Erin Holt and Rachel Heintz working together at a desk with a MacBook; one standing smiling, the other seated focusing on the computer; office with large window and green plants in the background.

FNA Clinical Vault

Six DUTCH and hormone case reviews from FNA office hours, led by Rachel — FNA's lead clinical mentor. Watch how FNA students work through real patient cases, from lab results to clinical plan.

Case 01 · DUTCH · PCOS · Mitochondria

The Mitochondrial Missing Link in PCOS

27-year-old · PCOS, irregular cycles, acne, anxiety, severe irritability, breast tenderness, orthorexia history


A student brings her first DUTCH case — a patient she hasn't yet met. The results raise immediate questions: mismatched cortisol dials, low testosterone relative to DHEA, estrogen dominance with low progesterone, and glutathione below range. Rachel works through what's driving each marker and how to prioritize care without overwhelming a patient who already has a complicated relationship with supplements.

What Rachel covers

  • Mismatched free vs. metabolized cortisol — what it means and why you can't answer the "why" without a full thyroid panel first

  • DHEA → testosterone conversion happens in the mitochondria — and why that changes your treatment priority for PCOS

  • Reading estrogen + progesterone together (not just individual markers) to explain this patient's irritability, breast tenderness, and cramps

  • Vitex dosing, timing, and the 750mg formulation Rachel prefers

  • NAC as a double-whammy: glutathione support and estrogen metabolism pathway support at the same time

  • Why Rachel wouldn't use MACA for this patient despite low testosterone

Case 02 · DUTCH · GI Map · SIBO · Perimenopause

When SIBO Makes Everything Else Impossible to Treat

46-year-old · Endometriosis, perimenopause, on thyroid meds + HRT, constipation + loose stools, became intolerant to supplements


The student had been working this case for months — building up the gut, clear plan in place — until the patient stopped tolerating every supplement she was put on. The SIBO test wasn't in the original plan. But the supplement intolerance turned out to be the most important clinical clue. Rachel explains why the DUTCH results have to wait, and how to sequence care when multiple systems are dysregulated at once.

What Rachel covers

  • Why supplement intolerance — not GI symptoms — was the flag pointing to SIBO

  • Reading SIBO breath test results when they're incomplete, and when to treat anyway

  • Candibactin AR + BR: Rachel's dosing protocol and why she chose it over berberine here

  • How to explain to a patient why her hormone results have to wait

  • The difference between always-intolerant vs. became-intolerant — and what that tells you about biofilms

  • Amino detox approach for patients who can't tolerate standard interventions

Case 03 · DUTCH · Thyroid · T3 Conversion

T4 Is Fine. T3 Is Not. Here's Why That Matters.

58-year-old · Perimenopause, anxiety, dry skin, nighttime waking, hypothyroid pattern — wants to avoid medication


This patient's T4 is optimal. Her T3 is low and her TSH is elevated. She's producing plenty of thyroid hormone — she's just not converting it. Rachel walks through the full thyroid panel, explains exactly where the breakdown is, and models how to have an honest conversation with a patient who wants to avoid medication without dismissing that option.

What Rachel covers

  • How to read T4, free T4, total T3, and free T3 together — and what elevated TSH is actually telling you

  • Why T4→T3 under-conversion is a liver and gut problem, not a thyroid production problem

  • The medication conversation: what T4-only meds do and don't fix, and how to present it without being prescriptive

  • Selenium (two Brazil nuts), zinc, and iodine — what to prioritize and when to test before supplementing iodine

  • ZRT urinary iodine test: when to use it and what it tells you that topical assessment doesn't

  • Thyroid antibodies: when a mild elevation warrants attention and when treating root causes (liver + gut) brings them down anyway

Case 04 · DUTCH · Birth Control · Estrogen Dominance

Reading DUTCH When a Patient Is on the Pill

28-year-old · PCOS, on hormonal birth control for 8 years, weight gain, insulin resistance, low energy, thinning hair


When someone is on hormonal birth control, their DUTCH results should show suppressed hormones. This patient's don't — her estrogen is robust despite being on the pill. Rachel explains why that's happening, what it tells you about the underlying clinical picture, and how to approach a case where the labs don't match what you'd expect from the chart.

