Celiac disease is an autoimmune condition where eating gluten (found in wheat, barley, and rye) triggers damage to the small intestine. About 1 in 100 people in the U.S. have celiac disease, but up to 97% remain undiagnosed. Many experience vague symptoms, and the average time to diagnosis is about nine years.

In people with celiac disease, gluten causes the immune system to attack the lining of the small intestine, damaging structures called villi that absorb nutrients. This can lead to widespread nutritional deficiencies and other complications if not treated with a strict gluten-free diet.

The Link Between Celiac Disease and Type 1 Diabetes

Celiac disease and type 1 diabetes are both autoimmune disorders that share genetic risk factors, especially the HLA-DQ2 and HLA-DQ8 genes. These conditions frequently occur together:

Up to 10% of people with type 1 diabetes also have celiac disease, compared to just 1% in the general population.
People with one autoimmune condition are at a higher risk of developing another, such as autoimmune thyroid disease or Sjögren’s syndrome.

The American Diabetes Association recommends routine screening for celiac disease in all patients with type 1 diabetes, starting at diagnosis and repeating every few years, even if symptoms are mild or absent.

Symptoms: Classic, Silent, and Everything In Between

Celiac disease can range from obvious symptoms to silent damage with no noticeable signs. People may experience:

Gastrointestinal Symptoms

Bloating, cramping, or gas
Diarrhea or constipation
Nausea or stomach pain

Non-Gastrointestinal Symptoms

Fatigue, irritability, or depression
Headaches or joint pain
Itchy skin (dermatitis herpetiformis)
Iron-deficiency anemia
Weak bones (osteopenia or osteoporosis)

People with type 1 diabetes and undiagnosed celiac may have unexplained hypoglycemia, erratic glucose readings, or poor growth in children.

Diagnosing Celiac Disease in People with Diabetes

Diagnosis usually involves two key steps:

1. Blood Tests

Serologic testing looks for antibodies against gluten, including:

Tissue transglutaminase IgA (tTG-IgA)
Endomysial antibodies (EMA)
Total IgA levels (to rule out IgA deficiency)

These tests are highly sensitive and specific, but must be done while eating gluten for accurate results.

2. Intestinal Biopsy

If blood tests are positive, an upper endoscopy with biopsy confirms the diagnosis. This allows doctors to see the damage to the villi and rule out other conditions. Though invasive, this is the gold standard for diagnosis.

⚠️ A gluten-free diet should not be started before testing, as it may cause false negatives.

Why Diagnosis Matters

Left untreated, celiac disease can lead to:

Malnutrition
Growth delays
Osteoporosis
Infertility
Peripheral neuropathy
Rarely, certain cancers like intestinal lymphoma

In people with type 1 diabetes, undiagnosed celiac disease may worsen glycemic control, increase the risk of complications, and cause nutrient malabsorption that affects insulin needs.

Lifelong Treatment: The Gluten-Free Diet

A confirmed diagnosis means a strict gluten-free diet for life. This involves avoiding:

All wheat, rye, and barley products
Foods made in facilities with cross-contamination
Many processed foods, sauces, and additives contain gluten

For people with diabetes, following a gluten-free diet presents unique challenges:

Gluten-free products often have different glycemic loads, affecting blood sugar
Accurate carbohydrate counting may require extra care
Fiber, iron, calcium, and B vitamins may be harder to get from a gluten-free diet

A registered dietitian can help you balance diabetes care with a safe, gluten-free diet.

Clinical Resources and Research

American Diabetes Association: Standards of Care – Screening for Celiac
Celiac Disease Foundation – Symptoms and Diagnosis
Clinical Trial: Gut Microbiome and Autoimmune Conditions (NCT04864020)
Leonard MM, Sapone A, Catassi C, Fasano A. Celiac disease and diabetes: the genetic and autoimmune connection. Trends Endocrinol Metab. 2019.

Final Thoughts

Celiac disease and type 1 diabetes often travel together. If you or your child has type 1 diabetes, regular screening for celiac—even without symptoms—is key to early detection. A confirmed diagnosis empowers you to take action and avoid serious complications.

Living with both conditions can be challenging, but with the proper support, a balanced gluten-free diet, and reasonable blood sugar control are possible.

Celiac Disease can lead to serious health complications.