Frequently Asked Questions
About Functional Diagnostic Nutrition
What is Functional Diagnostic Nutrition (FDN)?
Functional Diagnostic Nutrition (FDN) is a holistic, root-cause approach to health that uses functional lab testing to identify hidden stressors and imbalances in the body — including hormonal
dysregulation, gut dysfunction, immune stress, and nutritional deficiencies. Unlike conventional medicine, FDN looks for the underlying causes of symptoms before they become diagnosable
conditions. As an FDN Practitioner (FDN-P), I am trained to read functional labs through a wellness lens and build personalized protocols using diet, supplements, rest, exercise, stress
reduction, and detoxification support.
What's the difference between a functional nutritionist and a conventional dietitian?
A registered dietitian (RD) works within the conventional healthcare system, focusing on disease management. A functional nutritionist looks beyond symptoms to identify the root cause of
imbalance using advanced lab testing that most conventional providers don't order. I take a whole-person approach — looking at your gut, hormones, sleep, stress, toxicity, and nutrient status as
one interconnected system.
What is an FDN-P and what are they qualified to do?
FDN-P stands for Functional Diagnostic Nutrition Practitioner. FDN-Ps are trained to run and interpret functional lab panels, identify patterns of dysfunction, and build personalized wellness
protocols. I am not a licensed physician and I do not diagnose or treat disease — I support your body's own healing mechanisms and work alongside your medical providers.
What conditions do you work with?
I work with clients experiencing: gut issues (bloating, IBS, SIBO, leaky gut, food sensitivities), hormonal imbalances (adrenal fatigue, thyroid dysfunction, PMS, perimenopause, PCOS), chronic
fatigue, brain fog, chronic inflammation, autoimmune conditions, long COVID and post-viral illness, unexplained weight gain, skin issues connected to gut or hormonal imbalance, and anxiety or
mood issues linked to gut-brain dysfunction. If you've been told your labs are "normal" but you still feel terrible, this is exactly the work I do.
How do I get started?
The first step is a free 15-minute introductory call. We'll talk about where you are with your health, what's working and what isn't, and determine if working together is a good fit. There is no
obligation. Book your free call here.
What does the process look like?
1. Free intro call (15–20 min) — discuss your health history and goals
2. Comprehensive intake questionnaires — completed before your first session
3. Initial 60-minute consultation — review intake, identify patterns, create a plan
4. Functional lab testing — I order labs through a Medical Director program on your behalf
5. Personalized protocol — built around your specific imbalances, not a generic plan
6. Ongoing check-ins — we meet regularly to track progress and adjust as needed
How long will we work together?
3-month programs are ideal for less complex issues. 6-month programs allow time for broader healing — lowering inflammation, gut repair, hormonal rebalancing. 12-month programs are best for
deep-seated chronic conditions. We can continue with ongoing visits after your program ends.
How long before I start feeling better?
Many clients notice meaningful shifts within 4–8 weeks — more energy, better digestion, improved sleep. Deeper healing for chronic conditions typically takes 3–6 months or longer. The body heals
on its own timeline.
Do you work with clients outside of California?
Yes. I serve clients nationwide via Zoom and phone. Lab test kits are mailed directly to your home. Only in-person appointments are limited to those near Mendocino, CA.
Do you work with men, or only women?
I work with both men and women. Hormonal imbalances, gut issues, and chronic inflammation affect everyone. If you're dealing with complex health issues regardless of gender, I'd love to connect.
What kinds of tests do you use?
I use advanced functional lab panels including: GI MAP (comprehensive stool analysis), DUTCH Test (full hormone and adrenal testing), Micronutrient Panel (31 nutrients at the cellular level),
Organic Acids Test (mitochondrial function, neurotransmitter balance), Food Sensitivity Testing, and comprehensive thyroid panels. The specific tests depend on your symptoms, history, and goals.
Why does functional testing matter when my doctor says everything looks normal?
Conventional lab reference ranges are based on population averages — not on what's optimal for vibrant health. There's a significant difference between "not sick enough to diagnose" and "truly
well." I read labs through a functional lens, looking for subclinical patterns that fall within "normal" ranges but still create symptoms.
How much does it cost?
A 1-hour standalone consultation is $200, available in-office, by Zoom, or phone. Longer program pricing is discussed on your free introductory call and varies based on the level of support and
testing needed.
Do you accept insurance?
I do not bill insurance directly. Clients pay out of pocket. I can provide documentation that may support HSA/FSA reimbursement — please check with your plan. Lab testing is typically billed
separately.
What makes your approach different?
I don't use one-size-fits-all programs. Every protocol is completely individualized based on your labs, history, lifestyle, and goals. I draw on training in Functional Diagnostic Nutrition,
Ayurveda, kinesiology, HeartMath, and PEMF. My own healing journey is the foundation of this work — I've been through it, and I know what it takes.
Do you replace my doctor?
No. I am not a physician and I don't diagnose or prescribe. I recommend that all clients maintain the care of a trusted physician. My role complements your medical care by going deeper into
root-cause investigation using nutrition and lifestyle support.
What is the D.R.E.S.S.D. model?
D.R.E.S.S.D. stands for Diet, Rest, Exercise, Stress Reduction, Supplementation, and Detoxification. It's the foundational framework I use with every client — addressing all six pillars
simultaneously to support the body's own healing from the ground up.
Ready to take the next step?
Book your free 15-minute introductory call — no obligation, just a real conversation about your health.
Tennee Gay, FDN-P | (707) 972-5893 | [email protected]
Serving Mendocino, CA and nationwide via Zoom