Common Food Allergens: What You Need to Know

According to Food Allergy Research and Education (FARE), a nonprofit organization, an estimated 33 million Americans–including one in every 13 children–suffer from food allergies. And roughly 90% of potentially deadly reactions are caused by just a handful of specific ingredients. In this article, we’ll explore the 9 major food allergies that affect most sufferers, with insights from the Cleveland Clinic’s allergist and Associate Director of Food Allergy Center, Dr. Jaclyn Bjelac.

Major food allergies Identified by the FDA

1. Shellfish

Shellfish contain the #1 food allergen in the U.S., affecting approximately 8.4 million people. This allergy often starts in adulthood, with 60% of cases emerging around age 28. It causes a high incidence of severe and immediate reactions, including anaphylaxis or anaphylactic shock. Typically lifelong, this allergy can be triggered by:

• Crustaceans (shrimp, crab) 
• Mollusks (clams, oysters)

The primary allergens in shellfish are proteins called:

• Tropomyosin
• Arginine kinase
• Parvalbumin

Even being exposed to shellfish fumes during cooking can trigger a reaction if you’re highly allergic. So you’ll need to steer clear of any place they’re being prepared, as well as avoiding consumption. 

2. Fish

Fish allergies impact about 6.6 million people or 2.3% of the U.S. population–predominantly female adults. Occurrences are higher in areas like Scandinavia and Asia, where seafood is a dietary staple. Studies suggest if you’re allergic to one type of fish, such as salmon or tuna, you’re likely allergic to others due to the presence of parvalbumin, a protein in all finfish. Fish and shellfish are biologically different, so an allergy to one doesn’t necessarily indicate an allergy to the other. 

3. Peanuts

Peanuts are the third most common food allergen in the U.S., affecting around 1-2% of the population–over 6 million Americans. Despite its prevalence and severity, research suggests about 22% of sufferers outgrow their peanut allergy by age 20.The chance of outgrowing a peanut allergy depends on the initial level of sensitivity. Those with lower levels of a type of antibody called peanut-specific IgE are more likely to enter remission. People with only skin-related symptoms (i.e. rash) are also more likely to outgrow it.A family history of peanut allergies can increase your risk. However, research suggests introducing a child to peanuts early in life could potentially reduce it. 

4. Tree nuts

Unlike peanuts–which are legumes–tree nuts are true nuts that grow on trees. Common examples include:

• Walnuts
• Almonds
• Hazelnuts
• Pecans
• Cashews
• Pistachios

Roughly 1.1% of the U.S. population suffers from a tree nut allergy, and these numbers have been rising over recent decades.Tree nut allergies are a leading cause of food-allergy-related emergency room visits–and are usually lifelong. Only approximately 10% of those affected outgrow this allergy.Some research indicates 50% of children who are allergic to one tree nut also suffer reactions to others. However, one study found many people can tolerate certain nuts while being allergic to others. If you suffer from this allergy, check labels carefully. Be on the lookout for tree nuts in items you might not suspect, such as:

• Baked goods
• Candies
• Pesto
• Barbeque sauce

5. Milk

Another of the 9 major food allergens is milk, which triggers symptoms in about 4.7% of the U.S. population. This is the most common food allergy among infants and young children, affecting between 1.8% and 7.5%. Most children develop this allergy before age one. And while experts previously thought most would outgrow it before school age, recent studies suggest fewer than 20% do by age 4. However, approximately 80% outgrow their milk allergy by age 16.For others, this allergy can be lifelong–or may not develop until adulthood. It may require you to avoid all dairy products, including:

• Butter
• Cheese
• Yogurt

However, research shows some people (75% of children) can tolerate baked goods containing milk. This is because the baking process denatures milk’s proteins, reducing allergenic properties.If you’ve been diagnosed with a milk allergy, consult your doctor to determine whether you need to avoid dairy entirely.

Difference between milk allergy and lactose intolerance

It’s important to note that a milk allergy is very different from lactose intolerance–and the former can be far more severe. Lactose intolerance is a digestive issue resulting from a lack of enzymes that process milk sugar, leading to symptoms like nausea and diarrhea. It isn’t life-threatening. A milk allergy, on the other hand, triggers a serious immune response that can range from rashes to life-threatening airway swelling, Dr. Bjelac says.

