Mon\u2013Sat: 7:00 AM \u2013 8:00 PM  142 Serenity Blvd, Greenfield, CA

Our Leadership Team

Meet the visionary physicians, specialists, and advisors who have dedicated their lives to advancing integrative wellness.

Dr. Margaret Chen
Founder & Chief Executive

Dr. Margaret Chen

MD, PhD \u2014 Founder & CEO

Dr. Margaret Chen is a Harvard Medical School graduate with a dual specialization in Internal Medicine and Integrative Health Sciences. After completing her residency at Johns Hopkins and a fellowship at the Mayo Clinic, she pursued advanced studies in Traditional Chinese Medicine in Beijing, Ayurvedic medicine in Pune, India, and functional medicine in Zurich, Switzerland.

With over 28 years of clinical experience, Dr. Chen has authored four books on integrative medicine, published 47 peer-reviewed research papers, and been featured on CNN Health, NPR's Morning Edition, and The Today Show. She serves on the board of the American Integrative Medical Association and is a frequent keynote speaker at global health conferences.

Her greatest pride, however, is the 20,000+ patients who have regained their vitality under VivaWell's care. "Medicine should serve the whole person," she says. "That belief is the foundation of everything we do."

CREDENTIALS & AFFILIATIONS

MD \u2014 Harvard Medical School PhD \u2014 Integrative Health Sciences Fellow \u2014 Mayo Clinic Certified \u2014 Functional Medicine (IFM) TCM \u2014 Beijing University AIMA Board Member

Senior Leadership

Our C-suite and department heads bring decades of combined expertise across medicine, wellness, and healthcare management.

Dr. James Okafor

Dr. James Okafor

Chief Medical Officer

Board-certified internist with 22 years of experience in functional and preventive medicine. Former Chief Resident at UCSF Medical Center.

Dr. Priya Sharma

Dr. Priya Sharma

Director of Naturopathic Medicine

Licensed naturopathic physician specializing in hormonal balance, autoimmune conditions, and gut-brain axis therapies. Harvard-trained researcher.

Mr. David Park

Mr. David Park

Chief Operations Officer

Healthcare operations executive with an MBA from Stanford and 18 years scaling integrative health platforms across the US and Canada.

Ms. Sarah Whitfield

Ms. Sarah Whitfield

Chief Wellness Officer

Certified wellness coach, mindfulness teacher, and organizational psychologist specializing in corporate wellness and resilience programs.

Dr. Carlos Rivera

Dr. Carlos Rivera

Head of Physical Rehabilitation

Sports medicine physician and physical therapist with specialization in injury recovery, orthopedic rehabilitation, and athletic performance.

Dr. Aisha Nwosu

Dr. Aisha Nwosu

Director of Nutrition Sciences

Registered dietitian and PhD nutritional biochemist. Pioneered VivaWell's signature metabolic reset program with a 94% patient success rate.

Expert Practitioners Across Every Discipline

Dr. Lin Wei

Dr. Lin Wei

Senior Acupuncturist

TCM Pain Management

Licensed acupuncturist with 15 years of clinical experience treating chronic pain and neurological conditions.

Ms. Rachel Torres

Ms. Rachel Torres

Head Massage Therapist

Deep Tissue Lymphatic

Certified massage therapist and myofascial release specialist with a decade of therapeutic practice.

Mr. Alex Kim

Mr. Alex Kim

Yoga & Mindfulness Lead

Hatha Meditation

E-RYT 500 certified yoga teacher and mindfulness-based stress reduction (MBSR) instructor.

Dr. Lisa Nguyen

Dr. Lisa Nguyen

Chiropractor

Spinal Care Posture

Doctor of Chiropractic specializing in spinal alignment, posture correction, and nerve function restoration.

Mr. Tom Bailey

Mr. Tom Bailey

Physical Therapist

Rehab Sports

Licensed PT specializing in post-surgical recovery, sports injury rehabilitation, and functional movement.

Dr. Fatima Hassan

Dr. Fatima Hassan

Herbal Medicine Specialist

Herbalism Ayurveda

PhD in Ethnobotany with expertise in Western herbal medicine and Ayurvedic botanical formulations.

Ms. Jennifer Moss

Ms. Jennifer Moss

Clinical Psychologist

CBT Trauma

Licensed clinical psychologist offering cognitive behavioral therapy, trauma-informed care, and stress management.

Mr. Brian Osei

Mr. Brian Osei

Fitness & Rehab Coach

Strength Mobility

NSCA-certified strength coach and corrective exercise specialist with 12 years training clients of all fitness levels.

Advisory Board

Distinguished experts who advise VivaWell on research, ethics, and the future of integrative medicine.

Prof. Robert Nash

Prof. Robert Nash

Harvard School of Public Health

Professor of Epidemiology and Health Policy. 30+ years studying lifestyle medicine and chronic disease prevention across 14 countries.

Dr. Yuki Tanaka

Dr. Yuki Tanaka

WHO Integrative Health Advisor

Senior consultant to the World Health Organization on traditional and complementary medicine policy in Asia-Pacific regions.

Mr. Samuel Grant

Mr. Samuel Grant

Healthcare Innovation Executive

Former SVP at Kaiser Permanente with expertise in digital health strategy, patient experience design, and healthcare technology integration.

Dr. Angela Diaz

Dr. Angela Diaz

Nutrition Research Scientist

Lead researcher at the NIH National Institute of Nutrition. Authored over 60 studies on the microbiome, metabolic health, and functional foods.

Awards & Achievements

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Top 10 Wellness Centers

Health & Vitality Magazine \u2014 2022, 2023, 2024

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5-Star Patient Rating

Healthgrades & Google Reviews \u2014 4.9/5 average across 3,800+ reviews

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Best Integrative Practice

California Medical Association \u2014 Best Integrative Practice 2023

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Community Impact Award

Greenfield City Council \u2014 Excellence in Community Health 2024

Care Delivered By People Who Truly Care

Our team of 45+ specialists is ready to create a personalized wellness plan just for you. Start your journey today.

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