimizing health and disease prevention, including bio-identical, custom-compounded hormones for women and men. She trained in the Bredesen Protocol for prevention and treatment of Alzheimer’s Disease through the Institute of Functional Medicine in 2017. She is also the invited author of Hormones in Women at Mid-Life & Beyond, published in Integrative Sexual Health, New York: Oxford University Press, Weil Integrative Library, March 2018.

Finding herself surrounded by pharmaceutically-minded faculty during medical school, she pursued training in Preventive Medicine and Complementary and Alternative Medical Therapies to learn how to optimize the conditions to support the body’s innate ability to heal itself. From simple signs of imbalance, such as elevated blood pressure or the inability to get a good night’s rest, to the many complex conditions, such as auto-immune disease, persistent fatigue and pain syndromes, metabolic diseases and cancer, Dr. Blackman takes the time to learn about each individual client and works to find unique and personalized solutions for health issues as well as identify and support the treatments and lifestyle changes most likely to encourage healing and thriving throughout life.


Dr. Moshe Ben-Roohi

Moshe Ben-Roohi, M.D. specializes in advanced non-surgical orthopedics and regenerative treatments for sports injuries, degenerative joint disease, and conditions of the spine. He often works with clients who have tried everything else and failed. 

He is double board certified in Physical Medicine and Rehabilitation (PM&R) and Pain Medicine. He obtained his medical degree at Tel-Aviv University’s Sackler School of Medicine and residency at NYU Medical Center and Hospital for Joint Diseases where he served as Chief Resident. After residency he completed a fellowship in Interventional Spine and Sports Medicine. 

Dr. Ben-Roohi maintains his role in academic medicine through his continued pursuit of ongoing research. He has published numerous scientific papers in PM&R and other peer reviewed journals. He is a frequent speaker on the subjects of Sports Medicine, Pain Management and Molecular Orthopedics. Dr. Ben-Roohi is a member of the American Medical Society for Sports Medicine (AMSSM), North American Spine Society (NASS), International Spine Intervention Society (ISIS), International Cellular Medicine Society (ICMS), American Academy of Orthopedic Medicine (AAOM), Institute for Functional Medicine (IFM) and the American Academy of Physical Medicine and Rehabilitation (AAPMR).

Dr. Jared Greenberg

Dr. Jared Greenberg is a leading specialist in regenerative and non-surgical orthopedics and recognized by his peers as a top doctor in spine medicine. Dr. Greenberg is board-certified in PM&R, and a fellow of the American Academy of Physical Medicine and Rehabilitation. He has performed over 12,000 spine, joint and bursa injection procedures in his career and has an expertise utilizing top technologies including fluoroscopic X-ray or ultrasound guidance for added accuracy and precision.

Dr. Greenberg attended the University of Pennsylvania in Philadelphia, PA for medical school. After completing his M.D. degree, he began an Orthopedic Surgery residency at the University of Wisconsin in Madison, WI. During his surgical training, Dr. Greenberg realized that he was more interested in non-operative treatments of musculoskeletal conditions, rather than operative. In 2006, Dr. Greenberg then returned to Philadelphia for a second residency, in Physical Medicine and Rehabilitation (PM&R). He completed this program at the Hospital of the University of Pennsylvania in 2009, and served as a Chief Resident for two consecutive years.

Dr. Greenberg then received subspecialty training as an Interventional Spine Fellow / Clinical Lecturer in the PM&R Spine Program at the University of Michigan Health System in Ann Arbor, MI. Dr. Greenberg was also selected to serve as a National Board Examiner through the American Board of Physical Medicine and Rehabilitation.


Dr. Mary Caire

Dr. Caire graduated from LSU medical school, New Orleans in 1997.   In 2002, she completed a 5-year double residency in the Physical Medicine and Rehabilitation (PM&R) and Internal medicine program, serving as chief resident her final year. She is board certified in PM&R.  She later completed a fellowship in Metabolic Medicine and Anti-aging and Regenerative Medicine and is board certified through the Metabolic Medical Institute at George Washington University School of Medicine and the American Academy of Anti-Aging and Regenerative medicine. 

