Are elevated IgG antibodies to foods diagnostic of an intolerance?

No. Elevated IgG to a food indicates immune recognition and exposure, which occurs in healthy individuals who regularly consume that food. Clinical relevance is established through correlation with symptoms and a supervised elimination–rechallenge protocol, not serology alone.

Should I eliminate every food that shows an elevation?

Not automatically. Practitioners typically prioritise foods with the highest antibody levels (Class 2–3) and correlate them with the patient's diet history and symptoms. A structured 4–6-week elimination followed by systematic reintroduction identifies true clinical triggers and prevents unnecessarily restrictive diets.

Can this test diagnose coeliac disease or lactose intolerance?

No. Coeliac disease requires serological testing for tissue transglutaminase IgA and/or deamidated gliadin peptide antibodies, confirmed by duodenal biopsy. Lactose intolerance is an enzyme deficiency diagnosed by breath testing or genetic testing, not by immunoglobulin levels.

Why are IgA, IgG, and IgG4 all measured together?

Each antibody class provides different information: IgA reflects mucosal exposure and may correlate with barrier dysfunction; IgG indicates systemic memory and repeated exposure; IgG4 can signal tolerance or chronic antigen contact. Measuring all three gives a more complete immune profile to guide clinical decisions.

Is fasting or dietary preparation required before the test?

No fasting is required, and patients should maintain their usual diet for at least two weeks before collection so that antibody levels accurately reflect habitual exposure. Avoiding a food beforehand may result in low or absent antibodies, masking a potential reactivity.

How is the sample collected for this panel?

A finger-prick blood spot collected at home using a lancet and filter-paper card provided in the kit. The dried spot is posted to the laboratory in a pre-addressed envelope; no venepuncture or clinic visit is needed.

What if many foods show elevation?

Broad reactivity across unrelated foods often reflects generalised intestinal permeability or systemic inflammation rather than multiple discrete sensitivities. In this case, address the underlying cause—dysbiosis, infection, autoimmune enteropathy—before embarking on restrictive elimination, and consider concurrent testing for permeability or inflammatory markers.

How long do results take and when should I retest?

Results are available in 7–10 business days from laboratory receipt. Retesting is typically considered after 3–6 months of dietary intervention to assess whether antibody titres have declined with elimination and to guide reintroduction, though clinical symptom response remains the primary endpoint.

BML-FSA-003food sensitivity allergyUSA

144 Food Panel: IgA/IgG/IgG4

The 144 Food Panel measures IgA, IgG, and IgG4 antibodies to a broad range of dietary antigens from a dried blood spot. Used in functional and integrative medicine to guide elimination diets for chronic gastrointestinal and systemic symptoms, the panel identifies immune responses to foods, though mainstream allergy bodies do not endorse IgG/IgG4 for diagnosis and recommend clinical correlation…

Biomarkers

Dried blood spot

Sample

7–10 business days

Turnaround

Fasting

What is the 144 Food Panel test?

The 144 Food Panel measuring IgA, IgG, and IgG4 antibodies to a broad array of foods is ordered by practitioners seeking to identify immune responses to dietary antigens that may contribute to chronic gastrointestinal symptoms, systemic inflammation, or other non-IgE-mediated presentations. Unlike IgE-based allergy testing, which detects immediate hypersensitivity, this panel aims to uncover delayed or subacute reactions through measurement of antibodies that are part of the mucosal and systemic adaptive immune repertoire. The test is used in functional and integrative medicine to guide empirical elimination diets, particularly when patients report symptoms—bloating, fatigue, joint pain, skin complaints, or migraines—that do not resolve with standard care and do not fit an IgE-mediated pattern. Results are intended to inform, not dictate, dietary modification: elevated antibody levels are correlated with exposure history and symptoms, followed by supervised elimination and systematic rechallenge to establish clinical relevance. Because the evidence base for IgG and IgG4 testing in food sensitivity is contested and mainstream allergy guidelines do not endorse their diagnostic use, practitioners who order the panel do so as part of a broader integrative assessment rather than as a stand-alone diagnostic tool.

What does the 144 Food Panel test measure?

IgA(Food-Specific Immunoglobulin A)

Range: Class 0 (negative) to Class 3 (high reactivity); laboratory-specific thresholds.Optimal: Class 0 or negative across all tested foods is considered optimal in asymptomatic individuals; elevated IgA to specific foods warrants correlation with exposure history and symptoms rather than automatic elimination.Arbitrary units (AU) / Qualitative class (0–3)

Immunoglobulin A is the predominant antibody at mucosal surfaces, secreted into the gastrointestinal lumen where it binds dietary antigens and limits their uptake. Serum IgA to foods is less abundant than secretory IgA but reflects systemic exposure to food proteins that have crossed the mucosal barrier, whether through increased permeability or normal sampling by gut-associated lymphoid tissue. The presence of food-specific IgA can indicate active mucosal contact with an antigen.

Measurement of food-specific IgA aims to identify mucosal immune responses that may correlate with gastrointestinal symptoms or barrier dysfunction. Elevated IgA to multiple foods has been associated with inflammatory bowel disease, coeliac disease (where it is diagnostically valuable for gliadin), and functional bowel disorders, though the clinical significance of isolated IgA elevations in the absence of IgE or symptoms remains contested.

