Functional Testing for Chronic Symptoms: How to Find the Root Cause of Your Symptoms
- Lisa Dack
- Apr 30
- 4 min read
When you're struggling with ongoing symptoms like fatigue, bloating, skin issues, brain fog, or hormonal chaos, it's easy to feel lost. Maybe you've been told your blood tests are "normal", but you know in your gut (literally) that something still isn't right.
This is where functional testing for chronic symptoms can change everything. Testing takes out the guessing and gives us real answers, not just symptom management.
Functional tests are a powerful tool in Nutritional Therapy. They help me understand what’s going on inside your body, so I can create a personalised plan that actually works for you. (Not another generic eat-more-kale plan.)
In this blog, I'm sharing the six key tests I use most often in my clinic and how to know which one might be right for you.
Why Functional Testing for Chronic Symptoms is a Game Changer
It helps uncover the root cause of your symptoms
It identifies imbalances or deficiencies that standard tests might miss
It helps us personalise your nutrition and lifestyle plan more accurately
It can speed up your results by giving us the facts upfront
It provides a strong foundation for sustainable, long-term health change
Which test is right for you?
Choosing the right test depends on your symptoms, history, goals and budget. There is no one-size-fits-all approach. I always work with you to figure out the best starting point.
Here’s a simple guide to my Top 6 Functional Tests:
1. Stool Test (GI Effects by Genova Diagnostics)
A deep dive into your gut health. It looks at:
Inflammation
Digestion and absorption
Microbiome balance (good and bad bacteria, yeast, parasites)
Who it’s for: Anyone with IBS symptoms, bloating, food intolerances, skin issues or a history of antibiotic use.
Why it matters: The gut is linked to everything from skin to hormones to mental health. When you fix the gut, you fix a lot more than digestion.
2. Metabolomix+ (Genova Diagnostics)
A non-invasive urine test that checks your nutritional status including vitamins, minerals, antioxidants, fatty acids, amino acids and gut markers.
Who it’s for: Anyone struggling with mood disorders, fatigue, chronic stress or suspected nutrient deficiencies.
Why it matters: Low energy, poor skin and slow recovery often have a hidden nutrient piece we can fix with precision when we know what’s missing.
3. FDX Ultra (Functional DX)
A full blood health MOT testing over 90 biomarkers including thyroid, blood sugar, liver function, vitamins, minerals, cardiovascular health and hormones.
Who it’s for: Anyone who wants a full-body check, especially if you have lingering chronic symptoms, autoimmune conditions or unexplained fatigue.
Why it matters: This test picks up trends before they become full-blown disease, so you can act earlier and smarter.
4. Rhythm Plus (Genova Diagnostics)
A salivary hormone panel mapping oestrogen, progesterone, testosterone, cortisol, DHEA and melatonin across an entire cycle.
Who it’s for: Premenopausal and perimenopausal women struggling with PMS, irregular periods, anxiety, fertility challenges, hormonal acne or perimenopause symptoms.
Why it matters: Hormones fluctuate daily, not just monthly. This test shows the full picture so we can balance things naturally, safely and effectively.
5. FIT Test (Food Inflammation Test by KBMO)
A blood test that measures delayed food sensitivities (IgG and immune complexes) and gut barrier integrity.
Who it’s for: Anyone with persistent bloating, skin flare-ups, fatigue, brain fog, joint pain or stubborn weight loss despite eating “healthy”.
Why it matters: Food reactions can drive low-grade inflammation that affects energy, mood, digestion and skin. It is hard to spot without proper testing.
6. Thyroid Plus (Genova Diagnostics)
A full thyroid function test checking TSH, T4, T3, reverse T3, thyroid antibodies and thyroid conversion pathways.
Who it’s for: Anyone with fatigue, weight changes, cold intolerance, mood swings, fertility issues, gut problems or a family history of thyroid disorders.
Why it matters: Thyroid health impacts every system in your body. This test shows if your thyroid needs support even when basic GP thyroid tests say "normal".
How I use functional testing with my clients
When we work together, I will listen carefully to your symptoms, your story and your goals. Then we decide if functional testing for chronic symptoms is the right step for you.
Sometimes, we can make great progress without testing. Other times, it is the missing link that unlocks real results.
Functional testing allows me to create a plan based on your body’s needs rather than guesswork, trends or fads.
It is also why my clients often say things like: "For the first time in years, I actually feel like myself again."
Quick Recap: What we might uncover with testing
Gut imbalances and infections
Nutrient deficiencies
Hidden food sensitivities
Hormonal imbalances
Thyroid issues
Blood sugar problems
Early warning signs of chronic disease
Final Thoughts
Functional testing is not just for people who are seriously unwell. It is for anyone who wants to feel their best with clarity, direction and personalised support.
Because if you can measure it, you can manage it.
If you are ready to stop guessing and start getting real answers, book a free call with me today. Together, we will find the root cause, map out a personalised plan, and transform your health from the inside out.
About Lisa
I’m Lisa Dack, a qualified, registered Nutritional Therapist with a special interest in gut health, hormonal imbalances, energy, skin issues and sustainable weight loss. I work one-to-one with individuals to uncover the root causes of their symptoms and create personalised nutrition, lifestyle and wellness plans that fit seamlessly into their lifestyles. Whether you’re struggling with chronic fatigue, digestive issues, or hormonal imbalances, I’m here to guide you toward lasting health transformations. Let’s work together to help you feel your best.
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