Celiac Disease, Gluten Intolerance and Gluten Allergy: What’s the Difference?

First published October 2013
Updated December 2025

Many people hear the word “gluten” and think it can cause stomach problems or that it is unhealthy. While most can tolerate gluten without any issue, there are many in whom it does cause problems. Three common conditions where gluten causes issues are celiac disease, gluten intolerance (non-celiac gluten sensitivity), and gluten allergy. They may sound similar, but they are very different.

What Is Gluten?

Gluten is a protein found in grains such as wheat, barley, and rye. It helps hold dough together and can help bread stay chewy and soft. For these reasons, gluten is often added to other products to help them stick together. The word “gluten” comes from the Latin word for glue.

Celiac Disease

Celiac disease is an autoimmune disease. This means the body’s immune system attacks itself when gluten is ingested. When someone with celiac disease eats gluten, their immune system attacks the lining of their small intestine, causing damage. Over time, this damage to the intestine can make it hard to absorb nutrients like iron, vitamin D and calcium. These difficulties with absorption can lead to poor growth, weight loss, fatigue, stomach pain, and diarrhea, along with many other potential symptoms.

Celiac disease is not an allergy or an intolerance, but a true disease. The only treatment for celiac disease is to follow a gluten-free diet to help the intestine heal and prevent further damage. People with celiac disease do not always have symptoms right after eating gluten, but over time will usually have symptoms from their intestinal damage. There are specific blood tests to screen people for celiac disease and usually a biopsy of the small intestine is needed to confirm diagnosis.

Gluten Intolerance (Non-Celiac Gluten Sensitivity)

Gluten intolerance is a commonly used term and is different from celiac disease. Most importantly, people with gluten intolerance do not have damage to their intestines. Without intestinal damage, they do not have problems with absorption like people with celiac disease.

For someone with gluten intolerance, eating gluten can still make them feel sick. Symptoms are very similar to celiac disease including bloating, stomach pain, gas, diarrhea and “brain fog.” There are no clear tests for gluten intolerance. The diagnosis is often made when screening tests for celiac disease are normal in people with stomach problems after eating gluten. People with gluten intolerance often feel better when they remove gluten from their diet.

Gluten Allergy (Wheat Allergy)

A gluten allergy or wheat allergy is less common than celiac disease or gluten intolerance. This is a true food allergy that involves the immune system reacting quickly to eating gluten. Symptoms of gluten allergy include itching, hives, swelling of the lips or face, stomach pain, vomiting, or trouble breathing. People with a gluten or wheat allergy must also avoid eating wheat, but for different reasons than people with celiac disease or gluten intolerance.

Understanding the differences between these three issues is important. Celiac disease requires lifelong gluten avoidance to prevent intestinal damage and long-term health problems. Gluten intolerance is about preventing unpleasant symptoms, without worrying about long-term health effects. A gluten or wheat allergy is about avoiding foods to prevent allergic reactions.