Food Intolerance Test: Purpose, Procedure, and More
Medically Reviewed By
Prof. Ashok Rattan
Written By Sheena Mehta
on May 6, 2025
Last Edit Made By Sheena Mehta
on Jul 19, 2025
Hey!
Did you experience bloating, tiredness, or unwell after consuming certain foods? And you are utterly clueless about it.
If yes, you may need a food intolerance test. Unlike food allergies that show immediate reactions, food intolerances often take time to show symptoms.
Did you know?
- The food intolerance test is also known as the total IgG test, allergy-specific IgG test, and food sensitivity test.
- Children are most affected by food intolerances. More than 5% of children all over the world have food intolerance. However, these allergies go away with age.
Common foods that can trigger symptoms include:
- Milk
- Soy
- Eggs
- Wheat
- Shellfish
- Peanuts
- Nuts
- Wheat
- The National Health Service (NHS) does not recommend IgG-based food intolerance tests on a routine basis. The NHS says that when experiencing food intolerance, consult a specialist (dietician) to determine whether you have a food intolerance or food allergy.
So, why wait? The blog provides insights into the food intolerance test, how it works, and whether it is right for you.
Understanding the Food Intolerance Test in Detail
In simple words, food intolerance means difficulty in digesting certain foods. It is different from food allergies. Food intolerance or food sensitivity occurs when your body has a chemical reaction to certain foods and can’t tolerate them. Consuming these foods may cause harmless symptoms.
8 Common Symptoms Associated with Food Intolerance Test
- Bloating or gas
- Stomach Pain (Mild to Intense)
- Diarrhea or constipation
- Headaches or migraines
- Fatigue
- Rashes
- Itchy skin or rashes
- Brain Fog
Additionally, these symptoms can take hours or days to appear after consuming trigger foods. So, identifying the cause of their occurrence is challenging.
What is the purpose of a food intolerance test?
A healthcare provider may suggest a food intolerance test if you face symptoms caused by eating certain foods and non-allergic reactions in your body.
It may also be ordered if some risk factors are involved.
- Family history of food intolerance: You are at an increased risk of developing food allergies when conditions like eczema and hay fever are genetic. This impact of a family history of allergy can lead to a food intolerance test.
- Food allergies: An allergy to a particular food may require a food intolerance test to determine whether you are allergic to that food or just sensitive to it.
- Asthma: Some foods or food allergies can cause asthma. Hence, a food intolerance test may be suggested.
Additionally, food intolerance symptoms frequently impact several body parts. However, food allergy symptoms are frequently observed in the following body parts:
- Skin reactions include redness, tingling, itching, and hives. Pink bumps that look like bug bites can develop in babies.
- Respiratory system: Your respiratory health may also suffer, causing coughing, trouble breathing, wheezing, nasal congestion, and chest tightness.
- Digestive system: Food intolerance or insensitivity can harm the digestive system. It can cause itching, swelling of the tongue, pain in the abdomen, and a metallic taste in the mouth.
Also read: https://redcliffelabs.com/myhealth/allergy/food-allergy-symptoms-diagnosis-treatment/
Note: If you experience these symptoms, get a food intolerance test done quickly. Early detection can help detect potential health issues at their earliest. Timely diagnosis and timely treatment can help improve treatment outcomes.
Other Reasons When A Doctor May Prompt a Food Sensitivity Test:
Sometimes severe anaphylactic shock may also happen due to food intolerance, including:
- Fast pulse
- Swollen lips, throat, or tongue.
- Trouble breathing
- Pale Skin
- Dizziness
- Feeling faint
Hence, your healthcare provider may prompt a food intolerance test to help detect allergic substances. Without proper medical care, the condition can become too serious or fatal.
What does the food intolerance test detect?
A food intolerance or sensitivity test helps detect your body’s adverse reaction to certain foods caused by difficulty digesting or processing those foods. Through the following tests, a doctor can identify foods that may be causing bloating, gas, diarrhea, headaches, and fatigue in your body.