Dr. Caire also served as President of Wise County Medical Society and is on the Texas State Medical Board Political Action Committee.

Her roots in traditional allopathic medicine provide a strong foundation for the integration of her functional medicine expertise. Dr. Caire believes in a functional approach to preserving health and preventing and treating chronic illness. By focusing on advanced testing, nutrition, exercise, stress management, DNA-informed precision medicine, digestive health, and hormonal balancing, she creates individualized comprehensive preventive plans for each individual to support health, function and prevent aging.  She guides clients in changing the course of short and long-term health for the better by understanding our unique DNA, the science of epigenetics and actively managing detailed aspect of health. 

Dr. Caire provides Comprehensive Executive health programs as well as Regenerative Sports medicine treatments for joint and back issues for all LifeSpan clients.

She is a published author and has lectured locally and nationally on topics related to precision medicine, addiction recovery, pain management, the use of big data in medicine, DNA-informed medicine and the future of medicine. Recent appearances include TEDx Turtle Creek, and Hope For Tomorrow on Texas47 TV.

Dr. Gina Nick

Dr. Nick is a renowned doctor who has been in private practice for 10 years in Newport Beach, CA where she provided concierge, functional, preventive medicine programs to executives in the Newport Beach community and throughout California. She is a California native who completed her undergraduate degree at UCLA and medical school in Tempe, Arizona. 

Dr. Nick specializes in functional, preventive medicine with a focus on executive health including nutrition, microbiome, hormone replacement, brain optimization, immune function and overall health.  Her practice focuses on truly understanding her clients and helping them prevent functional decline and improve health.

She is known for unparalleled dedication to her clients and their health. Her programs and care focus on identifying the principal cause of health issues and use leading edge treatments and customized recommendations to resolve these issues.

Dr. Nick is a published practitioner, an RMD and recognized speaker for ACAM and other medical organizations.  She has published numerous articles on primary care issue, preventive medicine, hormone replacement, detoxification and nutrition. She holds a seat on the board of directors at Angel Light Academy, a Youth Leadership Organization as well as the California Naturopathic Doctors Association. Dr. Nick was also awarded the Emord & Associates Excellence in Integrative Medicine Award for 2013-2014.

“I really do believe that the anti-inflammatory program at Lifespan Medicine changed our lives for the better and I can’t thank you enough as I know that the changes I made helped me with this pregnancy. The lifestyle changes have also given our little girl the best start she could hope for in life!”


Rachel Swanson, MS, RD

Rachel Swanson is a leading nutritionist at LifeSpan medicine specializing in individualized nutrition programs focused on optimum health, detoxification, weight loss, performance and peak physical function. She holds a masters in nutrition as well as a registered dietetic degree from NYU. Rachel began her accomplished career with the New England Patriots providing team nutrition programs focused on optimization of player health and team performance. She launched her private practice in nutrition consulting for different organizations and projects at Harvard, several nutraceutical companies and private physicians.

Rachel has worked with a broad range of individuals from celebrities, professional athletes to business professionals and moms, dads and families of all ages.  Her experience in dietetics and private practice have provided experience and expertise in a wide range of health issues and nutritional program to optimize health and prevention or manage disease such as cardiovascular disease, diabetes, weight loss/gain, anti-inflammatory diets, gastrointestinal health, chronic disease prevention, skincare/anti-aging, and sports nutrition. 

She is passionate about her work and 100% committed to helping each and every client succeed. Her current practice focuses on nutrition counseling, customized programs and nutritional education.Rachel is a renowned speaker and contributor to media and events like TechCrunch, FounderMade, Huffington Post, Dr Oz and more. Rachel holds memberships in multiple professional organizations such as California Academy of Nutrition and Dietetics, Dietician in Integrative and Functional Medicine, and American College of Sports Medicine.