IgG(Food-Specific Immunoglobulin G)

Range: Class 0 (negative) to Class 3 (high reactivity); laboratory-specific thresholds.Optimal: There is no agreed optimal range for food-specific IgG. Elevated IgG to commonly consumed foods may simply reflect frequent exposure; interpretation should be symptom-driven and supported by supervised elimination–rechallenge rather than serology alone.Arbitrary units (AU) / Qualitative class (0–3)

Immunoglobulin G is the most abundant serum antibody and develops in response to repeated antigen exposure. Food-specific IgG antibodies are produced as part of the normal adaptive immune response to dietary proteins and are detectable in most individuals who regularly consume those foods. IgG does not activate mast cells or trigger immediate hypersensitivity, and its presence reflects immunological memory rather than pathology per se.

The clinical utility of food-specific IgG testing is highly controversial. Mainstream allergy and gastroenterology bodies, including the European Academy of Allergy and Clinical Immunology and the American Academy of Allergy, Asthma & Immunology, state that IgG to foods is a marker of exposure, not disease, and do not recommend elimination based on IgG results alone. Some practitioners in functional and integrative medicine interpret elevated IgG as a signal of immune activation or delayed hypersensitivity and use it to guide elimination–rechallenge protocols, though robust evidence linking IgG levels to symptoms is limited and contested.

IgG4(Food-Specific Immunoglobulin G Subclass 4)

Range: Class 0 (negative) to Class 3 (high reactivity); laboratory-specific thresholds.Optimal: No validated optimal range exists for food-specific IgG4. Mild to moderate elevations in isolation are common with regular consumption and do not mandate elimination; marked elevations warrant clinical correlation and, where symptoms are present, structured dietary intervention.Arbitrary units (AU) / Qualitative class (0–3)

IgG4 is the least abundant IgG subclass and has unique immunological properties: it does not fix complement efficiently, does not cross-link antigen, and can be functionally monovalent due to Fab-arm exchange. It rises with chronic or high-dose antigen exposure and is considered a marker of immunological tolerance in some contexts, notably in allergen immunotherapy where rising IgG4 to aeroallergens accompanies clinical desensitisation.

In the context of food immunology, elevated IgG4 is often interpreted as a sign of tolerance or repeated exposure rather than reactivity, yet some laboratories include it in sensitivity panels and practitioners interpret high IgG4 alongside IgG and IgA to assess the overall immune profile. The role of IgG4 in food reactions is contested: it may reflect tolerance, it may be a bystander marker of exposure, or in rare cases (such as IgG4-related disease affecting the gastrointestinal tract) it may be pathogenic. Interpretation requires integration with clinical history and other antibody classes.

Why is the 144 Food Panel test ordered?

Patients with chronic, unexplained gastrointestinal symptoms—bloating, altered bowel habit, abdominal discomfort—where coeliac disease, inflammatory bowel disease, and structural pathology have been excluded
Individuals reporting systemic or extra-intestinal symptoms (fatigue, joint pain, headaches, skin eruptions) suspected to be diet-related but without clear IgE-mediated allergy
Functional and integrative medicine assessments where a structured elimination diet is planned and serological guidance is desired to prioritise which foods to remove first
Patients with known or suspected increased intestinal permeability (in the context of autoimmune or inflammatory conditions) where food antigen exposure may perpetuate immune activation
Monitoring immune response trends in patients undergoing dietary intervention, to assess whether antibody titres decline with elimination and guide reintroduction timing
Paediatric patients with developmental, behavioural, or gastrointestinal concerns where a dietary trigger is suspected and parents seek objective data to guide a trial elimination, with appropriate counselling that results are exploratory

Sample collection and turnaround

Sample type

Dried blood spot

Fasting required

Collection method

Finger prick

Turnaround

7–10 business days

Collection notes

Patient self-collection using a finger-prick lancet and filter-paper card supplied in the home collection kit. The kit includes detailed instructions, lancets, alcohol wipes, gauze, and a pre-addressed return envelope. Spots must be allowed to dry at ambient temperature (away from direct heat or sunlight) for at least 3–4 hours before sealing and posting. Avoid collection during or immediately after acute illness, which can transiently alter antibody profiles. Ideally, maintain the patient's usual diet for at least two weeks prior to collection so that antibody levels reflect habitual exposure; if a food has already been eliminated for an extended period, antibodies to it may be low or undetectable.

Specimen requirements

Complete filling of all designated circles on the filter card to ensure sufficient sample volume for multiplex analysis. Specimens with insufficient blood, excessive clotting on the card, or contamination may be rejected or yield indeterminate results. Once dry, the card is stable at room temperature for up to 14 days in transit; avoid refrigeration or freezing of the dried spot, which can cause condensation and degrade the specimen.

