Wheat Allergy vs. Gluten Intolerance vs. Celiac Disease: What's the Difference?
Wheat Allergy vs. Gluten Intolerance vs. Celiac Disease: What's the Difference?
After reading my recent blogs about food allergies versus food intolerances and lactose intolerance versus a dairy allergy, I figured I would cover another topic that causes a lot of confusion: wheat, gluten, and celiac disease.
People often use these terms interchangeably, but they are not the same thing.
One is a food allergy.
One is considered a food sensitivity or intolerance.
One is an autoimmune disease.
Although they may involve many of the same foods, they have different causes, symptoms, diagnostic methods, and long-term implications.
So, I want to clear up the confusion.
First, A Quick Refresher
In my previous blog, I explained the difference between a food allergy and a food intolerance.
A food allergy involves the immune system. The body mistakenly identifies a food protein as harmful and launches an immune response. Reactions can range from mild to life-threatening.
A food intolerance does not involve the immune system. Instead, the body has difficulty processing or tolerating a particular food or food component. Symptoms are usually related to the digestive system and, while uncomfortable, are generally not life-threatening.
Then there is celiac disease, which is neither an allergy nor an intolerance.
Frequently Asked Questions
Is gluten intolerance the same as celiac disease?
No. Gluten intolerance, or non-celiac gluten sensitivity, does not cause the autoimmune damage to the small intestine seen in celiac disease. Although the symptoms may overlap, they are different conditions with different long-term health implications.
Can you have a wheat allergy but not react to gluten?
Yes. A wheat allergy is a reaction to one or more proteins found in wheat. Gluten is just one of those proteins. Someone with a wheat allergy may react to wheat but tolerate other gluten-containing grains, depending on their specific allergy.
Can adults develop celiac disease?
Yes. Although celiac disease is often diagnosed during childhood, it can develop or be diagnosed at any age.
Should I stop eating gluten before being tested for celiac disease?
No. Removing gluten before testing can lead to inaccurate results. If you think you may have celiac disease, talk with your healthcare provider before making changes to your diet.
Celiac disease is an autoimmune disease. When someone with celiac disease eats gluten, their immune system attacks the lining of the small intestine, leading to inflammation and damage.
Although all three conditions may require avoiding certain foods, the reasons for doing so differ greatly.
At a Glance
First, let’s do an overview of these three conditions.
Wheat Allergy:
Cause: Immune system Allergy
Trigger: Wheat protein
Immune system involved? Yes
Can it be life-threatening? Yes
Primary treatment: Avoid wheat (not gluten)
Gluten Intolerance (Non-Celiac Gluten Sensitivity)
Cause: Not fully understood
Trigger: Gluten
Immune system involved? No
Can it be life-threatening? No
Primary treatment: Limit or avoid gluten as tolerated
Celiac Disease
Cause: Autoimmune disease
Trigger: Gluten
Immune system involved? Yes
Can it be life-threatening? No immediate allergic reaction, but serious long-term consequences if untreated
Primary treatment: Strict lifelong gluten-free diet
What Is a Wheat Allergy?
A wheat allergy occurs when the immune system reacts to one or more proteins naturally found in wheat.
Many people mistakenly think someone with a wheat allergy is allergic to gluten, but gluten is only one of many proteins found in wheat. The immune system may react to gluten, albumins, globulins, or other wheat proteins. And, people with a wheat allergy can potentially eat rye and barley since those are not wheat.
Symptoms often develop within minutes to a few hours after exposure and may include:
Hives
Itching
Swelling of the lips, tongue, or throat
Nasal congestion
Wheezing
Difficulty breathing
Nausea or vomiting
Abdominal pain
Diarrhea
Dizziness
Anaphylaxis
The severity varies from person to person.
Some individuals may experience relatively mild reactions.
Others may react to very small amounts of wheat, or even to wheat flour, in the air.
For example, someone working in a commercial bakery or pizza shop where flour is constantly airborne may develop symptoms simply from inhaling wheat flour.
Others only react after eating wheat-containing foods.
Because reactions can be unpredictable, wheat allergies should always be taken seriously.
Foods That May Contain Wheat
Obvious sources include:
Bread
Pasta
Crackers
Cookies
Cakes
Tortillas made with wheat flour
Cereals
Less obvious sources may include:
Soy sauce
Gravies
Breaded meats
Soup mixes
Salad dressings
Seasoning blends
Some candies
Processed foods
Reading ingredient labels carefully is essential.
How Is Wheat Allergy Diagnosed?
Diagnosis usually begins with a medical history and symptom review.
An allergist may recommend:
Skin prick testing
Blood tests measuring allergy antibodies (IgE)
Oral food challenge under medical supervision, when appropriate
Many children with wheat allergy eventually outgrow it, although some continue to have it into adulthood.
Adults can also develop a wheat allergy later in life, although this is less common.
What Is Gluten Intolerance?
You may also hear the term non-celiac gluten sensitivity (NCGS).
Unlike a wheat allergy, gluten intolerance is not an allergy.
Unlike celiac disease, it is not an autoimmune disease.
Researchers are still learning exactly why some people develop symptoms after eating gluten despite testing negative for both wheat allergy and celiac disease.
Symptoms vary but commonly include:
Bloating
Gas
Abdominal pain
Diarrhea
Constipation
Fatigue
Brain fog
Headaches
Joint discomfort
These symptoms can significantly affect quality of life, but they generally do not cause permanent damage to the intestine.
