Food Detective — IgG Food Intolerance Test (50 Foods)

The Food Detective test is a point-of-care IgG food intolerance test that measures immune reactivity to 50 common foods from a small blood sample, with results delivered within the same one-hour appointment. It detects IgG-mediated delayed food reactions — the type linked to chronic, low-grade inflammatory symptoms that are difficult to connect to specific foods because they appear hours or days after eating. Unlike IgE allergy tests (which detect immediate, often severe reactions), IgG food intolerance testing maps the broader landscape of foods generating a sustained immune response. At Celostní medicína a Akupunktura Brno, Eva Hajská uses the test as a diagnostic tool within her naturopathic and TCM practice to identify dietary contributors to skin conditions, digestive complaints, fatigue, headaches, and inflammatory disorders — then builds an elimination and rotation protocol based on the results.

The Food Detective test (manufactured by Cambridge Nutritional Sciences, used widely in integrative and naturopathic practices across Europe) is a semi-quantitative IgG antibody test that screens for immune reactivity to 50 food antigens simultaneously. The test works by exposing a patient blood sample (obtained via fingerprick or a small venous draw) to food antigen extracts in a point-of-care format — no laboratory courier is needed because the entire test runs on a compact test unit in the clinic, returning results within approximately 40 minutes. The 50 foods tested span the most common reactive categories in the Central European dietary context: cow's milk and dairy products (including casein and whey proteins), gluten-containing grains (wheat, rye, barley), eggs, meats, seafood, nuts and seeds, legumes, fruits, and vegetables. The result for each food is semi-quantitative — a colour scale indicates the degree of reactivity, from absent through borderline to elevated. IgG food intolerance differs mechanistically from classic IgE food allergy. IgE-mediated reactions involve mast cell degranulation and histamine release — typically fast (within minutes) and potentially anaphylactic. IgG-mediated reactions are slower (onset 2–72 hours after consumption), dose-dependent, often cumulative, and clinically manifest as chronic, non-specific symptoms: bloating and altered bowel habits, skin problems (eczema, acne, urticaria), persistent fatigue, brain fog, headaches and migraines, joint inflammation, and mood disturbance. Because the connection between the food and the symptom is temporally separated, these intolerances are rarely identified through dietary recall alone. At this practice, Food Detective results are interpreted by Eva Hajská within the context of the patient's complete symptom picture, TCM diagnosis, and dietary history. Reactive foods are not simply excluded wholesale; instead, Eva builds an individualised approach — a temporary elimination of high-reactivity foods for 8–12 weeks, supported by gut-healing phytotherapy and nutritional guidance, followed by structured reintroduction to assess symptom response. This integration with herbal medicine and TCM pattern correction is what distinguishes the test's application here from a standalone food intolerance screen. The test session lasts approximately one hour: brief intake discussion (15 minutes), blood collection and test running (40 minutes), results interpretation and dietary planning discussion (remaining time). No fasting is required before the test. Patients are advised to continue their usual diet in the week before testing — avoiding specific foods beforehand can suppress IgG levels for those foods and produce a false-negative result. This test is particularly valuable for patients with unexplained digestive symptoms, chronic skin conditions unresponsive to conventional treatment, persistent fatigue without clear cause, recurrent headaches, and conditions with a known inflammatory dietary component such as rheumatoid arthritis or eczema.