Functional Medicine Doctor
You're unique. Your healthcare should be, too. A one-size-fits-all approach doesn't address the root cause of disease. Using the functional medicine approach, we partner with you by listening to your unique story and providing care that addresses the source of your chronic disease or health issues.
Are you living with unexplained symptoms, chronic fatigue, or persistent health challenges that just won’t resolve? It can feel exhausting—especially when traditional medicine focuses only on symptom management.
You deserve a functional medicine doctor who goes deeper. In my practice, I utilize the functional medicine approach, combined with my specialized expertise as a functional medicine nutritionist, to help you reclaim your energy, health, and vitality. That means we look beyond the surface to understand the real *why* behind your symptoms—exploring the biochemical, environmental, and nutritional factors that may be disrupting your wellbeing.
Unlike conventional care that often uses a one-size-fits-all protocol, a functional health practitioner customizes your care. Your story, your genetics, your lifestyle, and your health history all matter. We take the time to understand your whole picture—not just your lab results—so we can design a plan that supports your body’s natural ability to heal.
We Look Where Others Don’t
Using advanced diagnostic testing and over 40 years of clinical experience, we help identify what’s been missed—like:
● Hidden infections
● Hormonal imbalances
● Nutritional deficiencies
● Toxic exposures
● Gut and immune dysfunction
By addressing these root causes, we create targeted, sustainable solutions that incorporate the best that functional nutrition and functional medicine have to offer. This combined approach supports the multiple systems of the body all at once—often leading to lasting and transformative results.
Whether You’re…
● Struggling with digestive issues or autoimmune symptoms
● Dealing with hormonal imbalance, brain fog, or fatigue
● Or simply ready to optimize your health and feel your best…
…functional medicine can help bring clarity, direction, and real healing.
Functional Medicine Can Make All the Difference to Your Health.
Learn MoreYour Next Step Toward Wellness
Stop settling for temporary fixes.
If you’re tired of being told “everything looks normal” when you know something isn’t right, it’s time to explore a deeper kind of care that functional medicine provides. Let’s begin your healing journey together—one step at a time.
Contact Us to schedule your personalized consultation today and take the first step toward restoring your health.
Your body is wise. It wants to heal. With the right support, it can.
Is your current health routine truly contributing to an improvement in your overall wellness? Now you can know. Our functional health testing includes over 100 markers to provide you with the information and clinical expertise you need to take your health from where you are to where you want to be.
- Comprehensive Lab Testing from A-Z: Allergies, Autoimmune, Cardiometabolic, Early Cancer Detection, Environmental Toxins, Gut Microbiome, Hormones, Immunologic (Covid; Long-Covid; Tickborne Illnesses & more), Longevity, Mold & Mycotoxins, Nutrient, Stress, and more.
- Customized Care based on 40 Years of Clinical Expertise: Ready to live healthier, longer? You can experience your best health now by identifying and addressing the underlying factors that negatively impact your physical and mental health.
- Cutting-edge EpiGenetic Testing: Extend and revitalize your health with advanced testing that measures 75 key longevity biomarkers to give you personalized insights and actionable steps to help you improve your health and slow the aging process.
Looking for healthcare that gets to the root cause of your health issues?
Start Your Journey TodayFocus Areas
Dr. Sarah Williams, DC
We look forward to providing you with the functional medicine care and support you need to reach your health goals and achieve wellness.
Learn More About Us
The Patient Journey
- StepCollect Your Information
- StepPersonalized Consultation
- StepFunctional Lab Testing
- StepCreating Your Wellness Plan
- StepFollow-up
Visit - StepIndividualized Health Plan
- StepMeeting Your Health Goals
- StepOptimizing Health
Testimonials
Dr Sarah Williams is truly a pivotal partner in my healthcare. She embodies holistic health in every way. She has helped transform my physical health, uncovered invaluable genetic information while maintaining my emotional well-being. She is an evidenced-based practitioner on the cutting edge of science-based medicine. For me she has filled a great void in my health team and my family and I rely on her unparalleled expertise for everything from the common cold, emotional struggles, and weight loss, to managing Celiac Disease and Multiple Sclerosis. Dr. Williams is a unique and skilled professional who provides invaluable insight. I am deeply grateful for her dedication.
My impression upon consulting Dr. Williams was that, for the first time, I was talking with someone who actually practices good medicine. Her practice is to understand and treat causes, not just treat symptoms. For fifty years I have had moderate to severe gastric and related issues. It now appears that they were all caused by a combination of food allergies that went undiagnosed and the aftermath of pharmaceuticals. After three weeks I told my wife that I was just about at the stage of saying that I never knew that the way I now feel (pain and symptom free) is the way one is supposed to feel.
