Going gluten-free has become popular among people who are looking to improve their health. While those who have celiac disease, for example, must avoid gluten, others choose to forgo foods that contain gluten, too — perhaps unnecessarily.

Does it make sense for people who have type 1 or type 2 diabetes to go gluten-free? 

In this article we’ll do a deeper dive into gluten: What it is, where it’s found, signs and symptoms of gluten-related issues, and what the research says about gluten and diabetes.

Key Points:

  • People with type 1 diabetes are at a higher risk for celiac disease, an autoimmune condition in which gluten — a protein found in many grain foods — damages the small intestine. 
  • The American Diabetes Association (ADA) recommends screening for those with type 1 diabetes who have symptoms suggestive of celiac.
  • Unlike celiac disease, gluten sensitivity does not damage the small intestine but may cause similar symptoms. A gluten-free diet can alleviate symptoms for those with this sensitivity.
  • There is no substantial evidence to suggest that a gluten-free diet benefits people with type 2 diabetes unless they have celiac disease or gluten sensitivity.
  • For those without celiac disease, gluten sensitivity, or wheat allergy, unnecessarily avoiding gluten can lead to a deficiency in essential nutrients provided by whole grains, potentially impacting overall health negatively.

What is gluten?

According to the Celiac Disease Foundation, “Gluten is a general name for the proteins found in wheat, rye, barley, and triticale — a cross between wheat and rye.” Gluten provides elasticity to dough, helping it to rise and keep its shape during baking. The two main proteins found in gluten are called gliadin and glutenin. 

What foods contain gluten?

Gluten is found in foods made from wheat, barley, rye, and triticale, or that contain ingredients made from these grains. Note that there are different types of wheat, as well, including wheat berries, durum, emmer, farro, graham, semolina, and spelt.

Some commonly eaten foods that have gluten are:

  • Wheat-based foods: Bread, cereal, pasta, couscous, flour tortillas, crackers, cakes, cookies, pastries, seitan, and wheat gluten.
  • Rye: Rye bread, rye crackers, and some cereals (for example, Eden Organic Rye Flakes).
  • Barley: Malt, malt extract, malted milk, malt vinegar, some beer, soups that contain barley, brewer’s yeast.

Besides these foods, gluten is found in many ingredients and additives. For example, colorings, flavorings, starches, and thickeners may be made with grains that contain gluten. These ingredients are added to processed foods, such as sauces, gravies, soups, salad dressings, hot dogs, ice cream, and candy. 

What about oats? Oats are naturally gluten-free; however, they may become cross-contaminated if they are grown near or are processed in the same facility as wheat, rye, or barley. If you need to avoid gluten, look for oats that are labeled as being gluten-free.

What is celiac disease?

Celiac disease is a chronic digestive and autoimmune disorder that damages the lining of the small intestine. This disease is triggered by eating foods that contain gluten. Celiac disease is very serious, as it hinders the body from absorbing nutrients from food, and can lead to many serious health conditions, including:

  • Malnutrition
  • Anemia
  • Vitamin and mineral deficiencies
  • Heart disease
  • Liver damage
  • Osteoporosis (weak and brittle bones)
  • Nervous system problems (headaches, balance problems, peripheral neuropathy)
  • Reproductive problems (miscarriage, infertility)

Rarely, celiac disease may lead to small intestine cancer and non-Hodgkin’s lymphoma.

Celiac disease affects an estimated two million people in the United States — as many as 1 in every 133 Americans. Many people who have this condition have not been diagnosed. 

Symptoms of celiac disease

The symptoms of celiac disease can vary widely, and they may come and go. Digestive symptoms are common, and may include:

  • Bloating
  • Chronic diarrhea
  • Gas
  • Constipation
  • Pale, bad-smelling stool
  • Lactose intolerance
  • Nausea and vomiting
  • Stomach pain

But symptoms aren’t limited to the digestive tract. Some people with celiac disease may not have digestive symptoms, but may present with:

  • Fatigue
  • Joint or bone pain
  • Weight loss
  • Depression and anxiety
  • Mouth symptoms (dry mouth, canker sores)
  • Dermatitis herpetiformis (itchy rash with blisters)
  • Numbness and tingling in the legs

How is celiac disease diagnosed and treated?

