Raphael Kellman, M.D. | Functional Medicine Doctor in NYC

Advanced Functional Medicine and Microbiome Restoration

Dr. Raphael Kellman is a best-selling author and a pioneer in functional and microbiome medicine.

His mission is to help patients like you rediscover their vitality. You’ve tried other doctors, even functional medicine doctors, but your symptoms haven’t improved. But have you truly reset your gut microbiome?

Through personalized wellness plans, advanced diagnostics, and modern therapies, Dr. Kellman gets to the root cause. He puts over a decade of experience to work. And his patients leave feeling better than ever.

Want to Know the Real Reason Why You’re Sick?

Many patients come to us for a wide variety of unexplained symptoms. Brain fog, fatigue, bloating, inflammation, weight gain, chronic pain – the list goes on and on.

A pill isn’t going to resolve these issues. A basic supplement plan won’t help either. You need a doctor who can diagnose you with exact precision. He has helped countless patients. His treatments are designed to activate the healing process and help you find answers. Most cases can be boiled down to a simple process.

Heart Pumps Blood

The heart keeps your body alive by pumping oxygen-rich blood to every cell. This steady flow delivers nutrients, removes waste, and gives you energy for daily life.

Kidneys Filter the Blood

Your kidneys clean the blood by removing toxins and balancing fluids. They help control blood pressure and keep your body’s internal environment stable and healthy.

Microbiome Heals

The gut’s good bacteria, known as the microbiome, support digestion, reduce inflammation, and strengthen immunity. When your gut is balanced, your whole body feels better.

Root Cause Wellness. Like Cleaning Up the Hudson River

Since we’re New York City’s premier functional medicine clinic, let’s use an analogy we can all understand.

Functional medicine is like trying to clean up the Hudson River—you can’t just add more fish or plant shrubbery along the banks and expect the ecosystem to thrive. If the water stays polluted, those efforts won’t last.

The real solution starts with cleaning the river itself—removing the toxins, stopping waste from entering the current, and allowing the environment to heal. Once the water is clean, life can return. Fish repopulate, plants grow, and the ecosystem begins to sustain itself again. The same principle applies to your body: you can’t just add supplements or healthy foods to a toxic system and expect wellness.

ou have to clear out what’s harming you first, and then your body will naturally rebuild and thrive.

Conditions That Respond to Advanced Functional Medicine

Dr. Kellman is an expert in the complex and confusing. He’s not a specialist in just one disease. Instead, he uses his diagnostic tools to find the root cause. That’s why this list of conditions is just the beginning. If you’re struggling with mystery symptoms that haven’t been explained by other doctors, you need to reach out to Dr. Kellman and his team.

Chronic Fatigue
Autoimmune Conditions
Thyroid Conditions
Neurodegenerative Diseases
Cancer
IBS & Gut Issues
Chronic Pain
Heavy Metal Toxicity
Mold Toxicity
Weight Loss

Meet Dr. Kellman | The Most Experienced Doctor in Functional Medicine

Dr. Kellman pioneered a revolutionary approach to health known as Microbiome Medicine—a field he developed long before it became a mainstream topic in research and conventional care. He was among the first physicians to recognize the microbiome’s deep connection to nearly every aspect of human health, from chronic disease to overall vitality. While much of medicine is only now beginning to understand this link, Dr. Kellman has spent years using the microbiome as both a key to identifying root causes and a pathway to reversing illness.

Internationally recognized for his expertise, Dr. Kellman is also known for his advanced diagnostic testing, particularly his precise and comprehensive thyroid evaluations. Thyroid disease is widespread, yet many people suffer for years without accurate diagnosis or effective treatment. Through his innovative testing methods and deep clinical insight, Dr. Kellman has helped countless patients in New York City and across the nation uncover the true source of their symptoms and achieve lasting healing.

Dr. Kellman has been featured on CBS, CBN, Yahoo! Finance, and many other national outlets.

Dr. Kellman | Best-Selling Author on Microbiome and Healing

Explore Dr. Raphael Kellman’s groundbreaking books on functional medicine, the microbiome, and the mind-body connection. Each book offers practical insights and science-based strategies to help you restore balance, boost vitality, and achieve lasting wellness from the inside out.

Advanced Therapies at Our World-Class Facility

NovoTHOR Whole Body Red Light Therapy uses red and near-infrared light to reduce inflammation, speed recovery, and boost energy at the cellular level. This treatment enhances mitochondrial function, helping the body naturally repair tissue and reduce pain.

Pulsed Electromagnetic Field Therapy applies electromagnetic waves to stimulate cell repair, improve circulation, and relieve pain. It is often used to enhance bone healing, reduce inflammation, and support overall cellular health.

Magnesphere Therapy is a relaxation technology that uses magnetic fields to balance the autonomic nervous system and reduce stress-related symptoms. By promoting deep relaxation, it can help improve sleep, mood, and physical recovery.

Peptide Therapy uses short chains of amino acids to help the body heal, improve hormone balance, and enhance energy, metabolism, and recovery. Each peptide targets specific functions such as muscle repair, cognitive health, or immune support.

IV Therapy delivers vitamins, minerals, and hydration directly into the bloodstream for fast and effective nutrient absorption. This therapy can boost energy, strengthen immunity, and help the body recover from illness, fatigue, or dehydration.

The Sunetics Hair Growth Laser is a non-invasive laser treatment that stimulates hair follicles to promote thicker, healthier hair growth. It increases blood flow to the scalp and can slow or even reverse hair thinning over time.

Our Weight Loss program provides a personalized plan focused on nutrition, activity, and lifestyle habits to promote sustainable fat loss and metabolic health. Each plan is tailored to individual goals, helping patients lose weight while improving overall wellness.

Patient Reviews

Stay Informed. Heal Smarter.

Join Dr. Kellman’s community and get expert tips on functional medicine, microbiome health, and holistic healing—straight to your inbox. Discover science-backed insights and updates from NYC’s leading functional medicine practice.

Become a Patient at New York City’s Advanced Functional Medicine Practice

Dr. Kellman goes beyond conventional care to restore your body’s natural balance and vitality. Our process begins with precise testing to uncover what’s really happening inside your body. We then work to prime your system—supporting detoxification, optimizing nutrient absorption, and rebuilding microbiome health—before moving into a phase of full restoration.


Here’s the truth. If a practitioner claims to get to the root cause but never addresses the microbiome, they aren’t truly getting to the root. The microbiome affects every aspect of wellness, from digestion and immunity to hormones, metabolism, and mood. Dr. Kellman’s pioneering approach to Microbiome Medicine ensures that your care starts at the true foundation of health.


Learn why we’re New York City’s most trusted clinic. Schedule your consultation with Dr. Kellman and begin your journey toward lasting wellness.