6. Eggs

0.9% of all U.S. children and 1.3% of those under five suffer from this major food allergy. Interestingly, African American children–who constitute 13.2% of the U.S. pediatric population–represent 23.4% of those with an egg allergy. About 70% of affected children outgrow egg allergies by age 16. This allergy is less common in adults, affecting only 0.6%.Some people are only allergic to either egg whites or yolks because they contain different proteins. Among sufferers, egg white allergies are more common.If you’re allergic, eggs can be challenging to avoid, as they’re often hidden in foods like:

• Breads 
• Cakes
• Pasta
• Breaded, fried foods
• Condiments including mayonnaise
• Even some drinks, such as protein shakes

However, you may not need to avoid the above foods as long as they’ve been cooked. One study found that nearly two-thirds of children with an egg allergy could tolerate baked eggs (as in bread or cakes), as there may be a decrease in allergenicity due to the cooking process. Consult an allergist to determine whether you can safely introduce foods containing cooked eggs into your diet. 

7. Wheat

Wheat allergies are more common in younger populations than adults, affecting up to 1% of U.S. children. Most kids outgrow this allergy by age 12–although, for some, it’s lifelong.Wheat allergies involve an immune system reaction to any of the four proteins found in wheat, which include:

• Albumin
• Globulin
• Gliadin
• Gluten

This sets it apart from celiac disease and non-celiac gluten sensitivity (NCGS). 

Wheat allergy vs. celiac disease vs NCGS

Celiac disease is an autoimmune disorder in which only the protein, gluten, triggers damage to the small intestine. NCGS is less well-understood, but research shows it causes similar symptoms to celiac disease without harming the intestines.Unlike those with celiac disease or NCGS, people with a wheat allergy may only need to avoid wheat, not all gluten-containing grains. But this depends on your specific allergies.Avoiding wheat can be a challenge, since it’s found in many prepared foods, including:

• Baked goods 
• Breakfast cereals 
• Beer
• Even condiments like soy sauce

However, in recent years, there’s been a rise in wheat-related health concerns, making alternative types of bread, pasta, and even beer available at thousands of grocery stores, worldwide. Look for products made with grains like: 

• Amaranth
• Rice
• Quinoa
• Oats
• Sorghum 

8. Soybean

While less common than other food allergies, soy allergies are still prevalent. They affect approximately 0.4% of children and 0.3% of adults. Most children outgrow this allergy before age 10. And most also react to peanuts, as both soy and peanuts are legumes.Avoiding soy can be challenging due to its widespread use in processed foods. However, Dr. Bjelac says many people with a soy allergy can tolerate processed soy-based products like soy flour and soy milk, which contain less allergens.Consult an allergist to determine which soy-containing products you can safely enjoy.  

9. Sesame

The final major food allergen is sesame, which has spawned a rising risk of severe reactions like anaphylaxis in recent years. Approximately 0.2% of both children and adults in the U.S. are allergic to this seed–a number that’s comparable to soy and pistachio allergies.Avoiding sesame isn’t as simple as staying away from sesame seed buns, either. This seed is a common component in numerous prepared foods, including hummus. If you’re allergic to sesame, check labels carefully. And consult your doctor to determine which packaged foods are safe for you.

Symptoms of a food allergy

Symptoms of food allergies vary widely from person to person, but they might include:

• Itchy skin or hives
• Swelling of the lips, cheeks, or eyes
• Coughing, wheezing, or breathlessness
• Hoarse voice or noisy breathing
• Nasal itching or congestion
• Sneezing
• Nausea, vomiting, or abdominal pain
• Diarrhea
• Dizziness 

In severe cases, anaphylaxis can occur–which may be life-threatening. Its symptoms include: 

• Difficulty breathing 
• Swelling in the throat
• Rapid heart rate 
• Sudden low blood pressure
• Fainting

These symptoms can arise within minutes or be delayed for several hours. If you notice any of these signs, seek medical attention immediately.

