Meet your Flourish Care team
We believe healing happens through connection, collaboration, and truly personalized care. Our team brings together a unique blend of clinical expertise, warmth, and whole-person support—ensuring every patient feels seen, heard, and cared for at every step of their wellness journey.
Hillary Fredrickson, ND
Naturopathic Doctor | Founder
HILLARY FREDRICKSON, ND is a naturopathic physician who received her medical training at Bastyr University in Seattle and has been in clinical practice since 2004, opening her private practice in California in 2005. Over the years, she has worked with thousands of patients seeking deeper answers, holistic solutions, and compassionate care.
She is also the co‑founder of Cultivate Fertility, a specialty online practice focused on natural fertility, pregnancy, and reproductive wellness. Hillary is passionate about the power of natural medicine and loves collaborating with her patients to help them find a grounded, sustainable state of balance and vitality.
She is a mother of three (ages 21, 19, and 16), a lover of adventurous world travel, a home chef who delights in cooking for loved ones, and a firm believer in the healing power of laughter, dancing, and joy.
Jacqueline Chan
D.O. | Holistic Medicine Doctor
As a holistic medicine physician, Dr. Chan believes that compassion, presence and grace are crucial healing forces along with intelligently applied clinical knowledge.
Jacqueline Chan, D.O. graduated from Mount Holyoke College magna cum laude in philosophy in 1990 then did a short stint in an MBA finance program on Wall Street in New York City. Jacqueline decided her true calling was in medicine. In 1994 she graduated from Ohio University College of Osteopathic Medicine in the top 10 of her class and completed her Family Practice Residency in 1997. Jacqueline is Board Certified in Integrative Holistic Medicine and Neuromusculokeletal Medicine. Dr. Chan was drawn to Osteopathic Medicine because of it’s holistic and individualized approach.
Dr. Chan believes that health means more than the absence of disease. Optimal health includes operating out of the highest expression of our soul’s purpose.
She uses functional lab testing to assess for overall toxic burden, nutritional status, gut microbiome, brain chemistry, hormone levels, adrenal health and genetics. Dr. Chan also addresses more subtle energies that can affect our health, such as wi-fi and emotional or psychic stressors. Dr. Chan uses a wide array of treatment modalities that include the energetics of the body’s biofield, orthomolecular substances, herbal tinctures for endocrine support and anti-pathogen purposes, German homeopathic remedies for increasing organ functionality, IV nutrient therapy, Hyperbaric Oxygen Therapy, as well as hands-on osteopathic craniosacral therapy and energy balancing.
Dr. Chan is a member of the American Board of Integrative Holistic Medicine and the American Osteopathic Association as well as part-time faculty member of the Academy of Intuition Medicine.
She has presented on a panel for Dr. Oz at the Civic Center in San Francisco, completed a research study at the Institute of Frontier Science on the Biofield, and served as part-time faculty at Touro Medical School's Osteopathic Medical Department. She completed a Transformative Leadership Training program in 2014. She is currently serving as a core faculty member at the Academy of Intuition Medicine and presented at the Institute of Noetic Sciences on Energetic Awareness.
Jennifer Nathanson, NP
Nurse Practitioner | Functional Medicine Specialist
JENNIFER NATHANSON, MSN, NP-BC is a board-certified nurse practitioner with over 23 years of experience in healthcare and advanced training in functional and integrative medicine. Through both her professional work and her own health journey, Jennifer has seen how often patients feel unheard or unsupported within conventional care. She is passionate about offering a different experience — one that is thoughtful, collaborative, and focused on understanding the whole person, not just a diagnosis.
Jennifer works with patients who feel stuck in chronic symptoms such as fatigue, hormone changes, digestive concerns, immune imbalance, and ongoing inflammatory patterns. Her approach emphasizes identifying underlying contributors and creating clear, step-by-step plans using personalized nutrition, lifestyle support, and carefully chosen therapeutic tools. She emphasizes shared decision-making, taking time to explain options and working together with patients to choose next steps that feel realistic, supportive, and aligned with their goals.
Patients often describe Jennifer as grounded, thorough, and deeply compassionate. She brings a calm, supportive presence to care and is especially passionate about supporting women through midlife health transitions and complex life demands. With a Master of Science in Nursing from the University of California, San Francisco (UCSF) and certification through the School of Applied Functional Medicine, she brings both clinical training and a deeply patient-centered lens to her work, focusing on partnership, trust, and long-term healing.
Carolina Loiacono
Clinic Manager
CAROLINA LOIACONO ensures that the Flourish Marin Integrative Medicine clinic runs smoothly every day and that patients receive the specialized care for which our practice is known. As the Clinic Manager, she oversees operations, supports the clinical team, and ensures that every patient has a top-notch experience.
Known for her exceptional organizational skills and warm, grounded presence, Carolina keeps the many moving parts of a busy practice flowing with ease. She holds a Master of Social Work, specializing in Community Organizing, Planning, and Administration.
Outside of work, Carolina enjoys crafting, spending time with her nieces, Issa and Mila, and indulging in chocolate whenever possible.
Susie Bergen
Patient Coordinator
SUSIE BERGEN is our Patient Coordinator extraordinaire, guiding patients with care, clarity, and genuine kindness from their very first interaction. She ensures scheduling, communication, and support happen smoothly and with heart.
Beyond the clinic, Susie runs a woman‑owned, family‑operated essential oil company, carrying forward the legacy started by her mother, Nancy. She is passionate about natural wellness, plant‑based living, and creating offerings that support balance and connection.
When she’s not at the office, you’ll find Susie spending time with her horse DJ, kickboxing, baking delicious treats, or enjoying moments with her family.
LEAH MAST
Nurse
Leah Mast, BSN, RN earned her Bachelor of Science in Nursing from Montana State University. Raised on a farm and ranch, she developed a strong work ethic, deep sense of responsibility, and genuine appreciation for caring for others—values she brings into her nursing practice every day.
Leah is committed to providing compassionate, patient-centered care and believes in creating a calm, supportive environment where patients feel heard, informed, and comfortable. She values clear communication and takes pride in delivering thoughtful, attentive care tailored to each individual.
Outside of work, Leah is a proud mother of three. She enjoys spending time in nature, traveling, and cooking, which help her maintain balance and bring warmth and empathy to her role as a registered nurse.
Together, We’re Here to Support Your Wellness Journey
Our entire team shares one mission: to provide compassionate, integrative, patient‑centered care that helps you feel your best from the inside out. We proudly serve patients in Marin County and throughout the San Francisco Bay Area, California.
We're honored to walk with you toward lasting vitality and wellness.