Please note that intolerance and allergy results are two different things. An allergy involves an IgE immune reaction, which usually triggers immediate and sometimes severe symptoms such as hives, swelling, or breathing difficulties. An intolerance, on the other hand, involves an IgG immune response, which is typically delayed and may cause more subtle symptoms like digestive issues, fatigue, or general discomfort over time.
We often receive questions from customers who are unsure how to interpret their allergy or food intolerance results. For example:
“My allergy test shows no allergies, but I still have symptoms.”
“My food intolerance test shows many red markers, but I don’t feel any symptoms.”
“My test came back green on everything — can this be accurate?”
Here we explain why these situations can happen, and what you should know about interpreting your results.
1. Why your allergy test may be negative even if you have symptoms
Our allergy tests measure IgE antibodies in the blood. These antibodies are responsible for classic allergic reactions. However, there are several reasons why your results might not show a positive result even if you feel symptoms:
Non-allergic hypersensitivity: Conditions such as non-allergic rhinitis or irritant-induced asthma mimic allergic symptoms but do not involve IgE antibodies, so they won’t show up on the test.
Different antigen types: Our panels test for the most common allergens, but it’s impossible to include all existing antigens. Your symptoms may be caused by an allergen not covered in the test.
Chronic urticaria (hives): Many people with chronic hives have no identifiable allergic cause, and tests remain negative.
Cell-mediated allergies: Some immune reactions involve T-cells rather than IgE antibodies. These reactions are not detected by standard blood-based IgE tests.
Local allergic rhinitis: Some people react in the nose or airways without showing IgE antibodies in blood tests. This can only be diagnosed with specialized local provocation testing.
False negatives: No test is perfect. Factors such as the timing of exposure, the severity of reaction, age, or medication use (antihistamines, steroids) may reduce test sensitivity.
2. Why your food intolerance test may show many reactions even without symptoms
Food intolerance tests measure IgG4 antibodies, which can indicate immune responses to certain foods. Seeing many “red” markers does not always mean you are intolerant to all of those foods. Possible explanations include:
Normal immune memory: IgG antibodies often reflect past exposure to foods and are not always harmful.
Gut imbalances: Multiple food reactions can point to issues like gut dysbiosis, SIBO (small intestinal bacterial overgrowth), or increased gut permeability.
Other sensitivities: Some symptoms are triggered by non-immunological factors, such as histamine intolerance, oxalates, or salicylates. These reactions may look like food intolerances but are not true immune responses.
Lack of symptoms: It’s possible to have elevated IgG without experiencing noticeable symptoms. Some people may only react under certain conditions, like stress or poor gut health.
3. Why your test may show everything as green
It is normal for some people to have no measurable IgE or IgG responses in our tests. This does not mean your symptoms are not real - it simply means they may not be related to the markers our tests are designed to detect.
You may have a non-allergic condition (e.g. lactose intolerance, histamine intolerance, IBS).
Your symptoms might be caused by factors not measured in blood-based allergy or intolerance testing.