Celiac disease is usually diagnosed through a combination of a medical history, physical exam, blood tests, and biopsies of the small intestine.

Blood tests are used to look for antibodies that are produced by the immune system in response to gluten; they’re also used to check for health problems that could be related to celiac disease, such as iron deficiency anemia. 

In some cases, blood samples or swabs to collect cells from the inside of the check are done to look for certain genetic variants called DQ2 and DQ8. Having these genetic markers signals an increased risk of celiac disease, although testing for them does not confirm a diagnosis of this condition. 

The “gold standard” for diagnosing celiac disease is a biopsy of the small intestine during an upper GI endoscopy, says the Celiac Disease Foundation. Samples of the small intestinal lining are then studied under a microscope to look for damage and inflammation caused by celiac disease. 

If celiac disease is confirmed, the treatment is adherence to a strict gluten-free diet to heal the lining of the small intestine. 

A gluten-free diet means avoiding all foods and non-food products, such as some medications, supplements, personal health products, and cosmetics, that contain gluten. Carefully reading product labels and ingredient lists is essential. 

There are no medications that treat celiac disease, and currently, there is no cure. 

What is gluten sensitivity?

Gluten sensitivity (also called non-celiac gluten sensitivity or gluten intolerance) is not the same as celiac disease. While both conditions involve problems with gluten and can cause digestive symptoms, gluten sensitivity is not an autoimmune condition, nor does it cause damage to the small intestine.

There is no diagnostic test for gluten sensitivity, but rather, it is determined based on symptoms and a negative diagnosis of celiac disease and wheat allergy.

Not all health experts agree that gluten is the culprit for gluten sensitivity symptoms. It’s possible, for example, that non-gluten components of wheat, such as fermentable, poorly absorbed short-chain carbohydrates (fermentable oligo-, di-, and monosaccharides and polyols, or FODMAPS, for short) could be the cause.

Symptoms of gluten sensitivity 

Gluten sensitivity symptoms can vary from person to person, but the most common symptoms are stomach pain, bloating, and/or changes in bowel patterns, according to the American Academy of Allergy, Asthma & Immunology (AAAI). Some people have other symptoms, such as:

  • Fatigue and weakness
  • Headaches
  • Joint or muscle pain
  • Skin problems
  • “Brain fog” (difficulty concentrating or memory problems)
  • Numbness or tingling in the hands or feet

It’s important to inform your healthcare provider if you have any of the above symptoms so that you can be tested and receive a proper diagnosis and treatment. A gluten-free diet may be helpful in providing symptom-relief, and/or possibly a low-FODMAP diet.

Is gluten harmful to people who don’t have celiac disease or gluten sensitivity?

Celebrities, athletes, social media influencers — and even some healthcare professionals — proclaim the benefits of a gluten-free diet, yet the reality is that many of these benefits are without merit.

One small study involving adults without known disorders compared a high-gluten diet with a low-gluten diet. The low-gluten diet led to moderate changes in the microbiome and led to improvements in self-reported bloating; however, the researchers attribute that to changes in dietary fiber intake. 

If you don’t have celiac disease, gluten sensitivity, or a wheat allergy, there is no conclusive evidence that ingesting gluten is harmful. The gut microbiome is actively being researched and while gluten may impact the microbiome, the bottom line is that further studies are needed. 

For people without celiac disease, gluten sensitivity, or a wheat allergy, gluten doesn’t damage your digestive tract. A gluten-free diet is not necessarily healthier than a diet containing gluten, nor does it necessarily lead to weight loss. 

Eliminating healthy gluten-containing foods from your diet could mean that you miss out on healthful whole grains, fiber, and vitamins and minerals. And many processed gluten-free foods are high in calories, sugar, fat, and sodium, which can lead to weight gain, fluctuations in blood sugars, and high blood pressure.

If you’d like more information about a gluten-free diet — for any reason — talk with a registered dietitian (RD).

