You do not feel well after eating a particular food, even if it is well known as a healthy food. You may notice that you have symptoms such as headache, joint pain or excess bloating.  You are not sure if the particular food is responsible for your symptoms, so you eat that food again on a different occasion, and the same symptoms come back. The symptoms may appear within few hours or up to 3 days after eating that food. May be it is an existing symptom such as joint pain that gets worse after eating that food. In that case, you may have sensitivity to that particular food.

Food sensitivity

How is food sensitivity different from food allergy?

You probably have a friend, colleague or even a family member with food allergies. You know that if they eat very small quantities of the allergenic food, they will have an adverse reaction within a short period of ingesting that food and it may even be life threatening.

Common food allergy symptoms are hives, swelling of lips, tongue, throat or other parts of the body, abdominal pain, nausea, vomiting, breathing difficulty to life threatening Anaphylaxis. When allergenic food is eaten, the immune system releases immunoglobulin (IgE) antibodies, leading to excess release of histamine that is responsible for the allergy symptoms. 

Food allergies typically develop in Childhood and except for tree nut/peanut allergies, many are outgrown by Adulthood. Rarely Adults can develop food allergies. The list of foods commonly known as “big eight” that most often trigger allergic reactions are:

The Big 8

Food sensitivity on the other hand, leads to less serious symptoms.

Big 8 food allergens

Do I have food sensitivity? 

Not to be confused with IgE mediated “true” food allergy, food sensitivities that result in elevated IgG antibodies when eating a particular food, are said to cause or atleast exacerbate multiple symptoms. Some of the health conditions associated with food sensitivities are listed here:

  • Irritable Bowel Syndrome (IBS)
  • Asthma
  • Migraine
  • Fatigue
  • Urticaria
  • Rhinitis/sinusitis
  • Eczema/Psoriasis
  • Gastrointestinal symptoms such as excess gas/bloating symptoms, nausea, constipation, diarrhea
  • Joint pain
  • Autoimmune conditions
  • Mood issues
  • ADHD/focus issues
  • Crohn’s disease

Top list of foods frequently known to trigger food sensitivities are

  1. Wheat
  2. Other gluten containing grains such as rye, barley
  3. Cow’s milk/ Dairy products
  4. Egg yolk
  5. Corn
  6. Soy
  7. Nuts
  8. Citrus fruits
  9. Night shade vegetables (tomatoes, potatoes, eggplant, peppers)
Nightshade vegetables

How to test for food sensitivity? How is it different from food allergy testing?

Food allergies can typically be tested using the skin prick test performed at an Allergist office or IgE blood test ordered by your Physician.

Food allergy testing

For food sensitivity testing, many labs provide serum tests to test for IgG antibodies against specific food antigens. Some labs even provide dried blood spot test kids so you can have food sensitivity testing done at the comfort of your own home. There are some concerns that the tests can return false positive results. Improvement in symptoms on eliminating the food/foods tested positive for IgG antibodies can help confirm the results.

Elimination-Rotation diet remains the gold standard in identifying food sensitivities.But it needs strict adherence of the elimination diet, which is not always easy to follow.

Do you have Food intolerance symptoms? Food intolerance vs food sensitivity

Food intolerance is often interchangeably used with food sensitivity. But the main difference is food intolerance is not mediated by the immune system and mostly limited to Gastrointestinal disturbances such as constipation, excess bloating symptoms among others.

Some of the non-immunological causes of food intolerance are digestive enzyme deficiency, sensitivity to any component of that food – not just the protein part, poor absorption of a certain nutrient from the food. Lactose intolerance is a type of food intolerance as people with lactose intolerance do not produce sufficient lactase enzyme to digest lactose in milk. Histamine intolerance is another example.

How to test for food intolerance?

Elimination rotation diet challenge can help you identify food intolerance. Additional functional or conventional lab testing for enzyme levels may be needed to identify the real cause of the food intolerance and address symptoms.

Your takeaway

If you are not sure whether your symptoms are due to food sensitivity, food intolerance or even food allergy, talk to your health care provider about testing. If you try the Elimination diet on your own, it is still important that you talk to your health care provider to avoid nutrient deficiencies that may arise when you are eliminating certain foods long term.

The information and other content provided in this blog are for information purpose only, and not intended and should not be considered as medical advice. If you have a medical concern, you should consult with your health care provider before you make any changes to your diet or lifestyle.


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