Food Allergies Guide: Symptoms, Management & Living Safely

Overview

A food allergy is an immune system reaction that occurs when your body mistakenly identifies a specific food protein as a harmful invader. This triggers the release of chemicals like histamine, which cause symptoms that can range from mild discomfort to life-threatening anaphylaxis. Food allergies are distinct from food intolerances (such as lactose intolerance), which do not involve the immune system and are rarely dangerous. An estimated 32 million Americans have a food allergy, including 1 in 13 children, per the non-profit Food Allergy Research & Education (FARE).

Signs & Symptoms

Symptoms of a food allergy usually appear within minutes to 2 hours of eating the trigger food, and can vary in severity from person to person, and even from one reaction to the next for the same person. Mild symptoms include tingling or itching in the mouth, hives, itchy skin, and mild swelling of the lips, tongue, or face. Severe symptoms include trouble breathing, wheezing, throat tightness, rapid or weak pulse, dizziness, fainting, and a drop in blood pressure.

Causes & Risk Factors

The most common food allergens, known as the "Big 9," account for 90% of all allergic reactions: milk, eggs, peanuts, tree nuts, soy, wheat, fish, shellfish, and sesame. The exact cause of food allergies is not fully understood, but several risk factors increase your likelihood of developing one.

• Family history of food allergies or other allergic conditions (eczema, asthma, hay fever)
• Personal history of other allergies or asthma
• Being a child (most food allergies develop in childhood, though adult-onset allergies are increasingly common; many children outgrow milk, egg, and wheat allergies by age 5, but peanut, tree nut, fish, and shellfish allergies are often lifelong)
• Delayed introduction of common allergenic foods in infancy (current pediatric guidelines recommend introducing allergenic foods early to reduce allergy risk)

Diagnosis

Never attempt to self-diagnose a food allergy, as symptoms can overlap with other conditions. Your healthcare provider will start with a detailed history of your symptoms, timing relative to meals, and suspected trigger foods. They may order one or more of the following tests to confirm a diagnosis:

Treatment & Management

There is no cure for most food allergies, so the cornerstone of management is strict avoidance of the confirmed trigger food. In the U.S., the Food Allergen Labeling and Consumer Protection Act requires all packaged foods to clearly list the 9 major allergens on their ingredient labels, making it easier to identify unsafe products. If you have a diagnosed food allergy, your provider will likely prescribe an epinephrine auto-injector to carry with you at all times to treat severe reactions.

• Read all ingredient labels on packaged foods every time you buy them, as ingredients and manufacturing processes can change
• Ask detailed questions about ingredients and cross-contamination risks when eating at restaurants or at someone else’s home
• Carry your epinephrine auto-injector with you at all times, and teach friends, family, and coworkers how to use it in case of an emergency
• Wear a medical alert bracelet that lists your food allergies
• Work with your provider to create a written emergency action plan, and share it with people close to you

Living With It

Adjusting to life with a food allergy can feel overwhelming at first, but with planning, you can safely enjoy meals, social events, and travel. Connect with support groups for people with food allergies to share tips and resources, and work with a registered dietitian to ensure you get all the nutrients you need while avoiding trigger foods. Many restaurants now offer dedicated allergen-friendly menus, and a wide range of pre-made, certified allergen-free products are available in most major grocery stores. Be sure to wash hands, utensils, and cooking surfaces thoroughly before preparing food, and avoid sharing food, drinks, or utensils to reduce the risk of cross-contamination.