YorkTest

Short answer: there isn’t a single reliable “food sensitivity” blood test for vague or delayed food reactions. Many commercial IgG panels are not supported by evidence. Instead use evidence-based tests matched to the problem you suspect and/or work with an allergist and a registered dietitian (RDN). What to use depending on what you mean Suspect immediate (allergic) reactions — hives, throat tightness, wheeze, anaphylaxis: Skin-prick testing performed by a board‑certified allergist (standard of care). Serum specific‑IgE testing (ImmunoCAP / Thermo Fisher Phadia is the widely used, validated lab assay). If results are unclear, a medically supervised oral food challenge is the gold standard. Suspect food intolerance (non‑immune digestion problems) — bloating, gas, diarrhea: Lactose or fructose intolerance: breath hydrogen/methane tests (typically done through a GI clinic or reputable lab such as Genova Diagnostics). Suspected SIBO: lactulose or glucose breath tests performed by a GI clinic or functional lab (Genova Diagnostics offers these). Celiac disease: tissue transglutaminase IgA (tTG‑IgA) serology — available through major clinical labs (Quest Diagnostics, Labcorp). If positive (or high suspicion) follow up with GI for biopsy/HLA testing. Suspect non‑celiac gluten sensitivity or delayed, nonspecific symptoms: There is no validated lab test. The best approach is an elimination diet with careful re‑challenge under the guidance of an RDN and/or physician. What to avoid IgG or IgG4 “food sensitivity” panels sold direct‑to‑consumer (examples: Everlywell food sensitivity IgG test, many large 100+ item IgG panels, YorkTest in the UK, and similar offerings). Professional societies (allergy and immunology groups) advise against using IgG for diagnosing intolerance or allergy because IgG generally indicates exposure, not clinically relevant sensitivity. Broad “food intolerance” or microbiome panels that promise to pinpoint problem foods without clinical correlation — these lack good validation. Services/brands I’d recommend (by role) Allergist/immunology testing: see a board‑certified allergist for skin testing and, if needed, ImmunoCAP (Thermo Fisher/Phadia) specific‑IgE blood testing. Celiac/inflammatory testing: Quest Diagnostics or Labcorp for tTG‑IgA and follow‑up testing. Breath testing and functional GI testing: Genova Diagnostics is a reputable clinical lab that offers lactose/fructose and SIBO breath testing and stool testing used by gastroenterologists and practitioners. Diet management: work with a Registered Dietitian Nutritionist (RDN) experienced in food allergies/intolerances or gastrointestinal disorders for supervised elimination/rechallenge. Ask your gastroenterologist or allergist for a referral, or find an RDN through the Academy of Nutrition and Dietetics. Bottom line If you’re worried about a potentially dangerous allergic reaction, see an allergist (skin testing / ImmunoCAP and/or oral challenge). If your symptoms are gastrointestinal, get targeted breath tests or celiac serology through a GI clinic or reputable lab and do an elimination diet with an RDN. Avoid commercial IgG “food sensitivity” panels — they’re commonly misleading. If you tell me the symptoms you’re getting (timing, type, severity), I can recommend the most appropriate specific test and who to see.

