Intolerance and Allergy: Symptoms and Diagnosis

Updated: Sep 19

Stomach cramps, chronic digestive issues, frequent sniffles, watery eyes... Do you experience any of these or similar symptoms often and don't know what could be causing them? Let's get to the crux of the issue and find out possible causes.

What is the difference between Allergy and Intolerance?

Allergy and Intolerance are often interchangeably used in common parlance. With some common symptoms, it is easy to confuse the two. Here’s how to identify what could be causing you that discomfort:



Food Intolerance is a chemical reaction.

Whereas allergy is an immune response.

Intolerance is limited to the digestive system. It could cause bloating, cramping, Irritable Bowel Syndrome and other chronic digestive disorders.

In contrast, Food Allergy compromises the immune system. Smallest amounts of foods you are allergic to could cause mild to severe reactions like anaphylaxis.

Reactions could happen instantly or also take 12 to 24 hours to reflect. Usually happen when a certain amount of food has been consumed.

Symptoms develop instantly after consumption.

It is important to find the allergens troubling you through professional diagnosis. Especially when the cause is unknown.

Mostly used in respect to foods like gluten and lactose, find out when you should do an Allergy test v/s Intolerance test.

Food Allergy: Ig E

Why and When should one get tested: One should get tested when on exposure to an allergen, the symptoms present immediately or within a few minutes.

In the Ig E mediated reaction the immune system overreacts to a specific condition or substance. For instance, if you are allergic to pollen, which is actually harmless, then it may tend your body to overreact.

What is being tested: In this test Immunoglobulin E specific to the allergen is being tested. Ig E is an antibody which is the first response to an allergic reaction and has a short half life and is present in the serum/plasma for 1-2 days.


  • Tingling or itching in the mouth

  • Itchy red rashes

  • Swelling of the face, mouth, throat or other areas of the body

  • Difficulty in swelling

  • Wheezing or shortness of breath

  • Feeling dizzy

  • Nausea, vomiting, abdominal pain

  • Sneezing or itchy eyes

How to understand reports: the cut off value is 0.35, any level above this is abnormal, and the exposure should be avoided.

What to do after allergy results are out: Consult your physician. Avoid exposure.

The tests at Orange Health that can help you:

Food Intolerance: Ig G

Why should one get tested: Food intolerance usually causes unpleasant symptoms and can lead to chronic conditions. However, unlike food allergy, food intolerance symptoms are generally less serious and often limited to digestive problems.

Causes of food intolerance:

Absence of an enzyme needed to fully digest a food- Example Lactose intolerance.

Irritable bowel syndrome- This chronic condition can cause cramping, constipation and diarrhoea.

Sensitivity to food additives- For example, sulphites used to preserve dried fruit, canned goods and wine can trigger asthma attacks in sensitive people.

Celiac disease- has some features of a true food allergy because it involves the immune system. However, symptoms are mostly gastrointestinal, and people with celiac disease are not at risk of anaphylaxis. This chronic digestive condition is triggered by eating gluten, a protein found in wheat and other grains.


  • Rhinitis

  • Sinusitis

  • Asthma

  • Vomiting

  • Abdominal fullness

  • Bloating

  • Wind

  • Water retention

  • Nausea

  • Constipation

  • Diarrhoea

  • Colic

  • Urticaria

  • Atopic dermatitis

  • Eczema

  • Itching

  • Rrashes

  • Joint pains

  • Arthritis

  • Body ache

  • Weakness

  • Headache

  • Mood change

  • Behaviour problem

  • Depression

  • Anxiety

  • Fatigue

What is being tested: Immunoglobulin G mediates the food intolerance. Can appear up to 72 hours after eating food. Symptoms can last up to weeks

How to understand reports: Results more than 1.0 are indicative of an intolerance to the specific food item.

What to do after allergy results are out: Consult your physician. Avoid exposure.

What is not getting tested: This assay does not test any intolerance arising due to enzyme deficiency or chemical sensitivity.

The tests at Orange Health that can help you: