WHAT IS FUNCTIONAL MEDICINE?

Quick takes

In the News: With the administration nominating Dr. Casey Means for Surgeon General, mentioning her experience practicing functional medicine, it is a good time to ask: What exactly is this approach, and why does it generate both enthusiasm and skepticism?

Core Principles of Functional Medicine

• Seek the Root Cause: Rather than just treating symptoms, we investigate underlying factors driving disease processes. Conventional physicians also think they are treating the underlying cause. For example, if a person has a urinary tract infection, we kill the bacteria responsible. But in functional medicine, we would also ask: Why did this happen? What can we do to prevent a recurrence?

• Bridge The Implementation Gap: Conventional colleagues argue that we don’t know the origin of many conditions. But we know more than we think. Functional medicine utilizes scientifically-backed interventions that haven't yet been incorporated into standard guidelines—bridging the gap between research publication and clinical implementation.

• Prefer Solutions That Fix The Thing That Went Wrong: For example, depression is not a Lexapro deficiency, thus we look for other causes, maybe a combination of causes.

• Work “With” The Body: Most people either lack something (nutrient, practice) or have too much of something (virus, toxin). Addressing this goes a long way. In my practice it’s vitamin D, omega 3s, magnesium, stress reduction, movement, time outside, a daily rhythm, and whatever I can do to improve the ecology of the gut microbiota, because we live in an environment full of pesticides, antibiotics, and stress.

• Adopt a Systems Biology Approach: The body functions as an interconnected network. What conventional medicine might treat as separate conditions (rash, irritable bowel, fatigue), functional medicine recognizes as probably related manifestations of common underlying imbalances.

• Conventional Colleagues: As a physician with 20 years in conventional family practice, then 15 years in functional medicine, a degree in public health, and a residency in preventive medicine, I apply the same scientific standards across all approaches.
  We have two issues however:

  • Many practitioners without a medical license give functional medicine advice, which might make it look to you like it’s not a serious field.

  • Some functional medicine doctors give high priority to the opinion of physicians they trust and their own experience, as opposed to the results of clinical trials which have sometimes proven to be biased

• Integrative Practitioners: As a field, we should be aware of which tools are clinical research-demonstrated and which are used based on a different level of evidence. Each may be contradicted in the future, through different mechanisms. We should limit the use of interventions lacking robust evidence.

• Patients: This approach means understanding your body as an integrated system, addressing fundamental imbalances with evidence-based tools, and developing personalized plans that consider your unique circumstances. It also means active participation in your health. We typically ask you to change your diet, adopt exercise and stress reduction, prioritize sufficient sleep and other practices.

Favorite Finds

Here are some foundational books that got many of us started:

• Jeffrey Bland, The Disease Delusion

• Mark Hyman, The Ultramind Solution, and UltraPrevention

• Terry Wahls, The Wahls Protocol

• Dale Bredesen, The End of Alzheimer’s Program

The Institute for Functional Medicine helps visitors Find A Practitioner

Deep Dive

My Journey: From Conventional to Functional

Like many functional medicine physicians, my path began with a personal crisis. After 20 years in conventional medicine, I faced a relative's illness that didn't respond to standard treatments. Determined to find solutions, I cautiously explored evidence-based alternatives. To my surprise, when I applied some of these approaches to my own health challenges, I experienced remarkable improvements—asthma symptoms entirely disappeared, osteoarthritis pain decreased, energy increased, gastrointestinal symptoms improved, acne cleared up, and I effortlessly lost 15 pounds.

At that point I felt a duty to learn the science behind the approaches I found so effective, so I could offer them to my patients.

Initial and Ongoing Training in Functional Medicine

I trained with the Institute for Functional Medicine (IFM), and over 5 years attended:

• Seven intensive modules covering approaches and cases centered on various body systems

• Monthly meetings with like-minded physicians also transitioning to a functional medicine practice approach

• A certification examination testing clinical applications and formal understanding

What makes functional medicine uniquely demanding is the constant evolution of knowledge. Each day, I conduct at least one deep literature search using tools like search engines, Consensus, Perplexity or Open Evidence to:

• Verify the latest research on suggested interventions

• Cross-check potential supplement-medication interactions

• Investigate emerging connections between symptoms and root causes

• Stay current on laboratory testing validity and interpretation

• Create guides for myself so I can use this knowledge in future situations

• Network with colleagues to share insights, key publications, tips, and experiences

Unlike conventional medicine where guidelines might update every few years, functional medicine requires daily learning to maintain scientific integrity.

What to Look For in a Functional Medicine Practitioner

Qualified practitioners typically have:

• A scope of practice relevant to your needs: diagnosis and treatment of illness is not in the scope of practice of all professions

• A reputable certification or active progress toward certification in functional or integrative medicine

• A commitment to evidence-based approaches

• Clear explanations of both the science and limitations of recommended approaches

• Transparent fee structures without supplement sales pressure

• A willingness to collaborate with your conventional providers: a blanket distrust of all conventional physicians is as illogical as blanket distrust of all integrative and functional physicians.

