The Pioneers of Functional Testing & Advanced Diagnostics.
Here at Functional Diagnostic Nutrition® (FDN), we are a team of pioneers, teachers & wellness advocates dedicated to educating & inspiring better health across the world.
The Pioneers of Functional Testing & Advanced Diagnostics.
Here at Functional Diagnostic Nutrition® (FDN), we are a team of pioneers, teachers & wellness advocates dedicated to educating & inspiring better health across the world.

Functional Testing & Advanced Diagnostics

Here at Functional Diagnostic Nutrition® (FDN), we are a team of pioneers, teachers & wellness advocates dedicated to educating & inspiring better health across the world.

Through the FDN Certification Course, we teach people cutting-edge methods of evaluating functional lab results so they can heal themselves & grow robust wellness practices doing what they love.

We also offer advanced training courses on specific topics ranging from stress & hormones to thyroid function, and actively participate as leaders in the functional health community at worldwide conferences & events.

“At FDN, our mission is to educate as many people as possible about how to get well & stay well naturally, so they in turn can empower others to live healthier lives.” 

Reed Davis, FDN Founder

Functional Testing Education

The FDN Mission

In staying true to our mission, we have kept our courses open to anyone with a desire to learn. 

Yes, this means there are no prerequisites!

The FDN certification course & advanced courses are well-suited for:

  • Anyone wanting to launch a new career as a health coach or practitioner
  • Health Coaches looking to offer functional testing to their clients 
  • Medical Professionals looking to get better results for their clients
  • Anyone interested in healing themselves & helping others

A Story of Trailblazing | The FDN Journey

Over 20 years ago, FDN Founder, Reed Davis, recognized that most patients with chronic conditions were caught in a frustrating cycle of trialand-error, desperately searching for answers, but never finding the lasting results they were after. 

He watched as patients went from practitioner to practitioner, only to be told “everything looks normal”, or to be convinced of yet another unsuccessful supplement protocol, fitness program or healing modality. Reed refused to be just another practitioner in this endless cycle. So he committed to being the last person his clients saw on their quest for answers & better health.

Over the next ten years, while working at a wellness center in Southern California, Reed reviewed thousands of functional lab reports for thousands of people. He credits great mentors but also his own careful observations about who was getting better, and who was not

Reed Davis
Reed Davis FDN

The patterns he recognized began to reveal an entire constellation of “healing opportunities”, giving way to what is now Functional Diagnostic Nutrition® (FDN). 

Wanting to put this newfound knowledge to good use, Reed developed the D.R.E.S.S. for Health Success® – a simple but powerful framework for creating all-natural, drug-free protocols that empower people to take control of their own health. 

Over time, thought leaders in the alternative medicine & functional health communities noticed Reed’s work and asked him to share his methodology. Wanting to help as many people as possible, he humbly offered a workshop to about 25 people in 2008. And, as Reed likes to say…“the rest is history”.

Today, FDN has trained over 4,000 practitioners in 50+ countries, and helped over 10,000 people get well & stay well naturally. Reed is known as one of the most successful and experienced clinicians in the world, having provided functional assessments to over 10,000 clients. 

At FDN, we believe in…

  • heal the human body

    The Human Body

    We believe the human body was designed to thrive. Given the right support & healthy environmental conditions, we believe the human body is capable of healing from just about anything. When we work *with* the body, instead of against the body, we help restore balance & harmony.

  • data driven health

    Data-Driven Health

    We believe knowledge is power. Understanding how to gather & analyze data is one of the most important factors in achieving optimal wellness. Functional diagnostic testing & evaluation is the key to identifying biochemical, nutrient, gut & hormonal imbalances. Understanding how to analyze test results is crucial to helping people recover & build health.

  • Bio-Individuality


    We believe in highly-customized protocols. There is no “one-size-fits-all” approach to health & wellness. What helps one person recover & heal may aggravate symptoms in another. While the FDN methodology works for everyone, the protocols that result from this methodology are highly-personalized & unique to each individual.

  • functional health pioneering


    We believe in pushing past the status quo. As pioneers in the functional health community, we believe in always looking for better, more efficient ways to serve our community. We are lifelong learners, and encourage our students to remain curious as they move forward as industry trailblazers themselves.

Common Questions About Functional Testing

Yes! Our graduates are able to order 60+ functional lab tests for themselves and/or their clients through our Medical Director Program. This allows unlicensed individuals to order testing, and includes a 30-minute consultation to review lab results each time an order is placed. 

FDN Practitioners are health detectives – trained in investigating underlying causes & conditions, and using evidence-based protocols to restore function & vitality. They understand how to select the right functional tests, and exactly what clues to look for when analyzing the lab results. 

While functional testing can help anyone build better health, it’s important to understand that FDN Practitioners do not diagnose or treat disease. Instead, the FDN methodology teaches people to identify healing opportunities & eliminate contributors to Metabolic Chaos®. This means that FDN Practitioners are well-suited to support just about anyone in restoring function & harmony throughout the body. 


Snag the 3-Step Guide to Getting Better Results with Functional Testing & Diagnostics.

Take a closer look at how FDN Practitioners use the FDN methodology to better serve their clients, with our 3-step guide to better results.

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The Gold Standard in

Functional Testing Training

As pioneers in the functional health community, we are well-known & trusted by top-tier institutions & thought leaders across the world. 

The FDN Certification Course is an accredited training program and graduates are eligible for the following:

  • American Natural Wellness Coaches Board (ANWCB) exam
  • American Association of Natural Wellness Coaches (AANWC) exam
  • American Association of Drugless Practitioners (AADP) exam
  • Guardian Ecclesiastical Medical Association (GEMA) licensure 
  • American Natural Wellness Practitioners Board (ANWPB) exam (for those with a degree in naturopathy)



A Functional Testing Trailblazer

Whether you’re looking to heal yourself, get better results with clients, or launch a new career, becoming an FDN Practitioner will empower you with the practical knowledge you need to transform lives & build a robust wellness practice.