Functional Medicine: What It Is, How It Works, and What to Expect

Functional medicine is an approach to care that looks for the factors behind chronic symptoms, such as nutrition, sleep, stress, genetics, and environment, instead of treating each symptom alone. It is practiced by licensed clinicians who spend more time on your history and often order extra lab tests before building a plan.

If your labs came back normal but you still feel tired, foggy, or unwell, this guide explains how the approach works, what the research does and does not show, and what a first visit looks like at Next Health in Ashburn, Virginia, and Bethesda, Maryland.

Key Takeaways

• Functional medicine looks for contributing factors behind chronic symptoms and builds a plan around food, sleep, stress, activity, and medical care when needed.
• It is meant to work alongside conventional care. It does not replace emergency or acute care.
• The research is still early. A 2019 Cleveland Clinic study found better quality of life scores in functional medicine patients, but it was observational and cannot show cause.
• Insurance coverage depends on the clinic and your plan, so ask your insurer before you book.
• A first visit at Next Health lasts about an hour on average and includes your history, a physical exam, and targeted lab tests.
• Next Health has locations in Ashburn, VA and Bethesda, MD, serving Washington DC, Maryland, and Northern Virginia.

What Is Functional Medicine?

Functional medicine is a model of care that asks why a person is ill, not only which condition they have. Cleveland Clinic describes it as an approach to chronic disease that weighs genetics, nutrition, stress, exposure to toxins, allergens, and gut health.

The plan that follows usually covers food, exercise, sleep, and mental and emotional health. Cleveland Clinic says it was the first US academic medical center to open a dedicated functional medicine program in 2014.

Some clinicians call this root cause medicine. Next Health explains the idea in its guide to root cause medicine.

How Does Functional Medicine Work?

Functional medicine works by gathering a detailed health history, ordering selected tests, and building a plan around the factors your clinician believes are contributing to your symptoms. Most visits follow four steps:

1. History. Your clinician reviews your medical timeline, medications, diet, sleep, stress, family history, and exposures.
2. Exam and testing. A physical exam and targeted lab tests show how your body is working.
3. Patterns. Your clinician looks for patterns, such as nutrient gaps, hormone changes, inflammation, or gut problems, that may help explain your symptoms.
4. Plan. Treatment may include nutrition changes, exercise, sleep and stress support, supplements, and medical therapies. Follow-up visits adjust the plan.

Because the approach relies on clinical judgment, functional medicine treatment can differ from one practitioner to the next. The clinician you choose matters.

What Is a Functional Medicine Doctor, and Are They MDs?

A functional medicine doctor is a licensed clinician who uses the functional medicine approach in practice. It is a way of practicing, not a separate medical license, so some functional medicine practitioners are MDs or DOs, while others are nurse practitioners, dietitians, or other licensed professionals. Cleveland Clinic’s team, for example, includes physicians, nurse practitioners, registered dietitians, and health coaches.

Ask any functional medicine practitioner about their license, board certification, and training before you book. At Next Health, Dr. Habib is an internal medicine physician who trained at the University of Sheffield Medical School in England and completed his internal medicine residency at Baystate Medical Center in Massachusetts in 2000. He added integrative and functional medicine to his practice in 2006.

How Is Functional Medicine Different From Conventional Medicine?

When people compare functional medicine vs conventional medicine, the main difference is emphasis. Conventional medicine centers on diagnosing a condition and treating it with tools such as medication, procedures, and surgery, while functional medicine adds a closer look at lifestyle and other contributing factors, usually with longer visits.

Conventional care is essential for emergencies, infections, and injuries, and functional medicine does not replace it. The two can work together. Cleveland Clinic states that its functional medicine team collaborates with conventional clinicians and does not replace them.

Is Functional Medicine the Same as Integrative Medicine?

No, they overlap but are not the same. The National Center for Complementary and Integrative Health, part of the National Institutes of Health, explains that integrative health brings conventional and complementary approaches together in a coordinated way to care for the whole person.

The difference between functional medicine and integrative medicine is mostly one of scope. Integrative medicine is the broader term for combining approaches, while functional medicine is a specific model that centers on the contributing factors behind chronic illness. Many clinics use both. Dr. Habib added integrative and functional medicine to Next Health in 2006.

What Conditions Do People See a Functional Medicine Doctor For?

People most often look for a functional medicine practitioner when they have long-standing or hard-to-explain health problems. Cleveland Clinic lists arthritis, asthma, autoimmune diseases, diabetes, digestive disorders, thyroid disorders, metabolic syndrome, and prediabetes among the conditions its team sees.

Nutrition, sleep, stress, and activity changes may help some people manage these conditions, but results vary, and functional medicine should sit alongside standard medical care. The same applies to questions about functional medicine for thyroid problems or gut health: keep your current treatment plan unless your own doctor changes it.

Next Health also has dedicated pages on related topics, including heart disease prevention, sleep issues, and medical weight loss.

Is Functional Medicine Legit, and What Does the Research Say?

