Functional Medicine is a personalized, systems-oriented model that empowers patients and practitioners to achieve the highest expression of health by working in collaboration to address the underlying causes of disease.

  • Functional Medicine offers a powerful new operating system and clinical model for assessment, treatment, and prevention of chronic disease to replace the outdated and ineffective acute-care models carried forward from the 20th century.
  • Functional Medicine incorporates the latest in genetic science, systems biology, and understanding of how environmental and lifestyle factors influence the emergence and progression of the disease.

Dr. Fitzgerald received her doctorate of naturopathic medicine from National College of Natural Medicine in Portland, Oregon.

Physician, Clinic Director

Dr. Fitzgerald received her doctorate of naturopathic medicine from National College of Natural Medicine in Portland, Oregon.

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Dr. Kenneth Litwin received his medical degree from Allegheny University of the Health Sciences and has been in practice for 19 years. Dr. Litwin specializes in Internal Medicine.

Kenneth A. Litwin, MD FACP IFMCP, is a highly respected, board-certified Internal Medicine and Functional Medicine physician.

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Stacey Cantor-Adkins

Stacey Cantor-Adkins MD, MS, IFMCP, received her MD degree from Stanford University, and then trained as a cardiac anesthesiologist

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Elizabeth Bird, MD FAAP

Elizabeth Bird, MD, FAAP, IFMCP, graduated from The Yale University School of Medicine where she was awarded both the American Medical Women’s Association Glasgow Memorial Award and New England Pediatric Society Prize.

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Darisa Espinal

Darisa Espinal, ND, MS, received her doctorate in Naturopathic Medicine at the University of Bridgeport. She earned her BS in Biology from the University of Hartford and completed her Master of Science in Human Nutrition from the University of Bridgeport. She is currently licensed as a naturopathic physician in the State of Connecticut.

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Dr. Rachel Surprenant

Dr. Rachel Surprenant is a licensed naturopathic physician with a focus in functional medicine approaches to women’s health.

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All nutrition appointments are available remotely, conveniently fitting into your life and your schedule no matter where you are or what you’re doing.

All of our Functional Nutritionists are trained and experienced in Functional Medicine through our clinic and the Institute for Functional Medicine. Your nutritionist will help you uncover the root causes of your issues, using detailed histories and functional laboratory testing (often included in your package), and create a highly-tailored Functional Medicine plan just for you.

Our nutrition team also has the benefit of ready access to myself and Dr. Litwin during our weekly Clinical Grand Rounds, to consult on your case should that be needed.

Lara Zakaria RPh MS CNS

Lara Zakaria PharmD MSc CNS CN CDN is a Nutritionist, specializing in Functional Medicine. She uses scientific evidence as well as positive psychology to inspire patients to use whole food, herbs and lifestyle modification to achieve their health goals.

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Gretchen DePalma, MS CNS

Gretchen DePalma, MS CNS Nutritionist   Book an Appointment   Contact Phone: (203) 304-9502 Email:   Social links: Biography Gretchen DePalma, MS CNS, is a Certified Nutrition Specialist. She holds a Master of Science degree in Nutrition and Integrative Health from Maryland University of Integrative Health and a Bachelor of Science in Finance from…

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Jessica Kovalchik, DC MS CNS LDN

Jessica Kovalchik, DC MS CNS LDN CDN Nutritionist   Book an Appointment   Contact Phone: (203) 304-9502 Email:   Social links: Biography Jessica Kovalchik, DC MS CNS LDN CDN, is a Certified Nutrition Specialist and Chiropractor. She received her Doctorate of Chiropractic in 2011 and her Master of Science in Applied Clinical Nutrition in…

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We have a fabulous, customer service driven team waiting to assist you.
Please do not hesitate to seek out support or guidance regarding any of your questions or concerns. We love to hear your compliments, too!

Karen L. Herb, MS CNS LDN

Chief Operations Officer

Karen L. Herb, MS CNS LDN holds a master’s degree in Functional Nutrition from the University of Bridgeport, CT.

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Karen Frank, CPC, our Sandy Hook Billings Manager is responsible for the timely and accurate preparation and distribution of customer invoices for the company and its subsidiaries. In addition, her department handles special invoicing as some joint-venture related invoicing.

Chief Financial Officer

Karen Frank has been working with Dr. Fitzgerald since 2009. She began her coding career in Long Island with the North Shore Health System.

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Rhonda is energetic, organized and motivated individual who handles all aspects of communication that leads and inspires everyone in the office at Sandy Hook.

Office Manager

Rhonda is a dependable team player with strong analytical, interpersonal, and communication skills.

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