Food Intolerance Testing
View All TestsWhat Is Food Intolerance?
Food intolerance refers to difficulty digesting certain foods, leading to symptoms such as bloating, abdominal discomfort, and changes in bowel habits. Unlike a food allergy, which involves an IgE-mediated immune response, food intolerances generally involve non-immune mechanisms — for example, an enzyme deficiency such as lactase deficiency in lactose intolerance.
Common food intolerances include lactose intolerance, gluten sensitivity (distinct from coeliac disease), and histamine intolerance. Symptoms can sometimes overlap with those of IgE-mediated food allergies, making it helpful to distinguish between the two through appropriate testing.
Our clinic offers blood tests that may help clarify whether your symptoms relate to an immune-mediated allergy or a genetic predisposition such as lactose intolerance. Results are provided directly to you to share with your GP or dietitian for interpretation and guidance.
Food Allergy vs Food Intolerance
| Feature | Food Allergy | Food Intolerance |
|---|---|---|
| Immune involvement | IgE-mediated immune response | Generally non-immune (enzyme or chemical) |
| Onset | Usually within minutes to 2 hours | May take hours to develop |
| Severity | Can be severe (anaphylaxis possible) | Uncomfortable but generally not life-threatening |
| Common symptoms | Hives, swelling, breathing difficulty | Bloating, gas, abdominal discomfort |
| Testing | Specific IgE blood test | Genetic testing, breath tests, elimination diets |
If you are unsure whether your symptoms may relate to an allergy or an intolerance, you may find our article on dairy allergy vs lactose intolerance helpful.
How Testing Works
Choose Your Test
Select from our range of allergy blood tests and book a convenient time at our South Kensington clinic. No GP referral needed.
Nurse Blood Draw
A qualified nurse takes a small blood sample at our clinic. The appointment is quick and straightforward.
Get Your Results
Results are sent directly to you, typically within a few working days. Share them with your GP or specialist to guide your next steps.
Recommended Tests for Food Intolerance
ALEX² Allergy Test (Venous)
Allergy Profile 3 (Food)
Gluten Sensitivity Evaluation
Gluten Sensitivity Profile
Lactose Intolerance Gene
Total IgE
Wheat Components
Why Choose a Diagnostic-Only Clinic?
Unlike clinics that provide both testing and treatment, our nurse-led service focuses solely on accurate diagnostic testing. Because we don't offer treatments or prescriptions, there is no commercial incentive to recommend unnecessary tests — just honest, impartial results you can trust.
Nurse-Led & Impartial
Our qualified nurses collect your sample — we don't prescribe, treat, or have any reason to upsell.
Results You Own
Your results are sent directly to you. Take them to your GP or a specialist to discuss what's best for your situation.
You Stay in Control
Understand your allergy profile, then decide with your healthcare professional what steps to take next.
Related Reading
Frequently Asked Questions
Can a blood test detect food intolerance?
Specific blood tests can help identify certain types of food sensitivity. Our Lactose Intolerance Gene test identifies genetic predisposition, while our Gluten Sensitivity Profile evaluates markers associated with gluten-related conditions. Standard IgE tests detect food allergies rather than intolerances.
What is the difference between food intolerance and coeliac disease?
Coeliac disease is an autoimmune condition triggered by gluten, involving specific antibodies and intestinal damage. Non-coeliac gluten sensitivity may produce similar symptoms without the autoimmune component. Both can be investigated through blood testing.
Do I need to be eating the food before testing?
For genetic tests such as the Lactose Intolerance Gene test, current diet does not affect results. For gluten-related testing, consuming gluten beforehand may be relevant — your GP can advise on preparation.
Do I need a GP referral for allergy testing?
No. You can book directly with our clinic without a GP referral. Simply choose your test and select a convenient appointment time. If you're unsure which test is right for your symptoms, our team can help guide your selection.
Do I need to stop taking antihistamines before a blood test?
No. Unlike skin prick testing, IgE blood tests are not affected by antihistamines or other allergy medications. You can continue taking your regular medications before your appointment.
What should I do with my results?
As a diagnostic-only clinic, we provide results directly to you. We recommend sharing them with your GP, gastroenterologist, or dietitian for interpretation and dietary guidance.
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