Food allergy is one primary problem that is annoying and often life-threatening. According to Food Allergy and Research Education (FARE), nearly 32 million Americans have food allergies. More than 170 foods (peanut, eggs, milk, soy, wheat, etc.) have been reported to cause an allergic reaction.
Few tests can assist an expert allergist in ascertaining if you have food allergies. However, is food allergy testing accurate? Not totally. The test ( skin-prick test and blood test) only reports the chance of having a food allergy. To get maximum accuracy, doctors often suggest oral challenges and examine your history. In this article, we will explore what food allergy is, the tests to detect food allergy, and 7 fascinating facts about food allergy testing accuracy.
What is Food Allergy?
A food allergy refers to the unusual reaction of your body’s immune system to specific foods. Depending on the intensity, your allergy can be mild and severe. When you eat, your immune system is exposed to many different kinds of food protein. Gradually your immune system learns about that food protein, remembers them, and categorizes them as harmless. Food allergy occurs when your immune system interprets specific food proteins as harmful. Food proteins that trigger allergic reactions to your body are food allergens.
When you eat your food allergens, your body’s immune system produces a type of antibody, Immunoglobulin E, aka IgE antibodies. These antibodies work against those food proteins by interacting with the cell of your immune system that contains inflammatory agents like histamine. This large and quick production of histamine and other inflammatory agents causes inflammation and triggers an allergic reaction to your body. This inflammation can affect your skin, respiratory tract, gastrointestinal system, or cardiovascular system.
Sign and Symptoms of Food Allergies
Food allergy symptoms appear like lightning and may include the following.
- Hives
- Swelling
- Wheezing
- Coughing
- Difficulty breathing
- Vomiting
- Faintness
- Weakness
- Blackout
What Is The Difference Between Food Allergy and Food Intolerance?
Food allergy and food intolerance both are upsetting and irritating, but they are not the same. The main difference between food allergy and food intolerance depends on how they are affecting your body. Food allergy deals with your immune system by reacting to the food proteins. On the other hand, food intolerance is not an immune system reaction; instead, it’s an issue with your digestive system.
Food intolerance will occur if you don’t have a specific enzyme to digest your food thoroughly. Lactose intolerance is an example of food intolerance where you lack the lactase enzyme to digest the natural sugar lactose in milk. A major difference between food allergy and food intolerance is that you should not eat any food you are allergic to. Contrarily, people with food intolerance can consume a small amount of the troubling food. Moreover, a food allergy needs to be diagnosed, whereas food intolerance may not need any test. However, is food allergy testing accurate? Let’s explore the 7 fascinating facts about food allergy testing accuracy.
7 Fascinating Facts about Food Allergy Testing Accuracy
Food allergies are tricky and often difficult to detect. There are a few facts that you should know about food allergy testing accuracy.
Your History and A Physical Examination
If you have symptoms of food allergy, your allergist will perform a detailed physical examination. Most importantly, he will check your medical history to know if your symptoms are connected to a food allergy. Your detailed history also helps to narrow down what food is the reaction-triggering allergen. Moreover, your detailed history and examination determine the allergist to perform further tests or what food should be tested. Often a history and an examination result in “no need for allergy tests,” too.
Food Allergy Testing Accuracy
Skin-prick tests and blood tests are the two tests doctors primarily suggest for patients with allergic symptoms. However, are food allergy blood tests accurate? What is the food allergy testing accuracy of a skin-prick test? Let’s find out.
Skin prick tests: In the test, the doctors make a small cut on your skin to put a food protein extract so that your immune system in the skin comes in contact with the infusion.
If a hive-like bump appears and reaches a specific size, it indicates the IgE antibody formation against the food protein, and your test result will come positive.
Food-specific IgE antibody blood tests: In a medical lab, the technician will take a small amount of blood to analyze the amount of a food-specific IgE antibody. You may ask if food allergy blood test results explained your condition?
If the IgE antibody level is above normal, it indicates that your immune system makes an IgE antibody to the specific food protein. Therefore, your test result will be positive. Blood test results usually take several days to arrive. However, the accuracy of food allergy blood testing and skin-prick testing is not always reliable. Your test result may come positive even if the food is not causing any reaction, or it may come negative while you are having severe allergic symptoms. Many make an IgE antibody to a specific food while not being allergic to it. If you do a test for that food, your result may come positive due to the presence of IgE antibodies in your blood.
However, effective for environmental allergy, it may not be an accurate diagnosis for food allergy. Though it sounds unbelievable, skin prick test results maybe 60% to 80% wrong 60. Nevertheless, in the hands of an experienced doctor like Dr. David Nazarian, blood and skin tests are notably effective where your results are evaluated in the context of your medical history. If your test results are positive and you have a history of an allergic reaction, you have a food allergy. For this, your history is essential.
Schedule Appointment for Food Allergy Testing
Interpreting Results
Skin prick test and IgE antibody blood test results are not effective at predicting the severity of food allergy. Instead, the test results only give information about the possibility that there is an allergy. But not with a “Yes” or “No.”
False-Positive Results
Food Allergy Tests: blood tests and skin-prick tests often end up with a false-positive result. The test result may come positive even though you are not allergic to the suspected food allergen. Many people produce IgE antibodies to a specific food; however, their immune system may not instigate an allergic reaction. So, your test may be positive due to IgE production, but you do not have a food allergy. You are only sensitive to that food.
False Negative Result
Like a false-positive result, your tests may deliver false-negative results. The reason is these tests measure your reaction to the undigested food proteins. Therefore, after food digestion, your IgE may not detect the food protein in your body. Another reason for the false-negative results is if you do the test right after an allergic reaction, most probably, your antibodies are used. So, the tests may not detect it. So, doctors often perform the test later again. The food extract that is used in the skin-prick test is normally processed from the original food. However, while processing, the shape of the food molecules may change that can no longer instigate allergic antibodies. As a result, your test result may come negative.
Oral Food Challenge Accuracy
When your test results are not accurate enough, your allergist may suggest an oral food challenge test. It is the “gold standard” of authenticity to confirm an allergy diagnosis. During an oral food challenge (OFC), you will eat a troubling food allergen under the close supervision of doctors in the clinic for any type of reaction. As there is a higher risk of reaction, you will begin with a low portion of the food and gradually receive increasing portions. Over the testing hour, the doctor will strictly monitor you for any signs of a reaction. If you reach the amount equal to a normal portion without reacting, the food is safe to eat. If you experience a reaction, the doctors stop the OFC with a positive result and an accurate diagnosis.
Food Allergy Tests For Babies
Can a baby do a food allergy test? Or are food allergy blood tests accurate for a baby? Simply put, there is no minimum age for food allergy testing; babies can be tested for food allergies. The pediatric allergists do regular skin-prick tests and blood tests to monitor the intensity of a food allergy. This helps them determine when the child has overgrown the allergy so they can add the food to the baby’s diet.
Final Thought
Food allergy is a common problem most people experience. But people often get confused with their results. The 7 fascinating facts about food allergy testing accuracy can assist you in determining your steps. Contact Dr. David Nazarian at Hormone Replacement Therapy Los Angeles. In his expert hand, you can get an accurate diagnosis and treatment of your food allergy.
