Dr. Leah Tonkin, MD, MBA, DipABLM, is board certified in both Obstetrics & Gynecology and Lifestyle Medicine, bringing over 16 years of private practice experience in Memphis, Tennessee. On March 4, 2024, Dr. Tonkin joined Lifesigns—The Wellness Division of West Cancer Center— and was appointed Executive Director in 2025.
Prior to her current role, Dr. Tonkin served as a hospitalist with Integrated Physician Services, providing emergent care in labor and delivery as well as gynecologic surgery. She was also a partner in a private OBGYN practice. Dr. Tonkin earned her medical degree and completed her internship and residency in Obstetrics & Gynecology at the University of Tennessee Health Science Center.
A dedicated fitness enthusiast and advocate for holistic health, Dr. Tonkin became board certified in Lifestyle Medicine to guide patients through the six pillars of health: Nutrition, Physical Activity, Stress Management, Restorative Sleep, Social Connection, and Avoidance of Risky Substances.
Dr. Anita Arnold is the Medical Director at Lifesigns in January 2024. She is committed to the health and wellness of all her patients
After acquiring her BS at Baptist Memorial Hospital-School of Medical Technology, Dr. Arnold earned her medical degree from the University of Tennessee followed by residency and fellowship in Internal Medicine. She was awarded Baptist Memorial Hospital “Physician Quality Champion and was in the UT “Top Twenty Internal Medicine Teachers”
Dr. Felix Caldwell: Dr. Caldwell is a native Memphian and graduated Cum Laude from Vanderbilt University. He received his medical degree from The University of Tennessee Health Science, Chattanooga. Dr. Caldwell is Board Certified in Internal Medicine and is a fellow in the American College of Physicians. Following medical school, he served as Lt. Commander in the United States Naval Reserve with an Honorable Discharge. He enjoys gardening, hiking, going to movies, taking care of his three dogs and aquarium. Dr. Caldwell has practiced medicine for almost 40 years and has worked for Lifesigns since 2006.
Margaret Mitchell, DNP, FNP-C: A native Memphian, Maggie graduated Summa Cum Laude from the University of Memphis and earned her Doctorate of Nursing Practice from the University of Tennessee Health Science Center. As a nurse, she worked in primary care with Le Bonheur Pediatrics and following her NP program, she worked in Nashville as a Family Nurse Practitioner. Maggie has served as a Tennessee Promise Mentor and is on the UTHSC Honor Council; she has participated in the Nursing in Diverse Cultures program in Ecuador and is a member of Sigma Theta Tau Honor Society of Nursing. She lives in east Memphis with her husband, David, their daughter, Elizabeth, and two pups, Ruthie, and Gus.
Brittaney Gillespie, NP: I joined Lifesigns in March 2026 after completing my Doctorate of Nurse Practice, Family Practice Nurse in 2025 from Baylor University. Before Lifesigns, I was with Le Bonheur Children’s Hospital in Pediatric Intensive Care for over 7 years after completing my BSN in Nursing Science from Baptist College of Health Sciences.
Ashley Chatman, MSN, WHNP-BC: I decided to expand my experience and education by earning my Master of Science in Nursing from the University of South Alabama after several years as a registered nurse and medical assistant. Before joining Lifesigns in April 2026, I had over 18 years of experience in health care with Women’s Health Specialist in Germantown, the Department of Veterans Affairs Medical Center, Shelby County Jail and Signify Health. Volunteering is very important to me and I am passionate about Church Health Center and A Step Ahead Foundation.