What is the research on gluten and type 1 diabetes?

Most of the research on gluten and diabetes relates to type 1 diabetes. This is because type 1 diabetes and celiac disease share certain genetic markers. 

Environmental factors also play a role: Introducing gluten-containing foods to an infant’s diet and viral infections have been implicated as potential triggers for both celiac disease and type 1 diabetes.

Like celiac disease, type 1 diabetes is an autoimmune disorder characterized by the destruction of beta cells (the cells that produce insulin) in the pancreas. People with type 1 diabetes have a higher risk of developing other autoimmune disorders, and that includes celiac disease. 

Celiac disease affects about 1 percent of the worldwide population, but it can affect approximately 5 percent of people with type 1 diabetes, according to a study published in the March 2022 issue of the journal Cureus. Other studies suggest that the prevalence may be higher.

Because people with type 1 diabetes are at increased risk for celiac disease, the ADA recommends that adults with type 1 diabetes be screened for celiac disease “in the presence of gastrointestinal symptoms, signs, laboratory manifestations, or clinical suspicion suggestive of celiac disease.”

What is the research on gluten and type 2 diabetes?

When it comes to type 2 diabetes, the connection between gluten and celiac disease isn’t as strong. This may be because type 2 diabetes typically develops due to a combination of genetic, lifestyle, and environmental factors, whereas type 1 diabetes and celiac disease are both autoimmune conditions. 

Research linking gluten with a higher risk of type 2 diabetes is somewhat conflicting. Here are a few studies that have explored the possibility that a gluten-free diet may lower the risk of type 2 diabetes:

  • A study published in 2021 suggests that gluten-containing foods may influence the composition and function of the gut microbiota in the context of metabolic disorders such as type 2 diabetes. 
  • A review study published in 2018 concluded that “the evidence for an alleviating effect of a gluten-free diet is more uncertain, especially regarding the few human studies that have been conducted.” The authors go on to mention that animal studies report improvements in both obesity and type 2 diabetes with a gluten-free diet, but few studies with humans have been done.

But there is some evidence that a gluten-containing diet may actually lower the risk of type 2 diabetes:

  • According to a study published in 2018 in the journal Diabetologia, in three large prospective cohort studies of American men and women, higher gluten intake was associated with a lower risk of type 2 diabetes during 20 to 28 years of follow-up. The authors of the study concluded that “gluten intake at the consumption level typically seen in western populations is not a risk factor for type 2 diabetes.”

Clearly, more research is needed to better understand the relationship between gluten-containing foods and type 2 diabetes risk. 

Final thoughts

If you have diabetes, either type 1 or type 2, should you avoid eating gluten?

  • For type 1 diabetes: If you have symptoms that could suggest celiac disease or gluten sensitivity, first talk with your healthcare provider to determine if you should undergo testing. Depending on the outcome, you may need to follow a gluten-free diet if you have celiac disease; if you don’t have celiac disease but possibly have gluten sensitivity, it may be helpful to try a gluten-free diet for symptom relief.
  • For type 2 diabetes or risk for type 2 diabetes: There’s currently no good evidence to support following a gluten-free diet. Of course, let your provider know if you have symptoms that suggest celiac disease or gluten sensitivity — and remember that those symptoms could be related to other conditions, as well.
  • For the general population: For those without celiac disease, gluten sensitivity, or wheat allergy, eliminating gluten from the diet is unlikely to provide health benefits and may lead to missing out on important nutrients found in whole grains.

If you need or decide to follow a gluten-free diet, consult with a registered dietitian, ideally one who has experience with celiac disease and gluten sensitivity. Keep in mind that not all gluten-free foods are healthy, as many of them are higher in carbohydrate, fat, and sodium than the “regular” versions.

Finally, if gluten is not a concern for you, focus on choosing whole-grain, less-refined carbohydrate foods in place of highly processed, refined carbs. These foods, overall, are better for your blood sugars, weight, blood pressure, and gut health, and may help lower your risk of some chronic diseases.

Are you following a gluten-free diet? Try some of our delicious gluten-free recipes.