1. IgG antibodies
Unlike food allergy, which is IgE-mediated, the food intolerance test looks for IgG antibodies that may be formed hours or days after eating non-favorable foods. These antibodies are important in fighting infections from bacteria and viruses. High levels may indicate a sensitivity.
2. Lactose intolerance
A lactose intolerance test is the most common and involves a series of blood tests. This is to measure the amount of glucose in the body.
3. Gluten sensitivity
If you are gluten-sensitive, it can cause gastrointestinal problems and other problems. You might feel tired, nauseous, or bloated. Gluten intolerance is also called non-celiac gluten sensitivity.
4. Fructose or sorbitol intolerance
A food intolerance test also helps detect whether you are sugar-sensitive,. Hence, you should avoid chewing gum, ice treats, and syrups for a fever and a cold. Common fructose or sorbitol intolerance signs include abdominal pain, diarrhea, and low blood sugar (hypoglycemia).
5. Histamine intolerance
The Hislps measure the enzyme diabreakxidase (DAO) levels, which break down histamine in foods.
Preparation for the Food Intolerance Test
No special preparations are required for a food sensitivity test. However, to get the most accurate results, follow these instructions.
- No fasting: You need not fast before a food intolerance test. This allows you to eat meals and drink beverages except alcohol, and won’t affect your test results.
- No intense exercise: No smoking or strenuous exercise the day before the test. Otherwise, engaging in physical activity may cause shortness of breath, fatigue, and hormonal fluctuations.
- Stay hydrated:The test involves a blood draw, so drink water before appearing for the test to help avoid multiple punctures.
- Maintain a food journal: Record your meals, snacks, beverages, and symptoms.
Additionally,
- Eliminate suspected foods from your diet after your doctor says. Otherwise, it may lead to false negatives.
- Inform your healthcare professional about regular medications, including heart and sugar medications. He may ask you to stop or continue taking them, as their ingredients might interfere with the test results.
Note: Discuss the smallest doubt with your healthcare provider before the test to improve the accuracy of your food intolerance test report.
Procedure of the Food Intolerance Test
The procedure of food intolerance begins with a physical exam and involves a few questions, including symptoms.
He will choose from the following tests to determine the cause of food intolerance in your body.
1. Oral challenge test
During the oral challenge test (OCT), a healthcare provider ingests small amounts of the food that might be causing your allergy. Besides, it involves taking an injection or capsule of a certain food.
An oral food challenge test is one of the most reliable tests often included in a food intolerance test to help closely monitor for any signs of allergic reactions.
2. Elimination test
As the name says, the elimination test helps a doctor discover foods causing the allergy. He will suggest eliminating all suspected foods from the diet. Gradually, you can include them in your diet and see allergic reactions.
3. Skin prick test
In a skin prick test, a healthcare provider places a small amount of food directly on the skin, which is then pricked with a needle, allowing it to enter. If you develop itchy lumps that resemble a bug bite, it indicates you are allergic to that food.
4. Blood test
A blood test for food intolerances is performed to check the presence of IgE antibodies. These antibodies are formed when your body is exposed to an allergic substance.
A food intolerance blood test draws a small amount of blood from your vein. The blood sample is sent to a laboratory for analysis, and the reports are typically available within a stipulated timeframe.
What do the food intolerance test reports indicate?
A food intolerance test checks the presence of circulating immunoglobulin-G (IgG) food or drink antibodies. Elevated IgG levels indicate that you are sensitive or intolerant to suspected foods, which may contribute to chronic symptoms.
Interpretation Of Test Results
| Values under 0.35 | Negative/Undetectable |
| Values under 0.35 -0.69 | Low-level sensitization |
| Values under 0.70-3.49 | Moderate level sensitization |
| Values under 3.50- 17.49 | High-level sensitization |
| Values under 17.50 - 49.99 | Very high-level sensitization |
| Values under 50.00- 100.00 | Almost all food intolerance |
| Values over 100.00 | Food intolerant |
Please book an appointment with our healthcare provider or dietitian for a personalized treatment plan and observe the symptoms change.
