A food allergy occurs when your body’s immune system reacts to a certain food. Most allergic reactions are mild, but some can become serious and even life-threatening. Depending on the type and severity of the allergy, symptoms can be treated through medication and education.
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What Are Food Allergies?
Food allergies occur when your body has an immune reaction to a specific food that you come into contact with or ingest. Your body misjudges a certain food as harmful and, in response, may react by causing hives, difficulty breathing, and an upset stomach. While most food allergies are mild, some can become life-threatening and cause anaphylaxis, which is the swelling of airway passages that cuts off breathing and drops blood pressure.
If someone is having an anaphylaxis episode, call 911 or take them to the emergency room immediately.
What are the types of food allergies?
While there are many types of food allergies, the most common are:
- Eggs.
- Fish.
- Milk.
- Peanuts.
- Seasame.
- Shellfish, like crab, lobster, and shrimp.
- Soybeans.
- Tree nuts, including almonds, Brazil nuts, cashews, hazelnuts, pecans, pistachios, and walnuts.
- Wheat.
While allergies to these foods account for almost 90% of all food allergies, people can also have mild allergic reactions to certain fruits, vegetables, meats, and other items.
Some people experience an itchy throat and mouth after eating certain raw fruits and vegetables, a condition known as oral allergy syndrome.
How common are food allergies?
Experts believe up to 10% of people in the United States have some kind of food allergy. Many children outgrow certain food allergies by adulthood, especially allergies to wheat, eggs, milk, and soy.
What causes food allergies?
Food allergies occur when the immune system overreacts to a certain food. Your body mistakenly reacts to the food as a harmful substance, which then causes physical reactions to protect you from the food.
While experts aren’t exactly sure why food allergies occur, they have been able to identify the most common allergens.
Food allergies risk factors
You may have a higher chance of being diagnosed with a food allergy if you:
- Have asthma or eczema.
- Have a family member with a food allergy, asthma, or eczema.
- Have had an allergic reaction to a food in the past.
Food allergies can show up at any age, but they are more common in babies and children.
Complications of food allergies
If you have a food allergy, you may be at risk for anaphylaxis — swelling of the airways — that can be fatal. It is important to be educated on how to minimize your exposure to allergens, and to have the right rescue medication with you.
How can I prevent food allergies?
Although there is nothing you can do to prevent the allergy itself, you may be able to prevent allergic reactions by taking steps to avoid allergy-causing foods and following your doctor’s advice regarding treatment of known food allergies.
If you are pregnant or breastfeeding, eating common allergens can help expose your baby to these foods. Talk with your baby’s doctor about introducing certain allergens, and feed your baby a variety of common allergen foods to reduce their risk of developing an allergy later.
What Are the Signs and Symptoms of Food Allergies?
Symptoms of food allergies are caused by your body’s immune reaction to the food and can range from mild to life-threatening. Symptoms usually occur within a few hours of eating the food and can affect your skin, digestive tract, cardiovascular system, or respiratory tract.
Symptoms may include:
- A feeling of tightness in the chest.
- Abdominal cramps.
- Coughing.
- Difficulty breathing and swallowing.
- Diarrhea.
- Hives or rash on the skin.
- Hoarse voice, tightness in the throat, or difficulty swallowing as a result of swelling in the throat or tongue.
- Itchy mouth, skin, and throat.
- Nausea or vomiting.
- Swelling of the lips or mouth.
- Wheezing.
The most serious type of allergic reaction is called anaphylaxis, which can occur within minutes and is potentially life-threatening.
Anaphylaxis causes:
- A sharp drop in blood pressure.
- Dizziness.
- Loss of consciousness, shock, or cardiac arrest.
When should I see a doctor about my food allergy symptoms?
If you have any symptoms of a mild food allergy, it’s important to talk with your doctor so you can understand how to keep yourself safe from allergic reactions.
If you or someone you know is experiencing symptoms of anaphylaxis, call 911 or go to the nearest hospital Emergency Department. Anaphylaxis can become fatal quickly.
How Do You Diagnose Food Allergies?
First, your doctor will ask you questions about your symptoms, health history, and family history. They will want to know as much information as you can provide about the allergic reaction and the food you consumed.
They may ask:
- All the symptoms and their severity and duration.
- How much of the food you consumed.
- How quickly symptoms appeared after eating the food.
- If the food was cooked or raw.
- What foods you ate that may have caused the reaction.
- Whether you experience asthma or eczema.
Your doctor may also conduct a physical exam in the areas where your symptoms occurred.
But the most accurate way to diagnose food allergies comes from specific allergen testing.
Tests to diagnose food allergies
- Skin testing — Skin testing, also called scratch testing, exposes your skin to small amounts of allergens (allergy-causing substances) and can identify food allergy triggers, such as peanuts, tree nuts, eggs, milk, fish, shellfish, wheat, and soy.
- Blood tests — Blood tests measure the amount of immunoglobulin E (IgE) antibodies in your blood that are specific to certain allergens. Although blood tests are not as exact as skin tests, your doctor may use them in combination with skin tests to diagnose and treat your allergy.
- Oral food challenge (OFC) — OFC is a test that is used to confirm or rule out a food allergy. During the test, you will eat small, gradually increasing amounts of a suspected allergy-causing food under medical supervision and be monitored for signs of an allergic reaction.
Food allergy prognosis
If you are diagnosed with a food allergy, you will have to adapt your lifestyle and diet to avoid your allergens. Your doctor may recommend continued allergy tests over time to see if you or your child have outgrown the allergy.
Thankfully, with thorough education and successful medications, people with all types of food allergies can live healthy, full lives. Many food companies offer items that are safe for people with many food allergies.
How Do You Treat Food Allergies?
The easiest way to avoid allergic reactions is to know the foods that cause them and avoid consuming those foods.
However, accidents can happen, and certain treatment options have proved to be successful treatment options for mild allergic reactions.
Medications to treat food allergies
- Allergy medications — Some medications may help control mild allergic reactions to food, but may not be suitable if you have a severe or life-threatening allergy. Before you use any allergy medication, you should ask your doctor if it is right for your condition and symptoms.
- Epinephrine — If you are at risk of experiencing a severe or life-threatening allergic reaction called anaphylaxis, your doctor may prescribe an injectable emergency medication called epinephrine. Epinephrine (EpiPen®) is usually given at the first sign of a severe allergic reaction, followed by emergency medical treatment. Your doctor will provide specific information about when and how you should use epinephrine.
- Omalizumab injection — This medication can treat allergic reactions and asthma attacks through an injection that can be administered in the hospital or at home.
Education to treat food allergies
Proper education and information about food allergies help people make smart decisions to avoid and manage their allergen(s).
This information may include:
- How to administer emergency medications.
- Recommendations for how you can prevent allergic reactions.
- The creation of an allergy action plan.
Living with a food allergy
Some other tips for managing a food allergy include:
- Carrying an EpiPen when leaving the house.
- Checking food labels and restaurant menus for your allergen.
- Cleaning surfaces before eating.
- Informing family, friends, and colleagues about your allergy and allergy action plan.
- Informing wait staff about your allergy.