What Rachel covers

  • What DUTCH should look like on hormonal birth control — and what it means when it doesn't

  • Why the estrogen is still showing up and what that tells you about what the pill has (and hasn't) been doing

  • Reading estrogen metabolite ratios when a marker is flagged — when to be concerned vs. when the ratio is proportionate

  • DIM and calcium D-glucarate: what they're doing mechanistically and when to reach for each

  • B6 and B12 deficiencies on DUTCH — when to investigate absorption rather than assume it's the pill or diet

  • The quinolinate marker: what it signals, when it matters clinically, and how to explain it without alarming a patient

Case 05 · DUTCH · High Cortisol · AdrenalReading DUTCH When a Patient Is on the Pill

High Cortisol, DGL, and the Body That Won't Slow Down

43-year-old · Anxiety, low energy, weight loss resistance, alternating bowel movements, elevated cortisol + cortisol awakening response


A naturopath recommended DGL for this patient's GI symptoms, but the practitioner wasn't sure if licorice root was safe with elevated cortisol. Rachel answers that clearly, then works through the full picture: a cortisol deactivation pattern that tells a specific story about what this patient's body is doing, and how to communicate that to a patient in a way that actually changes her behavior.

What Rachel covers

  • DGL vs. licorice root — why they're different and why DGL is appropriate even with high cortisol

  • What it means when the body is rapidly deactivating cortisol into cortisone — and how Rachel explains this to patients

  • Phosphatidylserine and melatonin timing for a high-cortisol, poor-sleep pattern

  • Low progesterone + estrogen dominance in the context of adrenal dysregulation

  • When DHEA and testosterone dials don't line up and what the mitochondrial connection looks like in practice

  • Managing care when a patient has multiple practitioners — and how to have that conversation

Case 06 · DUTCH · GI Map · Complex Autoimmune

When the Labs Look "Unremarkable" But Something Is Clearly Wrong

41-year-old · Celiac, gastroparesis, fibromyalgia, RA, Raynaud's, pelvic floor dysfunction, on birth control, wants to conceive


Five autoimmune diagnoses. Daily enemas to feel empty after a bowel movement. A GI map that isn't — as the practitioner says — "screaming anything." This case is a lesson in knowing when to look past the labs. Rachel navigates the structural, nervous system, and hormonal pieces, and models the birth control + preconception conversation in a way that's honest, empowering, and practical.

What Rachel covers

  • Reading a GI map when markers are present but not dramatic — and why clinical context changes how you respond

  • Migrating motor complex, prokinetics, and why grazing + gastroparesis + pelvic floor dysfunction is a triple problem

  • Pelvic floor PT, ileocecal valve massage, and when to suggest a colonic for ileocecal valve stimulation

  • When daily enemas might signal something worth addressing beyond the physical — and how to raise that carefully

  • The birth control + preconception conversation: the 100-day egg maturation window, the fifth vital sign, and how to frame it as an invitation

  • Mismatched cortisol dials with liver burden and birth control — and when a thyroid panel is worth adding

Rachel Heintz smiling woman with brown hair and hazel eyes, wearing a dark top, in a well-lit indoor setting.

Your Guide

Rachel Heintz, MS, RDN, IFMCP, FHP-C

Lead Clinical Mentor · Funk'tional Nutrition Academy

Rachel is the lead clinical mentor inside FNA - the practitioner students bring their most complex cases to. She has deep clinical experience in functional nutrition with a specialization in DUTCH interpretation, hormone health, and the kind of multi-system cases that don't fit neatly into any protocol.

The sessions in this vault are pulled directly from Rachel's monthly office hours with FNA students. What you're watching is Rachel working a real case in real time, thinking out loud, asking the questions that need to be asked, and modeling the kind of clinical reasoning that takes years to develop on your own.

Inside FNA, practitioners have access to these sessions every month with their own patient cases. This is a window into that experience.

When You Enroll in FNA

You get this every month — with your own cases.

The sessions you just watched are part of what every enrolled FNA practitioner has access to. Monthly live office hours with Rachel, where you submit your real patient cases and work through them together.

Not a recorded Q&A. Not a static curriculum. A live session where Rachel looks at your actual labs, asks the questions you didn't think to ask, and works through the clinical reasoning with you in real time.

📅 Monthly Live Office Hours Regular case review sessions with Rachel throughout your enrollment
🔬 Bring Your Real Cases Submit your actual patients and get Rachel's eyes on your labs and clinical questions
🎓 Full FNA Curriculum Comprehensive functional medicine training with Erin Holt, built for real-world practitioners
🤝 A Cohort of Practitioners Learn alongside practitioners who bring the same level of seriousness to their work