The short answer: no blood test reliably identifies "food sensitivities." The IgG panels sold across Canada are recommended against by the Canadian Society of Allergy and Clinical Immunology, and we don't sell them. A structured elimination diet with reintroduction is the gold standard, validated tests exist for lactose and celiac disease, and possible true allergy belongs with a physician. Where gut testing fits: many food reactions are downstream of gut dysfunction — the ecosystem the GI-MAP™ maps.
Food Sensitivity and Intolerance Testing in Canada — What Actually Works
Allergy, Intolerance, "Sensitivity" — Three Different Things
The market is confusing because these words get used interchangeably. They shouldn't be.
Food allergy (IgE-mediated)
A true allergy is an immune reaction driven by IgE antibodies. Symptoms come on fast — usually within minutes to about two hours — and can include hives, swelling, vomiting, wheezing, and in severe cases anaphylaxis — a medical emergency. If this pattern sounds like you or your child, do not self-test: see a physician or allergist for validated skin-prick or allergen-specific IgE testing, interpreted against your history. Health Canada's food allergy resources are a good starting point.
Food intolerance
Intolerances don't involve the immune system — they're usually enzyme or transport problems, with lactose intolerance (not enough lactase) the classic example. Symptoms are dose-dependent and mostly digestive: bloating, gas, cramping, diarrhea. Some intolerances have genuinely validated tests, covered below.
"Food sensitivity"
Here's the honest part: "food sensitivity" has no agreed clinical definition. It's a catch-all for delayed, vague symptoms people connect to food — bloating, brain fog, fatigue, headaches, skin flares, joint aches. Those symptoms are real. But the label's vagueness is what makes it easy to sell tests that don't measure what buyers think they measure.
The Problem With IgG Food Sensitivity Tests
Most products marketed in Canada as a "food sensitivity test" are IgG panels: blood is screened against dozens or hundreds of foods, and higher IgG levels are reported as your "sensitivities."
Current evidence suggests IgG to a food generally reflects exposure — possibly even normal tolerance — not a harmful reaction; you make IgG against the foods you eat often. That's why the Canadian Society of Allergy and Clinical Immunology (CSACI) issued a position statement recommending against IgG food testing for diagnosing food allergy or intolerance, and why the American Academy of Allergy, Asthma & Immunology takes the same position. The practical harms they cite are real: unnecessarily restrictive diets, nutritional gaps, cost, anxiety, and delays in finding the actual cause.
To be plain about it: we do not sell IgG food panels, and if an IgG test is what you're looking for, this is not the site for it. We'd rather explain why than take your money for a report the Canadian allergy society says not to rely on.
What Actually Works
The elimination diet — still the gold standard
An elimination diet with structured reintroduction is the most reliable way to identify a food your body objects to: it measures the endpoint that matters — your actual response. The usual shape is 2–4 weeks removing a short list of suspect foods, then reintroducing them one at a time while tracking symptoms. It costs nothing, but it's easy to do badly — cutting too many foods or staying restricted for months. Do it with a physician or registered dietitian where possible; supervision matters most for children and anyone with a history of disordered eating.
Validated tests for specific intolerances
Some questions have proper tests — usually through your doctor, and often provincially covered when medically indicated:
- Lactose intolerance: a hydrogen breath test or a supervised lactose-free trial — see the NIH's overview of how diagnosis works.
- Celiac disease: blood serology (tTG-IgA) ordered by your physician — crucially, while you are still eating gluten. Going gluten-free before testing can produce a false negative.
- Suspected IgE allergy: skin-prick or specific IgE blood testing, interpreted by an allergist against your history — not as a standalone screen.
Histamine Intolerance: Why There's No Simple Test
Histamine intolerance describes trouble breaking down histamine from food — aged cheese, cured meats, fermented foods, wine — usually attributed to reduced activity of the DAO enzyme made in the gut lining. Symptoms can include flushing, headaches, hives, congestion, and digestive upset shortly after histamine-rich meals.
Here's the honest state of testing: there is no single validated test for histamine intolerance. Serum DAO assays are sold, but the evidence for them is mixed and no major guideline treats them as diagnostic on their own. The practical approach is a time-limited low-histamine elimination trial with structured reintroduction, after your doctor has ruled out look-alike conditions.
What is a "histamine dump"?
A colloquial term, not a diagnosis: a sudden wave of histamine-type symptoms — flushing, racing heart, itching, anxiety — often at night or after a trigger-heavy meal. If that's familiar, a symptom-and-food journal during a low-histamine trial beats any lab panel currently on the market.
Where Gut Testing Honestly Fits
Let's be equally plain about our own test. The GI-MAP™ does not test food sensitivities. It's a qPCR stool test that maps the gut ecosystem your food reactions run through: pathogens, H. pylori with virulence factors, commensal and opportunistic bacteria, fungi, parasites, and intestinal health markers — digestion (pancreatic elastase-1), inflammation (calprotectin), immune activity (secretory IgA), and gut-barrier function (zonulin add-on). Its one food-adjacent marker is anti-gliadin IgA — an immune response to gluten measured in stool, which is not a celiac diagnosis. Our GI-MAP interpretive guide walks through each marker.