What can affect 144 Food Panel results?

elevatesRecent consumption of tested foods

Antibody levels reflect exposure, so regular intake of a food in the days to weeks before collection will maintain or increase titres; conversely, foods eliminated for weeks to months may show reduced or absent antibodies, masking prior reactivity.

elevatesAcute gastrointestinal infection or mucosal inflammation

Barrier disruption during gastroenteritis, inflammatory bowel disease flares, or coeliac disease activity increases antigen uptake, transiently raising food-specific antibodies across multiple antigens.

reducesImmunosuppressive or immunomodulatory therapy

Corticosteroids, biologics targeting B cells or cytokines, and other immunosuppressants can blunt antibody production, potentially yielding falsely low or negative results even in the presence of true reactivity.

variableTotal immunoglobulin deficiency or dysregulation

Selective IgA deficiency (present in roughly 1 in 300–700 individuals) abolishes IgA responses, rendering that arm of the panel uninterpretable. IgG subclass deficiencies or hypergammaglobulinaemia also alter results; total immunoglobulin levels may be measured concurrently if deficiency is suspected.

elevatesCross-reactivity between related proteins

Homologous proteins in botanically or zoologically related foods (for example, tree nuts, crustaceans, grasses) can induce antibodies that bind multiple panel antigens, inflating the number of apparent reactivities and complicating interpretation.

variableAge and developmental stage

Infants and young children have developing immune repertoires and mucosal barriers; food-specific antibodies may be transiently elevated during tolerance acquisition or following early exposure, making paediatric interpretation more nuanced.

What do 144 Food Panel results mean?

Elevated

Elevated IgA, IgG, or IgG4 to one or more foods indicates immune recognition of those antigens. For IgA, elevation may reflect active mucosal exposure and can correlate with barrier dysfunction or local inflammation. For IgG, elevation is a marker of repeated exposure and immunological memory; it is present in healthy individuals who consume those foods and does not, by itself, confirm clinical reactivity. For IgG4, elevation may signal tolerance, chronic exposure, or in some interpretations a component of delayed hyperssensitivity. Clinical significance is established through correlation: compare elevated foods with the patient's diet history, eliminate the highest-reactivity foods (typically Class 2–3) for 4–6 weeks while monitoring symptoms, then systematically reintroduce to identify true triggers. Broad elevation across many unrelated foods often reflects generalised barrier permeability or inflammation rather than multiple discrete sensitivities and warrants investigation of the underlying cause (gut dysbiosis, infection, autoimmune enteropathy) before embarking on restrictive elimination.

Normal

A result in the normal or Class 0 range for all tested foods suggests no significant adaptive immune response to those antigens at the time of testing. It supports the hypothesis that symptoms are not driven by IgA/IgG/IgG4-mediated food reactions, though it does not exclude IgE-mediated allergy (which requires separate testing), non-immune intolerances, or reactions to foods not on the panel.

Reduced

Low or absent antibodies to a food indicate either minimal recent exposure or, in the case of IgA, possible selective IgA deficiency. A negative panel does not exclude food intolerance, as non-immune mechanisms (enzyme deficiencies such as lactase, osmotic effects of FODMAPs, pharmacological effects of vasoactive amines) are not detected by antibody testing.

Note: This panel measures immune markers of exposure and memory, not disease. Mainstream allergy and gastroenterology bodies do not endorse IgG or IgG4 testing for the diagnosis of food allergy or intolerance, and the predictive value for clinical symptoms is debated. Results should guide rather than dictate dietary intervention: use them to prioritise an empirical elimination, then rely on symptom response and rechallenge to confirm clinical relevance. Avoid unnecessary long-term restriction based on serology alone, particularly in children, where overly restrictive diets risk nutritional deficiency and disordered eating. Consider total immunoglobulin levels if widespread reactivity or deficiency is suspected, and interpret paediatric results with caution given the developmental context of oral tolerance.

Frequently asked questions

IgE testing detects immediate, potentially life-threatening allergic reactions mediated by mast-cell degranulation. IgG (and IgA/IgG4) testing measures antibodies associated with delayed or subacute immune responses and is used in functional medicine to identify possible food sensitivities, though mainstream allergy bodies consider IgG a marker of exposure rather than disease.

How to access the 144 Food Panel test

The 144 Food Panel reference page is free and open to all practitioners. Create a free practitioner account to see pricing, save tests to your list, and generate requisition forms. Verification takes 1–2 business days.

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About this page

Published: October 7, 2026

Last reviewed: October 7, 2026

References:

Stapel SO, et al. Testing for IgG4 against foods is not recommended as a diagnostic tool: EAACI Task Force Report. Allergy. (2008)
Carr S, et al. CSACI position statement on the testing of food-specific IgG. Allergy Asthma Clin Immunol. (2012)
Bischoff SC, et al. Intestinal permeability — a new target for disease prevention and therapy. BMC Gastroenterol. (2014)
Gocki J, Bartuzi Z. Role of immunoglobulin G antibodies in diagnosis of food allergy. Postepy Dermatol Alergol. (2016)
Lavine E. Blood testing for sensitivity, allergy or intolerance to food. CMAJ. (2012)

This content is for licensed healthcare practitioners only and does not constitute medical advice. Clinical decisions should be based on the full clinical picture and not on any single test result.