The 8 most common food allergies
By Sanjay “Jay” Patel, D.O. | Allergy & Immunology Apr 14, 2023 • 8 min
Millions of Americans have one or more food allergies that might cause anything from hives to a life-threatening reaction. It’s important to be aware of the most common food allergies and the symptoms they can produce.
What is an allergen?
Your body’s immune system keeps you healthy by fighting off substances that can harm you, such as certain types of harmful viruses and bacteria. If you have a food allergy, your immune system identifies protein in a certain food as a danger and reacts in order to protect you. The substance in the food that triggers the reaction is an allergen.
Most people need to eat the food in question in order to have an allergic reaction. However, some people are highly sensitive to the food they’re allergic to and can have a reaction simply from breathing in the allergen or touching the food item with their skin.
What is the difference between an allergy and a sensitivity to food?
Many people lump food allergies and sensitivities together. However, these terms don’t mean the same thing.
A food sensitivity or an intolerance causes less serious symptoms than a food allergy and typically only affects the digestive system. You may also have a medical condition that can interfere with digestion, like irritable bowel syndrome. People with lactose intolerance lack an enzyme that breaks down lactose sugar in milk, so they may experience gas, diarrhea and other digestive issues when they consume food containing lactose.
Food allergies occur due to an immune system response. Consuming or coming in contact with even a small amount of a food that your body considers an allergen can result in severe symptoms.
Understanding the difference between a food intolerance and a food allergy is very important.
What are the most common allergens in food?
Many foods are known to be allergens. However, nine out of 10 allergic reactions to foods involve one of the following eight food allergies:
- Shellfish, like crab, shrimp and lobster
- Finned fish, like flounder, cod and bass
- Tree nuts, like pecans, walnuts and almonds
Under the Food Allergen Labeling and Consumer Protection Act of 2004, food manufacturers must identify these eight foods on ingredient labels. The law also requires them to note any ingredients that are derived from a common allergen. However, there are some limitations. Poultry, most meats, some egg products and alcoholic beverages may not contain these warnings.
You can be allergic to foods other than the eight most common. However, the law only requires that common food allergens to be called out on food labels. If you’re allergic to an uncommon food, read ingredient lists carefully beforehand to help avoid an allergic reaction.
What are some food allergy symptoms?
Most people develop symptoms within a few minutes to four to six hours after eating a food they’re allergic to. These symptoms can include:
- Hives or an itchy rash
- Pale, flushed or blue-colored skin
- Stomach cramps, diarrhea or vomiting
- Repetitive cough
- Stuffy, itchy or runny nose or sneezing
- Itchy or watery eyes
- Tight or itchy feeling in the mouth
- Trouble swallowing
- Swelling of the face, tongue, throat or lips
- Shortness of breath, wheezing or trouble breathing
- Weak pulse
- Loss of consciousness
- Anaphylaxis. This life-threatening reaction sends your body into shock. It can cause trouble with breathing, a sudden drop in blood pressure and other symptoms. Call 911 right away if you have signs of anaphylaxis.
Food allergy symptoms can change over time. You could experience only a minor food skin allergy symptom like a rash, hives or itchy throat the first time you eat a food but then later experience a more severe reaction the next time you eat or come in contact with the same food. This makes it important to read labels and strictly avoid any food item that you’re allergic to, regardless of how mild or severe a past reaction was.
Food allergy symptoms can also begin at any time. You could suddenly start experiencing an allergic reaction to a food that never caused you trouble before. However, this isn’t common.
Some food allergies may go away on their own. This is most common when the allergies start during childhood. It’s less common for people to outgrow allergies to tree nuts, peanuts, fish and shellfish. These types of allergies are more likely to last a lifetime.
How do you treat food allergies?
The treatment of food allergies usually centers on avoiding the foods that trigger reactions. There is no cure for food allergies. However, your healthcare provider may recommend that you carry an epinephrine pen, or EpiPen, in case you accidentally come into contact with an allergen. Epinephrine is the only treatment that stops anaphylaxis, and when administered quickly, it can save your life.
To treat hives and other minor reactions, your healthcare provider may recommend other medications, such as a prescription or over-the-counter antihistamines. In some cases, to reduce swelling, a corticosteroid may be administered as an injection, cream, or pill.
Is there a home test for food allergies?
There isn’t an FDA-approved home test for food allergies. While you may find kits that advertise testing for food sensitivities, these tests aren’t the same as the food allergy testing performed by an allergy specialist.
Undergoing an allergy test for food is important if you suspect you may be allergic. Talk to your healthcare provider about your concerns. They can determine what type of testing, such as blood work or a skin test, may be helpful for you. If you’re not sure what food may be causing the allergic reaction, your provider may have you keep a food journal to record everything you eat and any symptoms you experience. If you’re diagnosed with a food allergy, your healthcare provider can talk to you about emergency treatments and share tips on how best to prevent reactions or manage your symptoms.
Updated April 2023.