Natural treatment for food allergies

Typically, treatment for food allergy is strictly avoiding the offending food or ingredient. However, recent research supports the use of oral immunotherapy (OIT). OIT involves gradually exposing the immune system (via ingestion) to increasing doses of the allergen to desensitize the body over time.Consult with your doctor to determine whether allergen avoidance or immunotherapy is the best strategy for managing your allergies.Recognizing the top 9 food allergens can help you take control of your health–especially if you’re experiencing symptoms. If you’re allergic to any of these foods, work with your healthcare provider to determine the best strategy and eating plan. You can still enjoy a diverse diet filled with delicious and nutritious options while remaining healthy and reaction-free. References:Facts and Statistics – FoodAllergy.orgFood Allergies | FDAThe US population-level burden of cow’s milk allergy – PMCMilk Allergy – an overview | ScienceDirect TopicsChildren with Delayed-Type Cow’s Milk Protein Allergy May Be at a Significant Risk of Developing Immediate Allergic Reactions Upon Re-introduction – PMCMilk Allergy | Causes, Symptoms & Treatment | ACAAI Public WebsiteModulation of Milk Allergenicity by Baking Milk in Foods: A Proteomic Investigation – PMCLactose Intolerance – StatPearls – NCBI BookshelfFood allergy: immune mechanisms, diagnosis and immunotherapy – PMCEgg Allergy in US Children – PMCEgg Allergy: Diagnosis and Immunotherapy – PMCThe natural history of egg allergyAdult onset egg allergy: a case reportRecent advances in the management of nut allergy – ScienceDirectNew onset egg allergy in an adultPeanut-Induced Anaphylaxis in Children: A Literature Review – PMC.Current Controversies and Future Prospects for Peanut Allergy Prevention, Diagnosis and Therapies – PMCPeanut Allergy: New Advances and Ongoing ControversiesThe global burden of illness of peanut allergy: A comprehensive literature review – PMCThe natural history of peanut allergyWhite paper on peanut allergy – part 1: Epidemiology, burden of disease, health economic aspects – PMCPrevalence of peanut and tree nut allergy in the US determined by a random digit dial telephone surveyIdentification of cross-reactive allergens in cashew- and pistachio-allergic children during oral immunotherapy. – PMCAccidental Reactions to Foods: Frequency, Causes, and Severity – PMCFood Allergy – PMCShellfish Allergy – StatPearls – NCBI BookshelfSeafood allergy: A comprehensive review of fish and shellfish allergensPrevalence and Characteristics of Shellfish Allergy in the Pediatric Population of the United StatesAllergens and molecular diagnostics of shellfish allergy – PMCInfluence of Lifestyle and Dietary Habits on the Prevalence of Food Allergies: A Scoping Review – PMCAdult seafood allergy in the Texas Medical Center: A 13-year experience – PMCAllergens and molecular diagnostics of shellfish allergy – PMCWhat Do We Know Now about IgE-Mediated Wheat Allergy in Children? – PMCWorld Agricultural ProductionWheat Allergy in Children: A Comprehensive Update – PMCPathogenesis of Celiac Disease and Other Gluten Related Disorders in Wheat and Strategies for Mitigating Them – PMCRecent advances in understanding non-celiac gluten sensitivity – PMCA Meta-Analysis of the Prevalence of Wheat Allergy Worldwide – PMCCeliac DiseaseAssociation Between Celiac Disease and Mortality Risk in a Swedish Population | Gastroenterology | JAMAAllergen immunotherapy for food allergy: Evidence and outlook – PMCFood Allergy from Infancy through Adulthood – PMCThe Natural History and Risk Factors for the Development of Food Allergies in Children and Adults – PMCThe natural history of soy allergyThe population threshold for soy as an allergenic food – Why did the Reference Dose decrease in VITAL 3.0? – ScienceDirectPrevalence and Severity of Sesame Allergy in the United States – PMCThe Global Rise and the Complexity of Sesame Allergy: Prime Time to Regulate Sesame in the United States of America?Vegan diets from an allergy point of view – Position paper of the DGAKI working group on food allergyAllergic to Sesame? Food Labels Now Must List Sesame as an Allergen | FDAOral immunotherapy for food allergy: Translation from studies to clinical practice? – PMCOral Immunotherapy for Food-Allergic Children: A Pro-Con Debate – PMCFood Allergy and Intolerance: A Narrative Review on Nutritional Concerns – PMCParvalbumin: A Major Fish Allergen and a Forensically Relevant Marker – PMC.