What if your food intolerance test reports are positive?
A positive food intolerance test result indicates that the IgG antibodies have been detected against the tested food. It is marked in red. Common food categories include dairy, fruits, vegetables, seafood, grains, etc.
Who should take the food intolerance test?
A food sensitivity test can benefit those individuals who experience discomfort after consuming certain foods.
Food intolerances typically cause digestive or nonspecific symptoms that are hard to pinpoint.
1. Frequent digestive issues
Individuals with frequent digestive issues like bloating, gas, stomach pain after eating, and diarrhea should take a food intolerance test.
2. Chronic symptoms or medically unexplained symptoms
According to the Centers for Disease Control and Prevention (CDC), unexplained chronic symptoms last a year or more. Common signs and symptoms include headaches or migraines, fatigue, joint pain, and skin issues.
3. Family history
A family history of food intolerance or related conditions like irritable bowel syndrome (IBS) usually creates a need for the test.
4. Difficulty identifying trigger foods
Sometimes, despite making dietary changes, it is unknown what foods are triggering symptoms. Therefore, sensitivity is suggested for food in the sensitivity test.
5. Use the elimination method to recognize food sensitivities
Symptoms that improve with elimination diets but return when certain foods are reintroduced.
What are the risk factors associated with the food intolerance test?
A food sensitivity test or food intolerance test is safe & risk-free. It involves minimal risks due to inserting a needle into the vein to draw blood, such as:
- Pain
- Bruising
- Bleeding
- Soreness at the injection site
- Fainting
- Infection
- Hematoma (Blood clot under the skin)
Caution: Do not lift heavy objects for at least 24 hours after the test. Seek medical attention immediately if symptoms do not vanish in 2-3 days.
Book A Food Intolerance Test from Redcliffe Labs at INR 14,000
Get a food sensitivity test from Redcliffe Labs. We are a pan-India omnichannel service provider with the widest home collection network, trusted by more than 70 lakh patients who are served with family-like care.
Honesty in pricing is not just our policy, but vital to ethical business standards. Therefore, the food intolerance test with Redcliffe Labs is just INR 14,000. You can get it at an affordable price with expert testing and 100% report correctness guaranteed.
Call us at +91 898 898 8787 or download the Redcliffe Labs mobile app to book a test online.
Step-by-step information on booking a test online from Redcliffe Labs.
- Visit the official Redcliffe Labs website: https://redcliffelabs.com/.
- Browse or search for the specific test you need.
- Add the test to the cart.
- Complete the payment process online.
Note: You will receive confirmation through SMS and WhatsApp.
Conclusion
The food intolerance or sensitivity test is an advanced diagnostic tool that aids in managing symptoms like bloating, fatigue, or digestive discomfort associated with food sensitivities. Performing the test at home can be dangerous. If you know that your body cannot tolerate certain foods, get a food intolerance test at Redcliffe Labs. Enjoy the care beyond reports.
FAQs:
1. What are the causes of the food intolerance test?
The causes of the food intolerance test include bloating, diarrhea, gluten intolerance, gas, and abdominal pain.
2. Is fasting required for the food sensitivity test?
No. You do not require fasting for the food sensitivity test. It allows you to eat meals and drink fluids except alcohol before appearing for the test.
3. How often should I take a food sensitivity test?
A food sensitivity test is usually recommended every one to two years. Consult your healthcare provider, as you may need the test depending on the frequency of experiencing food sensitivities.
4. What are the benefits of the food intolerance test?
It helps a healthcare provider learn which foods you are allergic to so that they can make dietary adjustments and suggest a treatment plan accordingly.
5. How long does it take to get results for the food intolerance test?
Redcliffe Labs typically provides the food intolerance test results within six days.
6. What is the most accurate way to test for food intolerances?
The most accurate way to test for food intolerances is the oral food challenge test (OGC). It also helps determine whether you have an outgrown food allergy.
7. Can I suddenly have food intolerances?
Yes. You can suddenly have food intolerances due to certain gastrointestinal conditions that can make you easily prone to food sensitivities.