After many frustrating rounds of different treatments to attain clearer skin including birth control pills, antibiotics, and skin care regimens over a two year period, I saw instant results, literally within days, under Dr. Sarah Williams care. With a change in my diet combined with nutritional supplements and homeopathic remedies, my skin cleared up immediately. I sound like an infomercial, I know, but this truly works! Thank you Dr. Sarah!
I recently had a colonoscopy. My last scope, about 6 years ago, showed polyps that the doctor’s notes that I saw apparently put me at elevated risk of colon cancer.
As I expected, my recent colonoscopy was completely clean. I attribute that outcome entirely to your diagnosis of wheat in less than one minute that dragoons of doctors with invasive and painful tests couldn’t figure out in 50 years, followed by your course of treatment. Again, my profound thanks.
- Immunometabolism describes the powerful connection between the immune system and metabolism. These two systems constantly communicate to regulate inflammation, energy production, blood sugar balance, and...
- Your Healing Journey Starts HereThis blog was created for those of you who may be struggling with your health, but aren’table to begin care in...
- Chronic fatigue, brain fog, poor sleep, feeling weak or lightheaded are just of few of the signs of iron deficiency anemia. While iron deficiency anemia...
Frequently Asked Questions
What is Functional Medicine?
Functional medicine uses a personalized approach to uncovering and addressing the root cause(s) of your health issues. Your health is more than just the sum of your symptoms. Functional medicine views the body as one integrated system and seeks to uncover the underlying causes of illness in order to restore health and vitality. While two people may have the same symptoms and medical diagnosis, they often have different underlying causes, making the functional medicine approach the best way to improve health and promote well-being. Dr. Williams takes an individual approach to each patient in order to identify those specific factors that triggered the change in their health.
How is Functional Medicine Different from Conventional Medicine?
Conventional medicine often treats only the symptom. In contrast, Functional Medicine aims to fix the source of health issues. It emphasizes a customized approach, focusing on the individual person and their unique health needs.
Can Functional Medicine Help With Chronic Conditions?
Yes! Functional Medicine is particularly beneficial for addressing the underlying causes of chronic conditions. By targeting the underlying cause of a chronic condition, functional medicine can reduce symptoms, improve health, and restore vitality.
What specific kinds of chronic conditions can functional medicine help with?
Functional medicine is all about getting to the root of chronic health issues—not just managing symptoms. It’s especially helpful for people dealing with:
- Digestive problems like IBS, reflux, constipation, or bloating
- Thyroid and adrenal imbalances
- Hormonal Imbalances in men and women
- Blood sugar issues, insulin resistance, and type 2 diabetes
- Heart health concerns like high blood pressure or elevated cholesterol
- Chronic fatigue and fibromyalgia
- Weight gain
- Joint Pain
- Migraines, anxiety, and mood imbalances
- Skin issues like eczema, acne, or rosacea
- Asthma, allergies & other respiratory issues
- Autoimmune conditions (like Hashimoto’s, lupus, or RA)
- Lyme Disease & Co-Infections
- Chronic Lyme & Long Covid
- Mold & Other Environmental Exposures
- General health optimization, prevention, and detoxification support
What types of conditions does Dr. Williams specialize in?
She specializes in treating complex and chronic conditions such as chronic Lyme disease, long COVID, autoimmune disorders, chronic fatigue, as well as digestive disorders, skin problems, elevated cholesterol or blood sugar and hormonal imbalances. Her approach focuses on identifying the root causes of symptoms and creating personalized treatment plans for each patient.
How does Dr. Williams approach patient care?
Dr. Williams is committed to helping patients achieve lasting wellness and vibrant health. She uses comprehensive testing and integrative therapies to address a wide range of health issues, from food sensitivities to joint pain and other chronic diseases.
How is functional testing different from regular lab work?
Traditional labs often look for disease and use wide “normal” ranges. Functional testing focuses on optimal health—it identifies imbalances before they become problems.
Some examples of the testing we use include:
- Advanced stool testing to check digestion, microbiome health, and inflammation
- Food sensitivity panels
- Hormone metabolite testing (like the DUTCH test)
- Nutrient testing (vitamins, minerals, omega-3s)
- Genetic screening for detox pathways and chronic disease risk
- Mold and mycotoxin testing
- Environmental toxin and heavy metal analysis
Will I have to take supplements forever?
Not at all. Supplements are usually short-term tools to support healing. Once your body regains balance, many of them can be reduced or stopped. We’ll reassess along the way, and focus on maintaining your results with real food, lifestyle habits, and natural rhythms—not lifelong pill plans.
I’ve tried everything—can functional medicine still help?
Yes. Many of our patients come to us after feeling dismissed or frustrated by years of unexplained symptoms and failed treatments. Our in-depth, investigative approach often reveals root causes like:
- Lingering gut infections (like parasites or Candida)
- Mold exposure or chronic inflammation from environmental toxins
- Leaky gut and food sensitivities
- Detox challenges tied to genetics or toxin buildup
By taking time to understand your story and running the right tests, we often uncover answers that other providers have missed. And more importantly—we create a functional health plan that finally helps you move forward.
Where does Dr. Sarah Williams practice, and what is her experience?
Dr. Sarah Williams is a functional medicine practitioner based in Concord, Massachusetts, with over 40 years of experience. She provides personalized and integrative care to patients in Concord and across Massachusetts. She also offers convenient telehealth visits for her patients.
What is Functional Medicine?
Functional medicine uses a personalized approach to uncovering and addressing the root cause(s) of your health issues. Your health is more than just the sum of your symptoms. Functional medicine views the body as one integrated system and seeks to uncover the underlying causes of illness in order to restore health and vitality. While two people may have the same symptoms and medical diagnosis, they often have different underlying causes, making the functional medicine approach the best way to improve health and promote well-being. Dr. Williams takes an individual approach to each patient in order to identify those specific factors that triggered the change in their health.
How is Functional Medicine Different from Conventional Medicine?
Conventional medicine often treats only the symptom. In contrast, Functional Medicine aims to fix the source of health issues. It emphasizes a customized approach, focusing on the individual person and their unique health needs.
Can Functional Medicine Help With Chronic Conditions?
Yes! Functional Medicine is particularly beneficial for addressing the underlying causes of chronic conditions. By targeting the underlying cause of a chronic condition, functional medicine can reduce symptoms, improve health, and restore vitality.
What specific kinds of chronic conditions can functional medicine help with?
Functional medicine is all about getting to the root of chronic health issues—not just managing symptoms. It’s especially helpful for people dealing with:
- Digestive problems like IBS, reflux, constipation, or bloating
- Thyroid and adrenal imbalances
- Hormonal Imbalances in men and women
- Blood sugar issues, insulin resistance, and type 2 diabetes
- Heart health concerns like high blood pressure or elevated cholesterol
- Chronic fatigue and fibromyalgia
- Weight gain
- Joint Pain
- Migraines, anxiety, and mood imbalances
- Skin issues like eczema, acne, or rosacea
- Asthma, allergies & other respiratory issues
- Autoimmune conditions (like Hashimoto’s, lupus, or RA)
- Lyme Disease & Co-Infections
- Chronic Lyme & Long Covid
- Mold & Other Environmental Exposures
- General health optimization, prevention, and detoxification support
What types of conditions does Dr. Williams specialize in?
She specializes in treating complex and chronic conditions such as chronic Lyme disease, long COVID, autoimmune disorders, chronic fatigue, as well as digestive disorders, skin problems, elevated cholesterol or blood sugar and hormonal imbalances. Her approach focuses on identifying the root causes of symptoms and creating personalized treatment plans for each patient.
How does Dr. Williams approach patient care?
Dr. Williams is committed to helping patients achieve lasting wellness and vibrant health. She uses comprehensive testing and integrative therapies to address a wide range of health issues, from food sensitivities to joint pain and other chronic diseases.
How is functional testing different from regular lab work?
Traditional labs often look for disease and use wide “normal” ranges. Functional testing focuses on optimal health—it identifies imbalances before they become problems.
Some examples of the testing we use include:
- Advanced stool testing to check digestion, microbiome health, and inflammation
- Food sensitivity panels
- Hormone metabolite testing (like the DUTCH test)
- Nutrient testing (vitamins, minerals, omega-3s)
- Genetic screening for detox pathways and chronic disease risk
- Mold and mycotoxin testing
- Environmental toxin and heavy metal analysis
Will I have to take supplements forever?
Not at all. Supplements are usually short-term tools to support healing. Once your body regains balance, many of them can be reduced or stopped. We’ll reassess along the way, and focus on maintaining your results with real food, lifestyle habits, and natural rhythms—not lifelong pill plans.
I’ve tried everything—can functional medicine still help?
Yes. Many of our patients come to us after feeling dismissed or frustrated by years of unexplained symptoms and failed treatments. Our in-depth, investigative approach often reveals root causes like:
- Lingering gut infections (like parasites or Candida)
- Mold exposure or chronic inflammation from environmental toxins
- Leaky gut and food sensitivities
- Detox challenges tied to genetics or toxin buildup
By taking time to understand your story and running the right tests, we often uncover answers that other providers have missed. And more importantly—we create a functional health plan that finally helps you move forward.
Where does Dr. Sarah Williams practice, and what is her experience?
Dr. Sarah Williams is a functional medicine practitioner based in Concord, Massachusetts, with over 40 years of experience. She provides personalized and integrative care to patients in Concord and across Massachusetts. She also offers convenient telehealth visits for her patients.