Food Allergy VS. Food Intolerance

With the ever growing attention around food quality these days and the dissection of how it affects our bodies, it is no wonder that food allergies and intolerance are a hot topic. For that reason, it is also no surprise that many people often confuse food allergies with food intolerance. While they both cause similar signs and symptoms, they are very different. Food allergies involve the immune system, whereas a food intolerance (with the exception of celiac disease) involves the digestive system.

According to the Center for Disease Control and Prevention (CDCP), food allergies affect about 2% of adults and 4-8% of children in the United States, and the number of young people with food allergies has increased over the last decade.

Food allergy:

In Food allergy, the immune system identifies the allergens as harmful pathogens; the immune system then produces antibodies called Immunoglobulin E (IgE). The antibodies attach to the cells causing them to release chemicals like histamine in the body. These chemicals are responsible for the symptoms.

The eight major food allergens identified by low:

  • Milk

  • Eggs

  • Fish (e.g., bass, flounder, cod)

  • Crustacean shellfish (e.g., crab, lobster, shrimp)

  • Tree nuts (e.g., almonds, walnuts, pecans)

  • Peanuts

  • Wheat

  • Soybeans

These eight foods and any ingredients that contain protein derives from one of them, are designated as (major food allergens) by the Food Allergen Labeling and Customer Protection Act (FALCPA).

There is no cure for food allergies. Strict avoidance of food allergens and early recognition and management of allergic reaction to food, are important measures to prevent serious health consequences, According to the FDA.

Food intolerance:

Food intolerance on the other hand is a chemical reaction occurs when you are unable to breakdown a substance in certain foods; this could be due to lack of enzymes, sensitivity to food additives, or certain chemicals that are naturally found in some foods.

Foods that tend to cause intolerance:

  • Dairy products

  • Chocolate

  • Flavor enhancer such as MSG

  • Food additives

  • Strawberries, citrus fruits and tomatoes

  • Wine

  • Histamine and other amines in some foods


Sometimes it can be difficult to differentiate between the symptoms of food allergy and food intolerance. Usually with a food allergy, the symptoms can develop soon after consuming or coming in contact with the food, while in food intolerance the symptoms may develop soon but they may take up to 12 to 24 hours to develop.

In case of food allergy even the smallest amount of the food can trigger the immune system resulting in symptoms, while in food intolerance the symptoms may not occur until consuming a certain amount of food. Unlike a food intolerance, food allergies can cause serious, sometimes life threatening reaction that needs medical attention, called (anaphylaxis).

According to the national institute of allergy and infectious diseases (NIAID), if you are allergic to a certain type of food you may experience some or more of the following symptoms

  • Itching in your mouth or swelling

  • GI symptoms, such as vomiting, diarrhea, or abdominal cramps and pain

  • Hives or eczema

  • Tightening of the throat and trouble breathing

  • Drop in blood pressure

Symptoms of food intolerance are usually mild and not life threatening. People with food intolerance may experience some or more of the following symptoms:

  • Nausea

  • Stomach pain

  • Gas, cramps or bloating

  • Vomiting

  • Diarrhea

  • Headaches

  • Irritability or nervousness


Written By: Sara Hamdan, RD-To-Be & our NYNG star intern




National Institute of Allergy and Infectious Disease (NIAID)

U.S Food and Drugs Administration (FDA)

Food Standers Agency (FSA)

Food Allergy Research and Education (FARE)

Allergy UK

Food Allergen Labeling and Customer Protection Act (FALCPA)

Center of Disease Control and Prevention (CDCP)

Nick VanMeter