Food intolerance testing is a minefield: some tests are genuinely diagnostic, others are heavily marketed but scientifically discredited — and it's easy to spend £150 on a colourful report that tells you nothing reliable. As a CQC-regulated hospital, The Vesey takes an evidence-first approach: this guide explains which tests are worth doing, which to avoid, and the process that actually identifies your trigger foods. No referral needed; GP appointments from £90 and validated blood tests from £32, 7 days a week in Sutton Coldfield.
Intolerance vs Allergy: Why the Difference Matters
A food allergy involves the immune system (IgE antibodies) reacting to a food — symptoms come on within minutes to two hours and can include hives, swelling, vomiting and, rarely, anaphylaxis. Allergies can be tested for reliably with skin-prick or specific IgE blood tests, interpreted alongside your history.
A food intolerance doesn't involve IgE. Symptoms — bloating, wind, cramps, diarrhoea, headaches, fatigue — appear hours later, are dose-dependent, and are unpleasant but not dangerous. Crucially, most intolerances have no single blood test, because most aren't antibody-driven at all: they're usually about enzymes (like lactase), fermentable carbohydrates (FODMAPs), or gut sensitivity.
Getting this distinction right determines which test — if any — is worth your money.
Tests That Are Scientifically Valid
Coeliac serology (tTG-IgA blood test) — the essential first test for anyone with gluten-related symptoms. Coeliac disease affects 1 in 100 people and 70% are undiagnosed. You must be eating gluten regularly for 6 weeks before testing or the result is meaningless.
Lactose intolerance testing — a hydrogen breath test, or a structured 2-week dairy exclusion and reintroduction, both give a clear answer. Lactose intolerance affects roughly 1 in 20 people of North European descent and is far more common in other ethnic groups.
Specific IgE or skin-prick testing — valid where the story suggests true allergy (rapid onset, hives, swelling). Histamine-related and other specialist intolerances are assessed clinically rather than by a single test.
The elimination-and-reintroduction diet — unglamorous, free, and still the diagnostic gold standard for most intolerances: a structured short exclusion of suspected triggers, then systematic reintroduction one food at a time while tracking symptoms. Done with a dietitian, it converts guesswork into a clear, personal answer.
Tests to Be Sceptical Of
IgG food 'sensitivity' panels — the colourful reports testing 100+ foods. IgG antibodies to foods are a normal sign of exposure and tolerance, not intolerance; allergy bodies in the UK, Europe and the US explicitly advise against using IgG results to diagnose food intolerance. They routinely flag dozens of foods, encouraging unnecessarily restrictive diets.
Hair-strand testing, kinesiology and bio-resonance — no plausible mechanism and no evidence; hair contains no information about food reactions. These tests frequently 'detect' intolerances in samples from people with none.
The pattern to notice: any test claiming to screen huge numbers of foods from one sample, without taking a clinical history, is selling certainty it cannot deliver.
How We Approach It at The Vesey
Start with a GP consultation (from £90): the history usually narrows the field dramatically and screens for conditions that masquerade as intolerance — coeliac disease, IBS, inflammatory bowel disease, thyroid dysfunction, and bile acid or pancreatic issues. Blood tests (coeliac serology, inflammatory markers, thyroid, ferritin, B12 — from £32 each) exclude the medical causes first, with results in 24–48 hours.
From there, our dietitians run structured elimination and reintroduction — including low-FODMAP protocols for IBS-type symptoms, which help around 7 in 10 people when properly supervised. Where true allergy is suspected, we arrange validated allergy testing with appropriate specialist input.
The outcome is a short, specific list of foods to limit — not a lifetime ban on 40 foods from a mail-order report. Book online or call 0121 387 3727; open 7 days, 8am–8pm.
Find your real trigger foods — not a 40-food ban list
CQC-regulated · Rated 4.87/5 on Doctify · Open 7 days 8am–8pm · No referral needed
Frequently Asked Questions
What is the most accurate food intolerance test?
For most intolerances, a structured elimination-and-reintroduction diet supervised by a dietitian remains the gold standard. Validated lab tests exist for specific conditions: coeliac serology for gluten, hydrogen breath testing or structured exclusion for lactose, and IgE testing where true allergy is suspected.
Are IgG food intolerance tests worth it?
No — UK, European and American allergy bodies advise against them. IgG antibodies to food indicate normal exposure, not intolerance, so these panels flag long lists of foods you tolerate perfectly well and encourage unnecessary dietary restriction.
Should I get tested for coeliac disease before going gluten-free?
Yes, always. The coeliac blood test (tTG-IgA) only works if you have been eating gluten regularly for about 6 weeks beforehand. Going gluten-free first makes coeliac disease — which needs lifelong strict management — much harder to diagnose.
How much does proper food intolerance assessment cost at The Vesey?
A GP consultation is from £90, individual blood tests (including coeliac serology) from £32, and dietitian appointments are available on site. Most patients get further with one GP visit plus targeted tests than with any mail-order panel. No referral is needed.