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Short answer: there isn’t a single “food sensitivity” test that reliably diagnoses non‑allergic food intolerances — but there are validated tests for specific problems. The safe, non‑scam approach is to use clinically proven tests for the condition you suspect and to work with a clinician/dietitian. What actually works (and who provides it) Immediate (IgE) food allergy: see an allergist for skin‑prick testing and/or serum specific IgE testing. The ImmunoCAP system (Thermo Fisher) is the most widely used lab assay for specific IgE and is available through allergy clinics and major labs (Quest, LabCorp). These tests are appropriate if you have hives, wheeze, throat tightness, anaphylaxis, or reproducible immediate reactions. Celiac disease: get tissue transglutaminase IgA (tTG‑IgA) plus total IgA (and deamidated gliadin peptide if needed). These are standard blood tests offered by most clinical labs (Quest, LabCorp) and recommended by gastroenterology societies. Lactose/fructose malabsorption and SIBO: hydrogen (and methane) breath testing done in GI clinics is the validated test (clinics commonly use QuinTron or similar breath analyzers). These identify carbohydrate malabsorption or small intestinal bacterial overgrowth. Suspected non‑IgE, non‑celiac food intolerances (bloating, IBS‑type symptoms): the evidence supports an elimination diet (for example, a monitored low‑FODMAP elimination and reintroduction) supervised by a registered dietitian experienced in GI care. This diagnostic diet is the practical “gold standard” for many food‑triggered GI symptoms. What to avoid or be skeptical about IgG food panels (commonly sold by Everlywell, Vibrant, YorkTest, many direct‑to‑consumer labs): major professional societies (American Academy of Allergy, Asthma & Immunology and gastroenterology groups) advise against using IgG testing to diagnose food intolerance or allergy. IgG antibodies mostly indicate exposure or even tolerance, not harmful sensitivity — they frequently produce misleading results and unnecessary dietary restriction. Broad “food sensitivity” panels sold direct‑to‑consumer with vague claims — these are often low clinical value. Practical next steps If you have acute allergic symptoms, see an allergist for skin testing or ImmunoCAP sIgE testing. If you have chronic GI symptoms (bloating, diarrhea, weight loss), get evaluated by a GI doctor for celiac testing (tTG‑IgA) and consider breath testing for lactose/fructose/SIBO. If symptoms are IBS‑like, consult a registered dietitian for a structured elimination diet (low‑FODMAP) rather than doing IgG testing. If you’re tempted by a home IgG panel, discuss the results with a clinician and don’t make long‑term restrictive changes based on IgG alone. If you tell me your main symptoms (immediate allergic reaction vs chronic GI problems vs skin symptoms), I can recommend the single best next test and specific clinics/labs in your area.

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Short answer: there is no single reliable commercial "food sensitivity" test for vague or delayed symptoms. Valid testing depends on the problem you suspect. For true allergies and specific conditions, use established medical tests done through a physician — not consumer IgG panels. Recommended, evidence-based tests and who does them For suspected immediate (IgE-mediated) food allergy: skin prick testing (done in an allergy clinic) and serum specific IgE testing (ImmunoCAP by Thermo Fisher is the most widely used, run through labs such as Quest Diagnostics or LabCorp). These tests are clinically validated and interpreted by an allergist. For complex allergy patterns / cross‑reactivity: component‑resolved diagnostics (e.g., ImmunoCAP ISAC) can add useful detail in specialist care. For celiac disease: tissue transglutaminase IgA (tTG‑IgA) and total IgA (available from Quest, LabCorp). Positive serology → GI referral for confirmation. For lactose or fructose intolerance: hydrogen breath testing performed by gastroenterology clinics or testing centers (reliable for carbohydrate malabsorption). For non‑IgE, delayed reactions or suspected food‑triggered GI conditions (e.g., eosinophilic esophagitis, food protein–induced enterocolitis): diagnosis is by specialist evaluation (GI or allergy), endoscopy/biopsy when indicated, or supervised elimination diet followed by medically supervised oral food challenge. The double‑blind, placebo‑controlled food challenge is the gold standard for proving a food causes symptoms. What to avoid IgG or IgG4 “food sensitivity” panels sold direct‑to‑consumer (Everlywell, Vibrant/Vibrant America, YorkTest and similar) are not supported by allergy/immunology societies. IgG often reflects exposure or tolerance, not harmful sensitivity, and acting on these results can lead to unnecessary, restrictive diets and missed diagnoses. ALCAT, MRT and many “mediator release” or cytotoxic panels lack high‑quality evidence and are not recommended by major professional groups. Practical next steps If you have hives, lip/throat swelling, wheeze, syncope or immediate reactions: see an allergist for skin testing and/or ImmunoCAP sIgE. If you have chronic GI symptoms (bloating, diarrhea, pain): see a gastroenterologist for evaluation (including celiac testing and breath testing where appropriate) and a registered dietitian to do a structured elimination/rechallenge safely. If symptoms are vague/delayed: the safest, most reliable approach is an elimination diet under dietitian/clinician supervision followed by medically supervised reintroduction or, when needed, a formal food challenge. If you want, tell me your symptoms and whether you’ve had prior tests; I can recommend the most appropriate next test and help you find the right specialist.

