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Functional Medicine Testing: Redefining Disease

Functional Medicine Testing: Redefining Disease

A FEW YEARS AGO, Jeffrey Bland quickly blurted out a sentence that speaks to the fundamental change happening in medicine today.

“Functional medicine is a disruptive technology that will overthrow the tyranny of the diagnosis.”

When I had dinner with Jeff a few weeks ago, he told me that at a recent conference of health care leaders in business and academia, the CEO of a major Pharma company said that in the future there will be no more drugs for blockbuster diseases, only blockbuster mechanisms. I used this as my opening line at the recent TEDMED conference where I introduced the concept of functional medicine to hundreds of innovators, entrepreneurs and health care leaders.

But this is abstract. I am a practicing physician and what I need to know every day is how to do I properly diagnose and treat disease.  If we are redefining disease based on causes and mechanism and not ICD-9 labels, then how do I navigate, what questions do I need to ask, what tests can help me understand mechanisms and pathways and function and not simply give symptoms a diagnostic code that tells me little of what’s at the root of my patient’s suffering.

Conventional medicine is the medicine of WHAT – what disease, what pill.

Functional medicine is the medicine of WHY — why is this symptom occurring now and in this way.. what’s at the root.

In the article for this week, I explore the need to redefine disease and to refocus diagnostic testing to assess the causes, to look at dysfunction in pathways use that to create a map to treat patients more effectively.

I will be sending out a weekly newsletter to help practitioners better understand and apply functional medicine, sharing some of the clinical pearls and observations and reviews of the research I have made over the last 15 years.  I will also be introducing a toolkit for practitioners to share what I have learned in my practice and a quickstart guide to functional medicine.  Please be patient with me as I have a lot on my plate, but am committed to helping provide this to practitioners over the next year.  Also feel free to use my blogs and videos to help explain functional medicine to your patients.  These resources are free and open to everyone.

This week’s article is called Functional Diagnostics: Redefining Disease. And here’s a short excerpt. Next week I will share what I see as the biggest problem that leads to poor or ineffective clinical outcomes — doing the right thing in the wrong order and how to do things in the right order to get the best outcomes.


Functional Diagnostics: Re-defining Disease

In the assessment of a patient today, a new roadmap is available, one based on networks of function and causality, on a new architecture of thinking and evaluation. It is a diagnostic medicine focused on patterns and disruptions in molecular pathways leading to disturbed function.  The declaration of a clinical disease is only a waypoint on the continuum of illness.


How, then, can we face a patient viewing their symptoms through new lenses?  What questions must we ask? How can we deduce proximal causes from diverse symptoms and measurements of physiology and biochemistry?  How can we systematically reduce impediments to health and restore optimal function and the capacity for self-regulation and healing?

A new framework for diagnostic evaluation may be called functional diagnostics.  Rather than assessing pathology, functional diagnosis assesses genetic predisposition, functional reserve, metabolic capacity, variations in physiologic functioning, diurnal and cyclic variation, and early tissue injury.  Inquiry into the dynamic processes of the “metabolome” allows personalization of therapy.  Questions of sensitivity and specificity break down under the light of a continuous, web like, network of function.  Disease is not a discrete phenomenon, on or off, defined by this or that test, or this or that descriptive disease definition (for example, meets 2 major and 4 minor criteria).

Read more.

Mark Hyman MD is the Medical Director at Cleveland Clinic’s Center for Functional Medicine, the Founder of The UltraWellness Center, and a ten-time #1 New York Times Bestselling author.

Comments (9)

  • I want to thank Dr. Hyman for his continued work in the field of functional medicine. While researching for my book, I was introduced to the field of functional medicine and was immediately attracted to what I believe is the practice of true HEALTHcare. Your willingness to share your knowledge unselfishly with other physicians is greatly appreciated. I look forward to your ongoing contributions to this growing field.

    “All great truth goes through three phases. First it is ridiculed, then violently attacked, and finally accepted as self-evident.” Arthur Schopenhauer

  • Thanks to the magnificent work of Dr Hyman medicine that goes to the roots of disease has finally got a solid scientific base. As a dutch GP, having practised for 35 years, as well as a practitioner of natural medicine, I want to thank Dr Hyman for this work. I am happy to have a clear basis now for working with patients using this knowledge that for me is the best way to integrate sometimes necessary symptomatic medicine with the medicine of the true causes of those symptoms.

  • I am currently seeing a fabulous Dr. in southern California – he’s got to be in his 70s – who has been practicing functional medicine for over 40 yrs! My hubby saw him about 30 yrs ago, & after a few unconventional tests (hair, hormonal, metabolic,etc), he knew his problems were resulting from allergies & metal toxins. I, too, am now traveling to see this Dr. a 4 hr drive, one way – because he IS VERY GOOD at what he does & there doesn’t seem to be any reputable functional medical practitioners HERE, in Southern NV. I watch Dr. Oz & saw Dr. Hyman on there a couple times – LOVED HIS segments! I can only hope that MORE Drs begin this type of practice – don’t throw more pills & wildly expensive (&usually unnecessary) tests at me – Mother Nature was our 1st pharmacist, & it seems that she’s making a ‘come back’! ;} I’ve been changing my diet to many more organic veggies & fruits, organic & wild meats/poultry/seafood, as well as tons of spring water. My body is thanking me for it! I plan on using the recipes that Dr. Hyman has given on his site & taking this to the next step, detox & rehydrate as well as drop approx 60#s I’ve gained after 10 surgeries in the past 9 yrs.! I’m a physical wreck & can use all the help I can get – Thx Dr. Hyman!

  • Christy, I am so thankful that I took the time to read this. I recently saw my own doctor and he said the Thryoid gland did not have anything to do with my weight, tiredness or aid in my diabetes, “completely different systems”. So I am looking for a new doctor. If you could kindly provide his name I would be most grateful. I live in southern California so hopefully I won’t need to drive 4 hours.

    Thanks, so much


  • Dr. Hyman,

    I am a clinical nutritionist and I believe in functional medicine and that there is always a cause of conditions in the body. Its a matter of finding it. I was wondering if you believe that there are some conditions that are “idiopathic”? After a client went for a myriad of tests for lower leg swelling the conclusion is idiopathic lymphedema. Should I advise her to keep looking?

    Any input would be appreciated.

    Thanks so much,
    Lisa Goldberg