Why does that matter? Many "I react to everything" pictures are downstream of gut dysfunction: dysbiosis, H. pylori infection, low pancreatic enzyme output leaving food poorly digested, or a compromised gut barrier. Eliminating twenty "sensitivities" one at a time doesn't help if the real problem is upstream.
Testing the gut first tends to make sense when: you seem to react to many unrelated foods; elimination diets keep failing or the "safe" list keeps shrinking; digestive symptoms dominate; or it all started after a gut infection or food poisoning.
It's the wrong first move when: one food produces a clear, repeatable pattern (run the elimination); the history suggests true IgE allergy (allergist, not a stool test); celiac disease is on the table (physician serology first, while still eating gluten); or you have red flags — blood in the stool, unintended weight loss, anemia, fever, or symptoms that wake you at night. Red flags mean see a physician first, full stop.
If gut-first is the right order for you: the GI-MAP™ Standard is $769.99 CAD and the GI-MAP™ + Zonulin is $869.99 CAD — all-in: kit, free two-way Canada Post shipping, and analysis by CLIA-certified Diagnostic Solutions Laboratory. Kits arrive in 3–5 business days; results land about 7–9 business days after the lab receives your sample (how it works · sample report · HSA eligibility). Review results with a qualified practitioner — an ND or functional/integrative provider — rather than self-interpreting. For a broader look at stool-test options, see our gut health testing guide.
Comparing Your Options in Canada
What each approach measures, what the evidence says, and where Canadians can actually get it.
| Approach | What it measures | Evidence for "food sensitivity" | Typical cost in Canada | Where to get it |
|---|---|---|---|---|
| IgE testing (skin-prick / blood) | True IgE-mediated allergy | Validated — for allergy, not "sensitivity" | Usually provincially covered when physician-ordered | Physician or allergist referral |
| IgG food panels | IgG antibodies to foods (largely exposure/tolerance) | Recommended against by CSACI and AAAAI | Typically several hundred dollars, out of pocket | Widely sold online and in clinics — not here |
| Elimination diet + reintroduction | Your actual response to specific foods | Gold standard when done in a structured, supervised way | Free (dietitian support optional and worthwhile) | At home, ideally with a physician or dietitian |
| Breath tests (e.g. lactose hydrogen) | Malabsorption of specific sugars | Validated for the specific intolerance tested | Often covered when physician-ordered | Hospital GI labs and some private clinics |
| GI-MAP™ qPCR stool test | The gut ecosystem — organisms plus digestion, inflammation and barrier markers (not foods) | Doesn't test foods — finds upstream gut causes; pairs with an elimination diet | $299.99–$869.99 CAD all-in (pricing) | At home — order online, Canada Post both ways |
No approach is "best" in the abstract — they answer different questions. The expensive mistake is buying a test that answers a question you didn't ask.
Honest Answers
Food Sensitivity Testing FAQ
Honestly: a structured elimination diet with careful reintroduction, ideally supervised by a physician or registered dietitian. No blood test — IgG panels included — has been validated to identify food sensitivities, which is why allergy societies recommend against them. Elimination and reintroduction is slower, but it measures the only thing that matters: how your body actually responds to a food.
No — not for diagnosing food sensitivity or intolerance. The Canadian Society of Allergy and Clinical Immunology (CSACI) recommends against IgG food testing because IgG antibodies to foods generally indicate exposure, and possibly normal tolerance, rather than a harmful reaction. The AAAAI takes the same position. We do not sell IgG food panels for this reason.
It depends on the suspect. Lactose intolerance can be assessed with a hydrogen breath test; suspected celiac disease is screened with blood serology ordered by your doctor while you are still eating gluten; and suspected true allergy belongs with a physician or allergist for validated IgE testing. For everything else, a supervised elimination diet with structured reintroduction is the most reliable approach.
There is no single validated test for histamine intolerance. Serum DAO enzyme assays exist, but the evidence for them is mixed, and no major guideline endorses them as diagnostic on their own. The practical approach is a time-limited low-histamine elimination diet with structured reintroduction, ideally guided by a dietitian, after your doctor rules out other causes.
No. The GI-MAP™ is a qPCR stool test — it does not test your reaction to any food. Instead it maps the gut ecosystem those reactions often run through: pathogens, H. pylori, dysbiosis, fungi, parasites, digestion and gut-barrier markers. Its one food-adjacent marker is anti-gliadin IgA, an immune response to gluten in the gut — not a celiac diagnosis. Many people who feel they react to everything have an upstream gut problem rather than dozens of true food sensitivities.
Suspect the Problem Is Upstream, in Your Gut?
We won't sell you a food panel — but if your symptoms point at the gut itself, the GI-MAP™ maps it directly. CAD pricing, free two-way shipping, results in about 2–3 weeks.
Order Your GI-MAP™ Test →All-in CAD pricing · HSA-eligible · CLIA-certified lab · Review results with a qualified practitioner