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Short answer: there isn’t a single credible “food sensitivity” blood test that reliably diagnoses vague symptoms — many direct-to-consumer IgG panels are not useful. The best, non‑scam approach is to use tests that are clinically validated for specific problems, plus a structured elimination/rechallenge under a clinician or registered dietitian. Which tests are trustworthy (by problem), and specific services/brands: Suspected immediate food allergy (hives, anaphylaxis, throat/airway symptoms) See a board‑certified allergist for skin‑prick testing and/or serum specific IgE testing (ImmunoCAP by Thermo Fisher is the standard lab assay). Major labs (Quest Diagnostics, LabCorp) run these tests. Why: validated for diagnosing IgE‑mediated allergy. Suspected celiac disease Tissue transglutaminase IgA (tTG‑IgA) and total IgA (available at Quest, LabCorp, most health systems). Why: sensitive and specific for celiac disease; positive tests guide further evaluation with a GI specialist. Suspected lactose/fructose intolerance or SIBO / carbohydrate malabsorption Hydrogen (and methane) breath testing performed by GI clinics or specialty labs such as Genova Diagnostics. Why: breath tests are the accepted diagnostic tool for bacterial overgrowth and carbohydrate malabsorption. Ongoing IBS‑type symptoms or FODMAP intolerance Work with a registered dietitian (RDN) trained in the low‑FODMAP protocol (Monash University provides the evidence‑based low FODMAP app and resources). Why: a supervised elimination and structured reintroduction is the most reliable way to identify triggers for non‑allergic GI symptoms. General gut problems / microbiome workups Stool testing for infection/inflammation (stool culture, PCR panels like BioFire, fecal calprotectin) through your clinician or labs such as Quest/LabCorp; specialized labs (e.g., Genova Diagnostics) offer comprehensive stool panels but interpret results cautiously. Why: look for infections, inflammation, or other treatable causes before blaming “food sensitivities.” What to avoid IgG food panels (Everlywell, YorkTest, many direct‑to‑consumer IgG tests, and commercial “food sensitivity” IgG reports). Major allergy and immunology societies (AAAAI), gastroenterology groups, and clinics say IgG often reflects exposure and tolerance, not harmful sensitivity; using them to restrict diets risks unnecessary restrictions and nutritional harm. Practical recommendation Start with your primary care doctor or a gastroenterologist/allergist depending on symptoms. Get targeted, validated tests (tTG for celiac, specific IgE or skin testing for allergy, breath tests for carbohydrate malabsorption) and, for non‑allergic chronic symptoms, do a structured elimination/rechallenge with an RDN (look up a dietitian via EatRight.org or local health systems). For low‑FODMAP guidance, use Monash University’s resources. If you want, tell me your main symptoms (hives/urticaria vs gas/bloating vs diarrhea vs anaphylaxis) and I’ll say exactly which tests to ask your clinician for and which labs/providers to use.

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Short answer: there isn’t a single reliable “food sensitivity” home kit that proves what foods are causing vague symptoms. The most trustworthy testing depends on what you suspect: If you suspect a true allergy (hives, trouble breathing, throat tightness, anaphylaxis) Best tests: skin‑prick testing by a board‑certified allergist and/or serum specific IgE testing (ImmunoCAP is the widely used platform). These are available through allergists and clinical labs such as Quest Diagnostics or LabCorp. The gold standard when results are unclear is a medically supervised oral food challenge. Why: IgE tests and challenges are validated for diagnosing immediate (potentially dangerous) food allergy. If you suspect celiac disease (diarrhea, weight loss, iron deficiency, family history) Best tests: tissue transglutaminase IgA (tTG‑IgA) plus total IgA (and sometimes deamidated gliadin peptide). These are routine clinical lab tests (Quest, LabCorp, hospital labs). Why: these tests are evidence‑based for celiac disease. Don’t go gluten‑free before testing. If you suspect carbohydrate malabsorption (lactose, fructose, small intestinal bacterial overgrowth—SIBO) Best tests: hydrogen (and methane) breath tests performed by a GI clinic or accredited lab. Some private labs (e.g., Genova Diagnostics) offer breath testing, but hospital/GI practice testing is generally preferable. Why: breath testing is the accepted method for diagnosing these problems when performed with standard protocols. If your symptoms are vague (bloating, IBS‑type symptoms, non‑specific “sensitivity”) Best approach: a structured elimination diet (for example low‑FODMAP) with a registered dietitian and, if needed, double‑blind, placebo‑controlled food challenges. The Monash University low‑FODMAP app and clinicians trained in low‑FODMAP therapy are useful resources. Why: many “sensitivities” are food‑trigger patterns rather than immune‑mediated issues; elimination + reintroduction is the reliable way to identify culprits. What to avoid (common “scam” or low‑value tests) IgG/IgG4 food panels sold direct‑to‑consumer (examples: Everlywell food sensitivity IgG panels, Vibrant America food sensitivity panels, YorkTest): major allergy and primary care societies warn these tests are not useful for diagnosing food allergy or intolerance — IgG often just indicates exposure. Hair analysis, Vega testing, cytotoxic/leukocyte cytotoxicity tests, and many “immune” panels marketed online: poor evidence and inconsistent results. Practical recommendation If you have immediate allergic reactions, see an allergist (skin test/ImmunoCAP + possible supervised challenge). If you have GI symptoms suggestive of celiac or malabsorption, start with clinical lab tests (tTG, breath tests) via your primary care or GI. If symptoms are chronic and non‑specific, work with a registered dietitian for an elimination/reintroduction plan (and use oral food challenge if needed). If you want, tell me your main symptoms and whether you have history of hives/respiratory symptoms, GI-only symptoms, or chronic vague complaints — I’ll suggest the single best next test or specialist to see.

