Meet Our Team

The providers and staff dedicated to helping you feel like yourself again

Medical Director · Board-Certified Emergency Physician

Dr. James O. Hill II, DO

Board-certified emergency physician and specialist in osteopathic medicine. Dr. Hill completed his specialty training at Jackson Memorial Hospital and Mount Sinai Hospital in Miami after graduating from Nova Southeastern University College of Osteopathic Medicine. He served the U.S. Army as an ER physician with the 86th Combat Support Hospital in Baghdad and as director of the Emergency Department at the 121st Combat Hospital in Seoul, South Korea. He later founded the North Star Treatment Center for Addiction, where firsthand experience with the harms of opioids and benzodiazepines shapes his commitment to safer, evidence-based alternatives for every Impact Health patient.

Co-Founder and CEO

Steven Martinez

Co-founder and CEO of Impact Health Clinics, Steven leads the vision and operations behind our growing clinic network across north Mississippi. He partnered with Melissa to build Impact Health around one principle: every patient deserves cutting-edge hormone optimization, medical weight loss, and wellness care delivered with the personalized attention big health systems rarely provide. His mission is to make optimal health accessible, combining proven clinical protocols with technology, education, and a team that treats patients like neighbors, not numbers.

Co-Founder & Clinical Director

Melissa Vinson, NP

Clinical Director and lead Nurse Practitioner at Impact Health, Melissa brings 22 years focused on obesity medicine and medical weight loss to every patient she treats. She oversees clinical care across all four locations, reviews patient protocols and complex cases, and personally guides many of our weight loss and hormone optimization patients through their journey. Her approach pairs evidence-based medicine with judgment-free, compassionate coaching, helping north Mississippi patients feel confident, supported, and energized as they take control of their health.

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Our Clinic Team

The faces you'll see, and the voices you'll hear, at every visit

Clinical Operations Coordinator

Alesha Harber

Alesha keeps the day-to-day at Impact Health running smoothly, coordinating schedules, patient follow-ups, and communication across our clinics. She is often the first friendly voice patients hear, and she makes sure every visit, refill, and follow-up happens right on time.

Book time with Alesha

Nurse Practitioner · Olive Branch

Keona Phillips, NP

Keona is the Nurse Practitioner at our Olive Branch clinic, providing hands-on care across hormone optimization, medical weight loss, and wellness programs. She builds each treatment plan around the patient in front of her, their labs, their goals, and their lifestyle, and stays with them through every follow-up.

Clinical Triage Nurse · Olive Branch

Amanda Roman

Amanda is the Clinical Triage Nurse at our Olive Branch clinic and the first clinical point of contact for patients, handling triage questions, labs, injections, and in-clinic support. She keeps patients informed and comfortable at every step of their treatment.

Ready to Meet Us in Person?

Book a consultation at any of our four clinics or via telehealth

Schedule Your Consultation

Call 877-665-6767