The Supplement Question

There are several categories of supplements:

• Substances our bodies naturally produce (CoQ10)

• Non-native compounds that modify biochemistry (curcumin, herbs)

• Essential nutrients difficult to obtain in sufficient quantities from food (magnesium, calcium)

• Performance enhancers (best avoided)

• Vitamins necessary for proper function

While many highlight concerns about supplement regulation (often valid), they overlook important nuances:

• Some nutrients can be reliably tested in the bloodstream (vitamin D, B12, zinc, omega 3s), so we can verify what may be in a given preparation

• Many are tested by 3rd party testing companies such as ConsumerLab and LabDoor

• Sometimes what we can test is the impact of a supplement on reducing blood pressure, inflammation, or cholesterol

What is Controversial

Functional medicine operates in the space between established knowledge and official guidelines—at best using science that exists but hasn't been codified into protocols, at worst using interventions with only preclinical or theoretical validity. This understandably creates tension with conventional approaches.

In an ideal world, we all learn from each other. While medicine rightfully seeks a preponderance of evidence, patients can't always wait for relief. Our fundamental difference lies in where we draw the line: should we use only fully approved treatments, partially approved options, or anything (safe) with even a slight chance of effectiveness?

The Gut Microbiome Example:

Science has clearly established connections between gut health and the immune system, nervous system, autoimmunity, and metabolic function. However, conventional medicine has no commonly used protocols addressing intestinal permeability ("leaky gut")—a concept well-established in basic science research. Yet there is research that can guide an approach to patients, and that is also worth the expense (commensurate with the suffering) and extremely unlikely to cause harm.

At one end is the conventional physician who completely ignores the situation. Patients understandably seek an alternative.

At the other end is the integrative practitioner who administers expensive testing and recommends complicated practices and pricey supplements. Each of these recommendations is science-based, some more than others, but the entire approach has not made it into the guidelines for gastroenterologists. Let’s look at our outcomes!

Understanding the Conflicts of Interest

I have no patience with the argument that physicians are grifters who just want to profit off of patients’ suffering. Each side levels this accusation at the other side, and I reject it completely. The people I’ve met in both conventional and functional medicine want to be effective. They enjoy fixing patients’ medical problems.

On the other hand, there are challenges to each approach. On the conventional side, there is the danger of having a limited set of tools, of moral injury and burnout, affecting up to 60% of physicians in most specialties. There are sometimes financial incentives for certain behaviors. On the integrative side, there is uncertainty regarding specific approaches, which we understand (from research in psychology) may result in providers adopting “motivated reasoning” which can ultimately serve their bottom line. However this is not the same thing as callously setting out to defraud or under-treat patients.

Conventional Medicine's Blind Spots

• Pharmaceutical influence extends beyond marketing to research design, data interpretation, and guideline development, and has resulted in skewing research results towards showing effectiveness for minimally effective medications, and downplaying adverse effects

• Many experts who sit on guideline committees receive significant industry funding

• As Goldman Sachs candidly admitted in a 2018 report, "curing patients is not a sustainable business model"—revealing a systemic preference for chronic disease management over resolution

• The revolving door between regulatory agencies and industry creates inherent conflicts

• There can be recommendation bias for offices owning X-ray machines and for surgeons recommending surgery

• Short appointments are incompatible with addressing multifaceted health issues

• Specialist silos fragment care in ways that contradict a systems biology understanding

Functional Medicine's Ethical Challenges

• Profit from supplement sales creates a risk for recommendation bias

• Investment-heavy technologies (neurofeedback, HBOT, ozone therapy, IV nutrient therapies) require high patient volume to recover costs

• Expensive protocols and programs may be marketed without proportionate evidence

• Cash-based practices create significant obstacles to financial access

Bridging the Divide

Transparency

• Disclose all financial relationships with supplement companies and technology providers

• When recommending supplements, provide brand options separate from the ones we derive profit from

• Regularly assess whether technologies in one’s practice deliver value proportionate to cost

Thoughtfulness

• Limit interventions to those with reasonable supporting evidence or low-risk/high-potential ratios

• Clearly label experimental approaches with appropriate informed consent

• Target advanced technologies only for conditions where conventional options have been exhausted

Integrity

• Francis Peabody famously said that “The secret of the care of the patient is in caring for the patient.” Adopt an attitude that we are stewards of our patients’ funds: we use them wisely.

• The ultimate goal is patient autonomy, not dependency on either supplements or medications, or even the physician

• Prevention and education should be tailored and thorough

The Respectful Path Forward

While conventional and functional medicine sometimes operate from different philosophical frameworks, both ultimately serve patients best when practitioners:

• Delineate a core set of practices that make sense to both

• Assume basic good will on all sides

• Understand where approaches differ and why

• Acknowledge the limitations of each approach

• Prioritize patient outcomes over dogma

• Commit to continuous learning and humility

We may never fully reconcile all differences between conventional and functional medicine—our value systems sometimes emphasize different priorities. However, by maintaining mutual respect and recognizing that each approach offers valuable tools, we can create a more complete healthcare system that serves patients more effectively than either model alone.