Food Allergy vs. Intolerance: What’s the Difference?

It’s common to hear people say they’re “allergic” to a certain food, but in many cases, what they’re actually experiencing is a food intolerance. While both can cause uncomfortable symptoms, food allergies and food intolerances are very different. 

Our expert team at Advanced ENT & Allergy in Newport News, Virginia, led by Timothy Queen, MD, and Erica Cherry, FNP-BC, explains how food allergies and intolerance affect the body, how serious they can be, and how they’re managed.

Understanding food allergies

A food allergy involves the immune system. When someone with a food allergy eats even a small amount of the trigger food, their immune system mistakenly identifies it as harmful and releases chemicals like histamine to protect the body. This reaction can happen quickly and may be severe or even life-threatening.

Common symptoms of a food allergy include hives, swelling of the lips or throat, difficulty breathing, vomiting, and, in serious cases, anaphylaxis. Anaphylaxis is a medical emergency that requires immediate treatment, often with an epinephrine injection.

Common food allergens

The most common food allergens include:

• Peanuts
• Tree nuts
• Milk
• Eggs
• Wheat
• Soy
• Fish
• Shellfish

For individuals with true food allergies, strict avoidance is essential, and reading food labels carefully becomes part of daily life.

Understanding food intolerances

A food intolerance doesn’t involve the immune system. Instead, it typically affects the digestive system and occurs when the body has difficulty breaking down certain foods. 

One of the most well-known examples is lactose intolerance, where the body lacks enough of the enzyme lactase to properly digest dairy products.

Food intolerance symptoms

Symptoms of a food intolerance are usually less severe than those of an allergy and tend to develop more gradually. They may include:

• Bloating
• Gas
• Stomach cramps
• Diarrhea
• Headaches

While uncomfortable, food intolerances aren’t generally life-threatening. Many people with intolerances can still eat small amounts of the offending food without serious consequences.

How they’re diagnosed

Another key difference lies in diagnosis. Food allergies are often diagnosed through skin prick tests, blood tests, or supervised food challenges conducted by one of our allergists. 

Food intolerances, however, can be harder to pinpoint and are often identified through elimination diets and tracking symptoms over time.

Why understanding the differences matters

Understanding the difference between a food allergy and a food intolerance is important for both safety and quality of life. Mislabeling a food intolerance as an allergy can lead to unnecessary dietary restrictions, while overlooking a true allergy can put someone at risk for a serious reaction.

If you suspect that a certain food is causing symptoms, it’s best to consult with our team. We can give you a proper evaluation to help determine the cause. We can also guide you toward the safest and most effective way to manage your diet.

To learn more, book a consultation at Advanced ENT & Allergy today. Call us at 757-979-6475 or click here to request an appointment online.