Home food allergy tests allow people to easily and conveniently test for allergens without having to visit a doctor, and the popularity of these tests is growing. In this article, we break down what a food allergy is, the differences between food allergies, food intolerances and food sensitivities and what you can expect from a home food allergy test.
The body’s immune system is always working to identify and eliminate harmful bacteria or viruses. A food allergy happens when the immune system misidentifies a harmless food as a threat. An allergic reaction may occur soon after eating the triggering food — called an allergen — and even a tiny amount of an allergen can cause symptoms such as digestive problems, hives, or swollen airways.
In some people, a food allergy can cause severe symptoms or even a life-threatening reaction known as anaphylaxis.
It’s estimated that food allergies affect 8% of children under the age of five, and up to 4% of adults. It’s still unknown why some people develop allergies to food, although these individuals often have other allergic conditions, such as asthma, hay fever, or eczema.
Having experienced eczema as an infant is a known risk factor for childhood food allergies. The worse the child’s eczema is and the earlier it starts, the likelier they are to have a food allergy. While there's no cure for a food allergy, some children do outgrow allergies as they get older.
Types of food allergy
There are two major types of food allergies:
IgE-mediated food allergy
This is the more common of the two types, triggered by the immune system producing an antibody called immunoglobulin E (IgE). Symptoms occur a few seconds or minutes after eating, and there’s a greater risk of anaphylaxis with this type of allergy.
Non-IgE-mediated food allergy
This type isn’t caused by IgE but by other cells in the immune system, and it’s often difficult to diagnose as symptoms take several hours to develop.
In rare cases, a person may experience symptoms from both types of food allergy.
Common food allergies
In the United States there are 8 major food allergens that need to be mentioned when they are used as ingredients:
Food intolerance vs. food allergy
It's easy to confuse a food allergy with a food intolerance also known as a food sensitivity. Intolerances are far more common, and while they can be annoying and distressing, they usually produce symptoms that are less serious than most food allergies.
Food intolerances are caused by the body’s inability to properly process a food, triggering the digestive system rather than the immune system. Food intolerances are typically identified through methods like an elimination diet, where you remove a particular food, rather than testing.
Dairy, gluten, and caffeine are common food intolerances. Typical gastrointestinal symptoms can include gas, bloating, stomach pain, diarrhea, constipation, and nausea.
Symptoms of a food allergy
For some people, an allergic reaction to a food may be uncomfortable but not severe, but for others it can be life-threatening.
Food allergy symptoms usually appear within a few minutes to two hours after eating the allergen. In rare cases, symptoms may be delayed for several hours.
Classic allergy symptoms include:
Abdominal cramping or pain, nausea, vomiting, or diarrhea
Itching, hives, or eczema
Flushing of the face
Swelling of the lips, face, tongue, throat, or other parts of the body
Runny nose, nasal congestion, sneezing, coughing, wheezing, or difficulty breathing
Dizziness, lightheadedness, or fainting
Pain or tightness in the chest
If you experience any of these symptoms, it’s important to see a doctor for an initial diagnosis. If your symptoms are mild but persistent, you may want to visit a specialist healthcare professional – for example, a dermatologist if your skin is being affected.
In some people, a food allergy can trigger a severe allergic reaction called anaphylaxis. This can cause life-threatening symptoms, including:
Constriction and tightening of the airways
Swollen throat or the sensation of a lump in your throat that makes it hard to breathe
Shock, with a severe drop in blood pressure
Dizziness, lightheadedness, or loss of consciousness
Treatment for a food allergy
The best way to prevent an allergic reaction is to identify the food that causes it and avoid that food. But it’s important to consult a doctor before making radical changes, such as cutting out dairy products, to your or your child’s diet.
Antihistamines can help relieve the symptoms of a mild or moderate allergic reaction. A higher dose of antihistamine is often needed to control acute allergic symptoms.
Emergency treatment is necessary for anaphylaxis as left untreated, it can lead to a coma or even death. Adrenaline is an effective treatment for more severe allergic symptoms, such as anaphylaxis. People with a food allergy are often given a device known as an auto-injector pen that can deliver a dose of adrenaline in an emergency.
Taking at-home allergy tests
All home allergy testing kits include detailed instructions and all the materials you need to collect the required blood sample. After pricking your finger, you’ll squeeze a few drops of blood onto the collection card provided before sending it back for testing. You’ll usually receive your results in a few days to a couple of weeks.
Are at-home allergy tests accurate?
Home testing is very convenient, and for people who suspect they may have a mild food allergy, an at-home test could be a good first step to identifying the potentially problematic food(s).
However, home food allergy tests are not as comprehensive or conclusive as food allergy tests administered by a medical professional in person, and the test results may miss other relevant allergies. For example, IgE and IgG testing doesn't detect potentially serious food-induced conditions like celiac disease.
While an at-home test may reveal the potential for a food allergy, the best and most reliable way to find out for certain whether you have a food allergy is to make an appointment with your doctor or healthcare provider. They will be able to rule out other potential causes of your symptoms and refer you to a specialist for tests. The results of these tests will help determine the best course of treatment and provide guidance on safely making necessary dietary changes.
Depending on your symptoms and their severity, the tests you may have include:
Skin-prick test, where a drop of liquid containing a food you may be allergic to is put on your skin to see whether it reacts
Intradermal test, where the suspected food allergen is injected into the skin to detect weaker allergic reactions
Skin scratch test, where a small area of skin is removed and the potential allergen is rubbed over the area, allowing it to reach deeper layers of tissue
Trialling a special diet, where you avoid eating the specific foods that might be triggering allergic reactions, to and see if your symptoms ease
You may also be asked to keep a food and symptoms diary to help identify what may be triggering your symptoms.
Looking to launch home food allergy tests?
If you’re a digital health company looking for turnkey access to home food allergy tests speak to our lab testing team now! They’ll learn more about your requirements and guide you through the entire process whether you’re looking to launch or scale food allergy testing.
At Vital, we offer a variety of food allergy and intolerance testing options. Popular food allergy and intolerance tests include:
Our lab testing platform enables you to activate speciality lab testing across 47 States within a matter of days (rather than months) with no pre-existing lab accounts. Send fully white-labeled test kits directly to your patient's door. Our platform handles labs end-to-end, from the point of order, through to kitting, fulfilment, sample collection, lab processing and results retrieval. We give you full visibility to order and track the status of your labs via dashboard or API.