Foods That Contain Gluten
Gluten is found naturally in:
Wheat
Barley
Rye
Foods containing these grains include:
Bread
Pasta
Pizza
Crackers
Cereals
Pretzels
Baked goods
Gluten can also be found in:
Soy sauce
Malt flavoring
Some soups
Gravies
Salad dressings
Beer
Some processed foods
How Is Gluten Intolerance Diagnosed?
There is currently no single test that confirms gluten intolerance.
Instead, healthcare providers first rule out:
Wheat allergy
Celiac disease
If both conditions are excluded and symptoms improve after removing gluten and return when gluten is reintroduced, non-celiac gluten sensitivity may be diagnosed.
Gluten intolerance can develop during adulthood, and symptoms may change over time.
What Is Celiac Disease?
Celiac disease is an autoimmune disease.
When someone with celiac disease eats gluten, the immune system attacks the villi, the tiny finger-like projections lining the small intestine that help absorb nutrients.
Over time, this damage can interfere with nutrient absorption and increase the risk of several health problems.
Unlike a food allergy, celiac disease does not usually cause an immediate allergic reaction.
Instead, repeated exposure to gluten continues to damage the small intestine, even if symptoms seem mild.
Symptoms may include:
Chronic diarrhea
Constipation
Abdominal pain
Bloating
Weight loss
Fatigue
Iron deficiency anemia
Mouth sores
Osteoporosis
Delayed growth in children
Skin rash called dermatitis herpetiformis
Some people have very few digestive symptoms and are diagnosed because of anemia, osteoporosis, infertility, or abnormal blood work.
How Is Celiac Disease Diagnosed?
One of the most important things to know is this:
Do not start a gluten-free diet before being tested.
Removing gluten before testing can make the results inaccurate.
Diagnosis usually includes:
Blood tests looking for antibodies, such as tissue transglutaminase (tTG-IgA)
Additional blood tests when appropriate
Small intestinal biopsy during an upper endoscopy to confirm the diagnosis
Unlike wheat allergy, celiac disease is lifelong.
There is currently no cure.
The treatment is a strict, lifelong gluten-free diet.
Although celiac disease is often diagnosed during childhood, it can develop and be diagnosed at any age.
There Is No Such Thing as a "Gluten Allergy"
This is another common misconception.
People often say they have a gluten allergy.
Medically speaking, gluten allergy is not a recognized diagnosis.
If someone reacts to gluten, they may have:
Celiac disease
Non-celiac gluten sensitivity
If they have an allergy, it is typically a wheat allergy, not a gluten allergy.
Using the correct terminology helps everyone better understand the condition and reduces confusion.
What About Oats?
Oats are naturally gluten-free.
However, many oats are processed in facilities that also process wheat, barley, or rye, creating a risk of cross-contact.
For individuals with celiac disease, choosing oats labeled certified gluten-free is generally recommended.
A small percentage of people with celiac disease may still react to a protein in oats called avenin, so discuss oat consumption with your healthcare provider if symptoms continue.
Can You Drink Beer or Distilled Spirits?
This is a question I hear fairly often.
Traditional beer is usually made from barley, wheat, or both, which means it contains gluten.
People with celiac disease should avoid traditional beer unless it is specifically labeled gluten-free.
Gluten-reduced beers are different from gluten-free beers and may not be appropriate for everyone with celiac disease.
Distilled spirits are a little different.
According to organizations such as the Celiac Disease Foundation, the distillation process removes gluten proteins. As a result, plain distilled spirits are generally considered gluten-free, even when they are made from wheat, barley, or rye.
However, flavored spirits or products with ingredients added after distillation may contain gluten, so it's important to check the label if you have celiac disease or gluten sensitivity.
Someone with a wheat allergy should discuss alcohol choices with their allergist, since individual recommendations may vary depending on their allergy and how the product is manufactured.
What About Bakeries and Pizza Shops?
People often wonder whether simply walking into a bakery is dangerous.
The answer depends on the condition.
For someone with a severe wheat allergy, airborne wheat flour can trigger symptoms, particularly in commercial bakeries or pizza shops where flour is regularly mixed and dispersed into the air.
For someone with celiac disease, the concern is usually not brief exposure to airborne flour. The greater concern is cross-contact, where flour settles on surfaces, utensils, or food and is accidentally ingested.
Either way, individuals with these conditions should discuss their specific circumstances with their healthcare provider and follow individualized recommendations.
The Bottom Line
Although wheat allergy, gluten intolerance, and celiac disease are often discussed together, they are very different conditions.
A wheat allergy is an immune system reaction to wheat proteins.
Gluten intolerance is a condition in which gluten triggers symptoms without an allergy or autoimmune disease.
Celiac disease is an autoimmune disease in which gluten causes damage to the small intestine.
Understanding these differences can help you avoid unnecessary dietary restrictions, seek the right medical evaluation, and better support family members, friends, or coworkers who live with these conditions.
When it comes to food-related health conditions, using the correct terminology really does matter.
More Reading
Additional Resources
For more information, visit:
Celiac Disease Foundation: https://celiac.org
Food Allergy Research & Education (FARE): https://www.foodallergy.org
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): https://www.niddk.nih.gov
