A Dietitian Explains Gluten Intolerance in Simple Terms

Certain grains, including wheat, barley, and rye, naturally have gluten.

In addition, food manufacturers and drug companies may add gluten to make processed foods and medications. (1)

Gluten is even found in some cosmetics. (2)

A reaction to gluten is rare, but the symptoms can be severe. And sometimes, doctors have trouble diagnosing gluten intolerance.

Here is some background on the health issues related to gluten and what you can do if you think it’s causing a problem for you.

Gluten Intolerance vs. Celiac Disease

They may seem like the same thing, but gluten intolerance and celiac disease are two separate issues.

Experts estimate that 6 percent of people in the United States are intolerant to gluten, but only 1 percent has celiac, making non-celiac gluten intolera­nce six times more common. (2)

Celiac disease is an autoimmune condition where the body mistakes gluten for a threat (like a virus).

After gluten exposure, people with celiac disease have an inflammatory response that can damage the small intestine. This damage makes it difficult for the body to absorb nutrients.

If left untreated, celiac disease can cause malnutrition and weight loss. (3)

During celiac disease, the immune system makes antibodies that can be measured in the bloodstream. There are also specific genes related to celiac disease, unlike in gluten intolerance. (2)

In non-celiac gluten intolerance (or “gluten sensitivity”) contact with gluten leads to unpleasant symptoms. These can include:

• Bloating and gas
• Brain fog
• Depression
• Fatigue
• Headaches
• Joint pain
• Leg numbness
• Muscle cramps
• Nausea
• Skin rashes

The most frequently reported intestinal symptoms of non-celiac gluten intolerance are bloating, gas, stomach pain, and diarrhea. Other common symptoms include feeling tired, anxious, or having a headache. (4)

Symptoms can last for days after eating gluten, making a gluten sensitivity difficult to diagnose. (2)

Many of the symptoms match those experienced with celiac, minus the genetic factors and antibody response. (1)

It’s a good idea to ask your healthcare provider about testing to rule out celiac disease first before assuming you have a gluten intolerance.

Causes of Non-Celiac Gluten Sensitivity

The exact cause of non-celiac gluten sensitivity is unknown.

There’s speculation that an imbalance or disruption of natural gut bacteria leads to gluten intolerance. (5)

Researchers suspect that many cases of gluten intolerance go undiagnosed. (4)

Studies suggest that gluten intolerance is likely related to immune system issues. Gluten intolerance is associated with several autoimmune conditions, including psoriasis, rheumatologic diseases, and Hashimoto thyroiditis (hypothyroidism). (6)

Symptoms of non-celiac gluten sensitivity, including leg numbness, headache, fatigue, and chronic pain, are also common in fibromyalgia and irritable bowel syndrome (IBS), leading some researchers to believe there may be a link among these conditions. (6)

Additionally, people with IBS or fibromyalgia sometimes report improvements after sticking to a gluten-free diet.

Researchers have also pointed to potential connections between gluten and various brain issues, including depression, autism, peripheral neuropathy, schizophrenia, anxiety, and ataxia (loss of coordination). (6)

While scientists have yet to make any definitive conclusions, gluten intolerance is a growing area of interest.

Could I Be Allergic to Gluten?

There is no such thing as a gluten allergy, but you can have a wheat allergy. A gluten allergy is a misleading term, which likely refers to celiac disease or a wheat allergy.

With celiac disease or wheat allergy, coming in contact with the trigger (gluten or wheat) prompts an abnormal immune response with symptoms to follow. (7)

You’re more likely to have a food allergy if you or your relatives have asthma, eczema, or hay fever. Usually, children are diagnosed with wheat allergies, but fortunately, 65 percent outgrow them by age 12. (7)

Wheat allergy symptoms may include:

• Asthma
• Headaches
• Hives
• Stuffy or runny nose, sneezing
• Vomiting and diarrhea

During a severe allergic reaction, your airways may become blocked, sending your body into a state of shock known as anaphylaxis.

This life-threatening condition requires immediate medical attention. People with an allergy may need to carry a prescription epi-pen for accidental exposures.

Your doctor may also recommend antihistamines or corticosteroids to help keep your allergy under control. (7)

How to Test for Gluten Intolerance

There’s no specific test for gluten intolerance, so getting the right diagnosis can be tricky.

The first step is meeting with your healthcare provider to discuss your symptoms and medical history.

While you’re still eating gluten, they’ll take blood and skin tests to screen for a gluten allergy and celiac disease.

A chance of a false negative test is high if you are not consuming gluten daily for at least 6 weeks before a test. (2)

Once your provider rules out these other gluten-related conditions, they’ll have you follow a strict gluten-free diet. (2)

You may need to meet with a dietitian to learn how to avoid gluten.

It’s also important to keep track of any changes to your symptoms. Writing in a journal will help you stay on track and reflect on how you’re feeling.

