Find Out Which FoodsYour Immune System Is Reacting To.
A comprehensive IgG food intolerance blood test that identifies specific foods triggering delayed immune responses — the hidden dietary drivers of inflammation, gut symptoms, and fatigue.
Book Your Food Intolerance Test01
Panel
What's Covered
The EGA Food Intolerance Test is an IgG blood test that measures the levels of antibodies your immune system has produced against a comprehensive panel of 100–200 foods. Reactive foods are flagged and ranked by degree of reactivity, providing a prioritised list to work from.
01Grains and Gluten
Comprehensive screening for wheat, rye, barley, oats, and other gluten-containing foods frequently implicated in delayed immune responses.
02Dairy and Eggs
Assessment of cow's milk, cheese, whey, casein, lactose, and eggs to identify common protein triggers.
03Meat and Fish
A wide range of animal protein sources are tested individually to pinpoint specific sensitivities.
04Fruits and Vegetables
Common produce often missed in elimination protocols, helping to identify unexpected reactive items.
05Nuts, Seeds, and Legumes
Plant-based protein sources and common allergens are assessed for delayed IgG responses.
06Additives and Processed Components
Identification of reactions to common processed food constituents that are difficult to track via a diet diary.
When food particles cross the gut lining into the bloodstream — often in those with 'leaky gut' — the immune system produces IgG antibodies, driving chronic low-grade inflammation.
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Audience
Who It's For
Food intolerance symptoms are often diffuse and delayed, making them difficult to identify through trial and error alone. This test is appropriate for those experiencing:
- Persistent gut symptoms like bloating, gas, or IBS-type presentations not explained by standard testing
- Chronic fatigue that does not resolve with rest, brain fog, or difficulty concentrating
- Skin conditions (eczema, psoriasis, acne) or joint pain that fluctuates with diet
- Headaches, migraines, or mood changes where a dietary trigger is suspected
- A known history of leaky gut or dysbiosis wanting to identify specific dietary contributors
- A desire to reduce chronic low-grade inflammation as part of a longevity strategy
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Deliverable
The EGA Approach: Testing with Clinical Context
The result is not a list of foods to eliminate indefinitely. It is clinical information to guide a structured intervention.
- A report ranking reactive foods by the degree of IgG antibody response
- Clinician review to contextualise findings within your symptom history and clinical picture
- Guidance on a structured elimination and reintroduction protocol — the widely recognised way to confirm triggers
- Identification of dietary inflammatory drivers to support your overall longevity strategy
- Clear next steps for managing gut health and systemic inflammation
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Difference
Food Allergy vs. Food Intolerance
These two terms describe completely different immune responses, and understanding the difference is key to effective management.
Delayed vs. Immediate
Allergies (IgE) cause rapid reactions like hives or swelling. Intolerances (IgG) are delayed, triggering symptoms hours or days later, which is why they are so easy to miss.
Hypothesis Generator
We use IgG testing as a clinical hypothesis generator. It helps identify which foods are most likely to be driving symptoms, guiding a more targeted elimination process.
Chronic Inflammation
In longevity medicine, reducing dietary triggers is vital. Chronic low-grade inflammation is a primary mechanism underlying accelerated biological ageing.
Clinician-Led Interpretation
Elevated IgG antibodies don't always mean clinical intolerance. That's why we include clinician review to help you understand what the data means for your specific health picture.
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Questions
Common Questions
Is IgG food intolerance testing clinically valid?
IgG testing is a functional medicine tool. Several randomised trials show that IgG-guided elimination diets improve IBS symptoms and migraines. However, as healthy individuals can also produce IgG antibodies, at EGA we use it as a hypothesis generator to guide a structured elimination and reintroduction protocol.
What is the difference between this and an NHS allergy test?
NHS allergy testing measures IgE antibodies for immediate allergic reactions. It does not assess delayed IgG-mediated responses. The two tests measure different aspects of immune reactivity and are complementary.
Do I need to avoid any foods before the test?
For best results, do not restrict your diet before the test. The test identifies what your immune system is currently reacting to, which requires recent exposure to those foods.
Will this test diagnose coeliac disease?
No. Coeliac disease requires specific testing for anti-tTG and anti-endomysial IgA antibodies. While this test flags wheat IgG reactivity, it is not a diagnostic tool for coeliac disease.
How do I use the results?
Your clinician will advise on a structured elimination of the highest-reactivity foods for 4–6 weeks, followed by systematic reintroduction to confirm which foods genuinely produce symptoms.
How long do results take?
Your clinician-reviewed report will be available in approximately 1 week from your blood draw.
Do I need to fast before the test?
No fasting is required for this blood test.
What symptoms are associated with food intolerance?
Common symptoms include bloating, gas, IBS-type symptoms, chronic fatigue, brain fog, skin rashes, joint stiffness, and even mood changes or disrupted sleep.
06 · Next Step
Ready to book?
Find Out Which Foods
- 01Step 1: Book online or by phoneNo referral needed. Schedule your blood draw at our London clinic.
- 02Step 2: Attend your blood drawAt EGA Clinic, London. No dietary restriction or fasting is required beforehand.
- 03Step 3: Receive your reportApproximately 1 week later, including your IgG reactivity profile and doctor commentary.
- 04Step 4: Begin your protocolUse the results to start a structured elimination and reintroduction phase guided by clinical advice.