Common food allergies and how to manage them
While any food can potentially trigger an allergic reaction, the most common food allergies are caused by eight specific foods. These are also known as the major allergens. This article provides useful information about some of the most common food allergies, how to manage them, and how allergies are diagnosed.
Table of Contents
- Understanding food allergies
- The most common food allergies
- Allergy testing
- Living with food allergies
Understanding food allergies
An allergy is an overreaction of the immune system to a substance that is harmless for most people. When someone is allergic to a certain food, the body’s immune system identifies the proteins in that food as harmful and attacks them. This reaction can lead to a variety of symptoms, ranging from mild to severe (NHS, 2021). During an allergic reaction, allergen-specific IgE antibodies trigger the release of chemicals in the body, causing allergy symptoms such as swelling, itching, breathing difficulties, and hives.
It is estimated that the lifetime prevalence of food allergies in Europe ranges between 0.1% and 6.0% of the population (Nwaru et al., 2014). However, prevalence can vary greatly depending on geographic region and is influenced by factors such as genetics and environmental exposure. Food allergies are more common in children than in adults, and many food allergies resolve on their own during childhood. An estimated six to eight percent of children and three percent of adults have a food allergy (Mayo Clinic, 2021).
The most common food allergies
The most common food allergens include peanuts, milk, eggs, fish, shellfish, wheat, soy, and tree nuts. These eight foods are responsible for about 90% of all food allergies (FDA, 2023). Read on to learn more about the eight most common food allergens.
Peanut allergy
Peanut allergies are among the most common food allergies, especially in children, and they often persist for life (FARE, 2021). Peanuts are not the same as tree nuts (e.g., almonds, cashews, or walnuts), as peanuts actually belong to the legume family. Allergic reactions to peanuts can cause severe and potentially life-threatening anaphylaxis. Symptoms include rashes, swelling of the face and airways, and digestive problems. Avoiding peanuts and peanut-containing products is essential for managing this allergy, and people with peanut allergies should always carry an epinephrine injector (EpiPen) in case of anaphylaxis.
Milk allergy
Milk allergy is an immune response to the proteins in cow’s milk. It is one of the most common allergies in children, affecting around 2–3% of children under the age of three (FARE, 2021). While up to 75% of children outgrow a milk allergy, it remains one of the most common food allergies in adults. Symptoms can range from mild reactions such as hives and digestive issues to severe symptoms such as anaphylaxis.
Importantly, milk allergy must be distinguished from lactose intolerance, in which the body lacks the enzyme needed to digest lactose, a sugar found in milk. Although both conditions can lead to digestive discomfort after consuming milk, a milk allergy can provoke a severe, life-threatening reaction, which is not the case with lactose intolerance. Moreover, people with lactose intolerance may be able to consume lactose-free dairy products or take lactase supplements, whereas individuals with a milk allergy must completely avoid the allergen.
Egg allergy
Another common allergy is egg allergy, especially among children, although many outgrow it by adolescence (ACAAI, 2021). Egg allergies can cause symptoms such as rashes, shortness of breath, and stomach pain, up to severe anaphylaxis. People allergic to chicken eggs may also react to other types of eggs, such as duck and quail eggs.
People with an egg allergy are often advised to avoid eggs entirely. However, this can be challenging, as eggs are a hidden ingredient in many foods. Special caution is needed with products that may contain traces of egg, such as certain baked goods, salad dressings, or processed foods. Some vaccines can also contain egg proteins, including yellow fever, rabies, and flu vaccines (Bradley, 2022). If you have an egg allergy, speak to your doctor about which vaccines are safe for you to receive.
Fish allergy
Fish allergies are allergic reactions to finned fish such as cod, halibut, tuna, or salmon. This allergy typically appears in adulthood and can trigger severe reactions (FARE, 2021). Symptoms usually occur within minutes to up to two hours after consuming fish and may include skin reactions, vomiting, digestive problems, breathing difficulties, and anaphylaxis. For people with a fish allergy, it is important to avoid all types of fish unless a doctor confirms that certain types are safe to eat.
Fish and shellfish are not closely related, and having a fish allergy does not necessarily mean one must avoid shellfish. However, it is important to avoid cross-contamination between fish and shellfish.
Shellfish allergy
Shellfish allergy refers to an allergic reaction to crustaceans (shrimp, lobster, and crab) or mollusks (scallops, oysters, clams, and mussels) (ACAAI, 2019). Crustaceans are responsible for most allergic reactions, and some individuals with a shellfish allergy can eat mollusks without having a reaction. However, this should be confirmed by an allergist before consuming shellfish, and care should be taken to avoid cross-contamination between different types of shellfish.
The symptoms of a shellfish allergy can range from mild (hives and/or vomiting) to severe (anaphylaxis). This allergy is usually lifelong, and the best approach is to avoid shellfish completely.