After following a gluten-free diet for at least six weeks, you’ll experiment with adding gluten back in. If your symptoms return, there’s a good chance you are gluten intolerant. (2)

However, if this approach doesn’t affect your symptoms, you may be dealing with another type of food intolerance or health issue.

Continue meeting with a gastroenterologist (digestive health specialist) and dietitian to reveal the underlying problem.

Contrary to recent food trends, needlessly following a gluten-free diet can negatively impact the quality of your diet, especially when you don’t need to. (4)

Not only are gluten-free products more expensive, but they also tend to lack key micronutrients, like iron, B12, calcium, zinc, magnesium, folate, and vitamin D. (4)

If you’re required to stay on a gluten-free diet for life, work with a dietitian to help cover any nutritional gaps with the right foods and possibly supplements.

Sorting out your symptoms can take time, so it’s crucial to be patient, communicate with your healthcare team, and advocate for yourself to figure out what’s going on with your body.

Non-celiac gluten intolerance is still a relatively young area of research, so there’s a good chance more information will become available as new studies are conducted. (4)

Gluten Intolerance Treatment Options

If a gluten-free diet relieves your symptoms, you might need to stick with it for life. (2)

Connecting with others who face similar challenges, either through a support group or online community, can help you cope and get helpful tips on maintaining a gluten-free lifestyle.

Although going gluten-free can feel restrictive, learning new recipes can help.

Many grocery stores and food manufacturers offer gluten-free products.

Additionally, there’s a wide array of naturally gluten-free foods:

• Fruits
• Vegetables
• Beans
• Lentils
• Chickpeas
• Dairy
• Meat
• Nuts
• Seeds
• Eggs
• Soy
• Grains, like rice and quinoa

Getting plenty of variety in your diet is essential to avoid missing out on critical nutrients when you’re on a gluten-free diet. (8)

One of the challenges of a gluten-free diet is getting enough fiber since you won’t be eating whole wheat products. (8)

Safe high-fiber foods you can add to your diet include:

• Beans
• Berries
• Brown rice
• Buckwheat
• Chia seeds
• Corn
• Lentils
• Millet
• Nuts
• Pears
• Vegetables

Oats are naturally gluten-free. However, many oatmeal products you can purchase in the store are processed in a facility with other grains, making them a potential source of cross-contamination. (9)

Always check the food label and look for products intended specifically for people who can’t have gluten.

In addition to avoiding gluten, some healthcare providers also recommend taking probiotics and digestive enzymes to boost your ability to digest and tolerate gluten. (2)

Research on supplements for gluten intolerance is still inconclusive, but you may find it helpful to explore these types of products with your provider.

How to Avoid Exposure to Gluten

Depending on your level of gluten sensitivity, avoiding gluten can be tough.

Aside from the obvious offenders, like wheat bread and pasta, traces of gluten may sneak in while you’re preparing food or through non-food products.

Potential sources of cross-contamination include:

• Air fryers
• Cutting boards
• Deep fryers
• Toasters and toaster ovens
• Utensils
• Strainers

Since these items can be hard to clean thoroughly, some people with severe gluten intolerance need to use separate kitchen equipment from others in their household. (3)

Aside from food, gluten may also be hidden in products you may not expect — such as lipstick, medications, vitamins, and toothpaste. (10)

Contact the company that produces the item to ask about their manufacturing processes when in doubt. You should be able to find a phone number or email address to get in touch with a company representative by looking on the business website.

What to Do After an Accidental Gluten Exposure

Even the most cautious gluten avoiders may unknowingly contact gluten on occasion.

Despite label reading, sometimes companies change how they make products, meaning things that used to be gluten-free are a source of cross-contamination or direct exposure. (10)

Since there’s no medication or short-term remedies for gluten intolerance, you’ll want to focus on strategies to alleviate your symptoms.

If you have diarrhea or stomach pain, drink plenty of water and try small, bland meals (just as you might do if you have a stomach bug).

If you feel nauseous, peppermint or ginger tea can help to soothe your stomach. (10)

Digestive enzymes may also be helpful.

Excessive vomiting or diarrhea can lead to dehydration and electrolyte imbalances. (2)

If you’re unable to keep food and water down, or you feel sick for several days in a row, reach out to your healthcare provider. Feeling weak, fainting, or having a high fever could signal that it’s time to seek medical attention.

As you resume a gluten-free diet and stay away from triggers, you should start to feel like yourself again.

The Bottom Line

Gluten is a protein that can stir up unpleasant symptoms in people with celiac disease or gluten sensitivities.

If your doctor rules out those conditions and gluten still seems to be a problem, you may have gluten intolerance.

Unfortunately, getting diagnosed with gluten intolerance isn’t always straightforward.

You can start by undergoing a few basic tests at your doctor’s office to rule out other health issues and pin down the correct diagnosis.

Following a gluten-free diet and watching out for gluten-containing products is the best way to put gluten intolerance symptoms to rest. (8)

Although it may seem like a big adjustment at first, your healthcare team can help guide you on the ins and outs of a gluten-free lifestyle.