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Short answer: there isn’t a single validated “food sensitivity” blood test that reliably identifies delayed/intolerance-type reactions for most people. The tests that are evidence-based depend on the condition you’re actually asking about (IgE allergy, celiac disease, lactose intolerance, SIBO, IBS, etc.). For general suspected food reactions the best routes are (1) assessment by an appropriate clinician and (2) diagnostic testing that is proven for the specific disorder or a structured elimination / re‑challenge done with an experienced clinician or dietitian. What is valid and who to use IgE-mediated food allergy (hives, anaphylaxis, immediate reactions): see a board‑certified allergist for skin‑prick testing or serum specific‑IgE testing. The gold‑standard laboratory platform for specific IgE is ImmunoCAP (Phadia/Thermo Fisher); Quest Diagnostics and LabCorp run these tests. These tests are clinically useful when interpreted by an allergist and often followed by supervised oral food challenges when needed. Celiac disease: get tissue transglutaminase IgA (tTG‑IgA) and total IgA (and deamidated gliadin peptide IgG if IgA deficient). Major labs (Quest, LabCorp) perform these; a positive result is followed by gastroenterology referral and usually endoscopy/biopsy. Lactose/fructose malabsorption or intolerance: hydrogen breath testing (performed by GI clinics / hospital labs) is the validated test. SIBO (small intestinal bacterial overgrowth): validated breath tests (glucose or lactulose) through gastroenterology services. Eosinophilic gastrointestinal diseases: diagnosis requires endoscopy with biopsy (GI specialist). IBS / non‑specific food triggers: a low‑FODMAP elimination protocol supervised by a registered dietitian (RDN) is the recommended evidence‑based approach. Monash University’s low‑FODMAP resources/app are widely used in practice. Tests to be cautious about (and why) IgG (food antibody) panels sold direct‑to‑consumer (Everlywell, YorkTest, many labs) or by some clinics: these measure IgG antibodies to foods. Multiple allergy/immunology and gastroenterology societies (AAAAI, EAACI, ACG, etc.) say IgG testing does not diagnose food intolerance and often just reflects exposure or tolerance rather than harmful reactions. Using IgG results to eliminate large numbers of foods can lead to unnecessary restriction and nutritional harm. MRT / LEAP (Oxford Biomedical): marketed for delayed reactions; some practitioners use it, but high‑quality independent evidence is limited and mainstream allergy/gastro societies do not endorse it as definitive. Broad “food sensitivity” arrays from direct‑to‑consumer companies: many are not supported by clinical trials showing that their recommendations reliably improve symptoms. Practical recommendation If you have immediate symptoms (anaphylaxis, hives, wheeze) — see an allergist for skin‑prick testing or ImmunoCAP serum IgE testing (Quest/LabCorp). If you suspect celiac disease — order tTG‑IgA (Quest, LabCorp) before you remove gluten; follow up with GI if positive. If you have bloating/diarrhea after dairy or suspected SIBO — ask GI about hydrogen breath testing. If symptoms are chronic, nonspecific (bloating, fatigue, headaches, IBS‑type) — work with an experienced RDN to do a structured elimination and re‑challenge (low‑FODMAP or empiric elimination) and keep a food–symptom diary. If you want a lab test, prefer validated tests run by reputable labs (ImmunoCAP for IgE; tTG for celiac; breath tests via GI clinics). Avoid paying for broad IgG panels to guide long‑term diets. If you want, tell me your main symptoms and I’ll recommend the most appropriate validated test or clinician to see (allergist, GI, or RDN) and how to proceed.

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