Wheat allergy
A wheat allergy is an immune response to one of the proteins found in wheat. This allergy commonly occurs in children but can also affect adults. The most frequent symptoms of wheat allergy include rashes, nausea, headaches, breathing difficulties, and, in rare cases, anaphylaxis. Most children with wheat allergies outgrow them by adulthood—about 65% of children with wheat allergies overcome them by the age of 12 (ACAAI, 2021).
It is important to note that wheat allergy is different from celiac disease, an autoimmune disorder triggered by gluten, and from non-celiac gluten sensitivity. Non-celiac gluten sensitivity causes digestive problems after consuming gluten but does not involve an immune response. With a wheat allergy, the allergen must be completely avoided. This requires awareness of which foods contain wheat or may have been processed in facilities where cross-contamination with wheat could occur. Although many foods contain wheat (including bread, cookies, pasta, and other wheat-based products), it is possible to substitute wheat products with other grains such as rice, quinoa, and oats.
Soy allergy
Soy allergies are a common food allergy among children and are usually outgrown by adulthood (ACAAI, 2019). Symptoms of a soy allergy include irritation of the skin and mucous membranes, vomiting, diarrhea, wheezing, and in rare cases, anaphylaxis. Soy is found in many foods, including processed foods, Asian cuisine, and infant formulas, making label reading essential for people with this allergy. Individuals with a soy allergy can often tolerate soy derivatives, including highly refined soybean oil and soy lecithin. Speak to your allergist to determine whether it is safe for you to consume these products (ACAAI, 2019).
Tree nut allergy
Tree nut allergies are allergies to all types of tree nuts, including walnuts, almonds, hazelnuts, pecans, cashews, and pistachios. This allergy is different from a peanut allergy, as peanuts are legumes related to beans and soy. Tree nut allergies are common in both children and adults and are usually lifelong (FARE, 2022). About 50% of people who are allergic to one type of tree nut are also allergic to other tree nuts.
People with a tree nut allergy are at risk of life-threatening anaphylaxis. It is important to avoid all types of tree nuts and their products, and to carry an epinephrine injector if you have a tree nut allergy.
Allergy Testing
When treating a food allergy, it is essential to identify the triggers of your symptoms. There are various types of allergy tests, including skin prick tests, blood tests, and elimination diets.
In a skin prick test, a small amount of the suspected allergen is applied to the skin and then lightly pricked with a tiny lancet. If a wheal (a small red bump) forms, this indicates a possible allergy. This test must be conducted under medical supervision, as there is a risk of a severe allergic reaction. Skin prick tests are considered a reliable indicator of allergies, but they may not be suitable for certain individuals due to the skin irritation they cause.
Blood tests, also known as IgE tests, measure the level of specific IgE antibodies in the blood in response to individual allergens. This test can be performed either in a doctor’s office or at home. The advantage of this test is that there is no risk of an allergic reaction. However, additional confirmation tests may be required for a definitive allergy diagnosis.
An elimination diet involves removing suspected foods from the diet for a period of time and then gradually reintroducing them to identify which ones cause symptoms. An elimination diet may be recommended by your doctor if your allergy is known not to cause severe symptoms such as anaphylaxis.
Another form of allergy testing is the oral food challenge, which is considered the most accurate method for diagnosing food allergies. Under close medical supervision, patients consume the suspected food in gradually increasing amounts to determine whether an allergic reaction occurs (AAAI, 2020).
Would you like to check your body’s reaction to more than 295 allergens, including all common food allergens? The Extensive Allergy Test from Homed-IQ is an IgE blood test that can be taken from home. After collecting your blood sample, you send it to our certified laboratory for analysis. The comprehensive lab report provides information about your body’s reactivity to each allergen, which you can share with your doctor for further evaluation and treatment.
Living with Food Allergies
Living with food allergies can be challenging, but with the right tools and strategies, individuals can lead a full and healthy life. Avoiding the allergen is the most important step in managing food allergies (Mayo Clinic, 2021). This includes carefully reading food labels and asking about ingredients when eating out. It is also important to inform family, friends, and coworkers or school staff about your allergies so they can help prevent exposure.
In many countries, it is legally required that common food allergens be clearly labeled on a food product’s ingredient list. Additionally, it must be stated whether the food was produced in a facility where cross-contamination may have occurred. New regulations on allergen labeling in foods are crucial for preventing accidental ingestion of allergens and potentially fatal allergic reactions.
Carrying an epinephrine auto-injector (EpiPen) is essential for individuals with severe allergies to treat potential anaphylaxis (Mayo Clinic, 2021). Milder symptoms can often be treated with antihistamines. Regular check-ups with a healthcare provider are also recommended to monitor food allergies, especially in children, who may outgrow their allergies over time. While living with food allergies requires vigilance, with the right approach they can be effectively managed, allowing for a healthy and fulfilling life.