Functional medicine is a real clinical approach used by licensed clinicians, but the research on the full model is still limited. Parts of it, such as better nutrition and regular activity, match what public health agencies already recommend. In its current Chronic Diseases in America overview, the CDC names poor nutrition and lack of physical activity among the key lifestyle risks for chronic disease and reports that 6 in 10 US adults have a chronic disease, with 4 in 10 having two or more.

In 2019, Cleveland Clinic researchers published what they describe as the first retrospective cohort study of the functional medicine model in JAMA Network Open. They compared 1,595 patients in the Center for Functional Medicine with 5,657 primary care patients over two years. The functional medicine group showed improvements in health-related quality of life on a patient questionnaire called PROMIS.

The study looked back at existing records, so it shows an association, not cause. The researchers said the results may reflect the model itself, the kind of patients who choose it, or belief in the treatment, and that future studies following patients forward in time are needed. Ask any clinic what evidence supports each test and treatment it recommends.

What Happens at a First Functional Medicine Appointment?

A first functional medicine appointment is a long visit that covers your history, a physical exam, and a plan for next steps. At Next Health, Dr. Habib spends about an hour on average with new patients.

During that functional medicine consultation, he:

1. Reviews your health timeline, including past medical events, medications, diet, sleep, stress, environmental exposures, and family history.
2. Performs a physical exam.
3. Orders targeted lab tests and other diagnostics when needed.
4. Begins building a treatment plan around your results and goals.

Bring a list of your medications and supplements, recent lab results, and the questions you most want answered.

What Tests Does Functional Medicine Use?

Functional medicine testing often includes blood work beyond a standard panel, and sometimes other specialty tests, chosen based on your symptoms and history. Functional medicine labs are meant to give your clinician more detail about how your body is working.

More testing is not always better. Cleveland Clinic notes that its team helps most patients meet their needs without extensive testing or supplements. Ask your clinician why each test is ordered, what the result could change, and what it will cost.

Next Health also offers Bio Age and DNA Age programs for patients interested in testing related to aging.

Is Functional Medicine Covered by Insurance, and What Does It Cost?

Coverage depends on the clinic and your plan. Some practices bill insurance for visits, others use a self-pay model, and specialty labs are often handled differently from routine ones. Call your insurer before you book to ask what is covered.

Functional medicine cost depends on how long your visits are, which tests are ordered, and which treatments are in your plan. Next Health does not list prices in this article, so contact the team for current fees and payment options.

How Does Dr. Habib Practice Functional Medicine at Next Health?

Dr. Habib uses functional medicine alongside conventional tools, guided by three goals: Predict, Prevent, and Prolong. Next Health was founded in Ashburn, Virginia, in 2001, and according to the clinic, Dr. Habib has more than 30 years of clinical experience in internal medicine, functional medicine, and longevity care.

• Predict: use diagnostics to identify health risks before symptoms appear.
• Prevent: address contributing factors with personalized, primarily drug-free plans.
• Prolong: support not only lifespan but years lived with energy, strength, and quality of life.

Depending on your evaluation and lab results, a plan may include nutrition and lifestyle changes along with services such as IV vitamin therapy, hyperbaric oxygen therapy, chelation therapy, glutathione boost, or regenerative therapies. These are not part of every plan, and Dr. Habib bases recommendations on your history and lab results. You can read more about him on the About page.

Where Can I Find a Functional Medicine Doctor Near Me in DC, Maryland, or Northern Virginia?

Next Health has two locations serving Washington, DC, Maryland, and Northern Virginia. Patients looking for functional medicine in Maryland can visit the Bethesda office, and patients in Northern Virginia can visit Ashburn. If you want a functional medicine doctor in Washington, DC, either location serves the area, including patients from Loudoun County and Montgomery County.

• Ashburn, Virginia: 44121 Leesburg Pike, Suite 115, Ashburn, VA 20147
• Bethesda, Maryland: 5101 River Road, Suite 106, Bethesda, MD 20816

To ask about an appointment, use the contact page or email info@nexthealthmed.com.

What Else Do Patients Ask About Functional Medicine?

Do I need a referral to see Dr. Habib?

No. Next Health does not require a referral. You can reach the team through the contact page to get started.

Can I keep taking my current medications?

Do not stop or change a prescription on your own. Dr. Habib works alongside your existing physicians, and any medication change should be discussed with the doctor who prescribed it.

How long does functional medicine take to work?

There is no standard timeline, and no clinic can promise a result. Changes to habits often take time to show up in symptoms and lab results, and the pace depends on your condition, your starting labs, and how consistently you follow the plan.

When is functional medicine not the right choice?

Emergencies, acute infections, and injuries need conventional emergency or acute care first. If you have chest pain, trouble breathing, or signs of a stroke, call 911.

Is functional medicine safe?

Nutrition, sleep, and activity changes are low risk for most people, but supplements, specialty tests, and other therapies can carry risks or interact with medications. Tell your clinician everything you take, and ask what evidence supports each recommendation.

This article is for general education and is not medical advice; it does not replace an evaluation by your own physician, and individual results vary.