Introduction
Celiac disease is an autoimmune disorder triggered by the ingestion of gluten, a protein found in wheat, barley, and rye. For individuals with celiac disease, eating foods containing gluten damages the small intestine, leading to a wide range of symptoms, including diarrhea, fatigue, weight loss, bloating, gas, abdominal pain, nausea and vomiting, constipation, headaches and fatigue, irritability, anemia, joint pain, and brain fog. It can also lead to more serious complications if not managed or treated.
Approximately 1% of people are diagnosed with celiac disease (based on a combination of antibody testing and intestinal biopsy[1], but I recently noticed that I have been seeing more people with celiac disease in the last 5 years than in all the years since I first started in private practice. It wasn’t my imagination.
A 2023 study from Alberta reported that occurance of celiac disease rose more than 6.2% between 2015 and 2020, despite no change in the amount of antibody testing [2]. This was attributed to environmental factors, including viral infections, early exposure to antibiotics, and possibly, the introduction of large amounts of gluten in childhood [1].
How Common is Celiac Disease?
While only 1% of people are diagnosed with celiac disease [1], ~99% of people diagnosed carry one of the celiac disease–associated HLA genes. Only 30% of genetically predisposed people develop the disease [1].
The prevalence of celiac disease is slightly higher in females than males (0.6% vs 0.4%) and higher among children (0.9%) than adults (0.5%) [1].
First-degree relatives of those with celiac disease (i.e., parents, full siblings, and offspring) have an 11-15% risk of being diagnosed with celiac disease, while second-degree relatives (grandparents, aunts, uncles, and cousins) have lower rates of around 2% to 7% [1].
Coexisting Conditions
Compared to the general population, the prevalence of celiac disease is higher among people diagnosed with other autoimmune disorders, including type 1 diabetes (5% to 6%), Hashimoto thyroiditis (2% to 6%), and Sjögren syndrome (7%) [1].
The results of Celiac Canada’s 2024 State of Celiac Survey indicate that 16.8% were also diagnosed with thyroid disease, 10.5% with arthritis, 3.6% with Inflammatory Bowel Disease, 1.8% with type 1 diabetes, and 1.6% with Sjogren’s syndrome.
Time from Symptom Onset to Diagnosis
Celiac Canada’s 2024 State of Celiac Survey [3] results indicate that a significant number of respondents in Canada experience long delays from the time they first experienced symptoms until they were diagnosed.
- 7% waited 20 years or more
- 2% waited 10 years to < 20 years
- 9% waited 5 years to < 10 years
- 4% waited 2 years to < 5 years
- 4% waited 6 months to < 20 years
Furthermore, the longer the delay to diagnosis, the worse the perceived quality of life [3]. However, regardless of how long a delay there was before diagnosis, people reported a general improvement in quality of life after adopting a gluten-free diet, after diagnosis [3].
- A quarter of respondents in British Columbia and Saskatchewan reported a diagnostic delay of over 20 years [4].
- At least half the respondents in Quebec, Newfoundland & Labrador, and Ontario (52.6%) saw a Gastroenterologist before diagnosis, with 40–49% in all other provinces, except Saskatchewan at 38.5% [4].
Symptoms
Symptoms of untreated celiac disease can vary greatly from person to person. People may experience digestive symptoms such as abdominal pain, bloating, constipation, diarrhea, etc., but many experience symptoms that are not related to the digestive symptoms, such as anemia, low bone density, mouth ulcers, brain fog, fatigue, migraines, and joint pain. Others are asymptomatic and don’t experience any symptoms at all.
Dermatitis herpetiformis (DH) is celiac disease of the skin, and is characterized by blistering, intensely itchy skin. The rash has a symmetrical distribution and is most frequently found on elbows, knees, buttocks, back of the neck, scalp, and upper back. People with dermatitis herpetiformis can have gastrointestinal damage without obvious symptoms.
Celiac disease can be difficult to recognize since symptoms are often vague and nonspecific. Similarities between symptoms of celiac disease and other conditions often lead to a misdiagnosis of irritable bowel syndrome, lactose intolerance, chronic fatigue syndrome, or diverticulosis.
The results of Celiac Canada’s 2024 State of Celiac Survey [3] found that
- 7 % experienced bloating
- 9% experienced abdominal pain or discomfort
- 3% experienced gas/flatulence
- 4% experienced extreme weakness/tiredness
- 5% experienced loose stool
Gluten Reaction
Celiac disease is often misunderstood regarding the severity and duration of accidental gluten exposure. Celiac Canada’s 2024 State of Celiac Survey [3] found that most individuals are sick for more than a day after gluten exposure.
- The survey reported that most people reacted to consuming gluten within 3 hours (57.6%) or 12 hours (30.2%) [3].
- More than half of respondents experienced a reaction of at least one day or longer (57.1%) [3].
- Most people experienced a reaction lasting 3 to 24 hours (35.2% to 1-3 days (36.3%) [3].
Diagnosis
It is estimated that 1.4% of people are diagnosed with celiac disease based on serum antibody testing (e.g. IgAtTg tests) and 0.7% are confirmed by intestinal biopsy [1].
Screening
A simple blood screening test, tissue transglutaminase IgA (IgAtTg), is commonly used to screen for celiac disease, and an intestinal biopsy is currently considered the gold standard to confirm diagnosis [3]. A gluten-free diet must not be started before these blood tests are done, since it can interfere with diagnosis.
Biopsy
Small intestinal biopsies are the only definitive means of diagnosing celiac disease. A biopsy also provides a baseline score of the current damage to the small intestine [3].
The biopsy is performed by a specialist in the gastrointestinal field and is usually done on an outpatient basis, with sedation or an anesthetic often used. If you have been referred by your physician to see a gastroenterologist to have a small bowel biopsy, it is essential that a gluten-free diet not be started before the biopsies, since it can interfere with making an accurate diagnosis.
Reality of “Diagnosis”
The results of Celiac Canada’s 2024 State of Celiac Survey indicated that there is a relatively high rate of people being diagnosed only on the basis of an antibody blood test (19.2%) or on the basis of symptoms only (12.5%). Only 65.2 were diagnosed based on both abnormal blood tests and an intestinal biopsy [3].
Sources of Quality Information About a Gluten-free Diet
Celiac Canada’s 2024 State of Celiac Survey reported that
- 75% of people consulted their family doctor after diagnosis, but only 30% found them to be a good or excellent resource for following a gluten-free diet [3].
- Approximately 60% of people found their Gastroenterologist to be a good or excellent source of information for following a gluten-free diet [3] and their usefulness to be at the same rate as for Registered Dietitians [3].
The Role of a Dietitian in Celiac Disease
Dietitians play a key role in supporting individuals at all stages of a person’s diagnosis.
Diagnosis Process
Dietitians sometimes initiate the diagnosis process by requesting an IgAtTg test based on presenting symptoms, or when noticing low iron status in men (who don’t menstruate) or take medications that may underlie iron-deficient anemia.
After Diagnosis
Dietitians who are knowledgeable about celiac disease are able to provide nutrition education and counselling to translate complex nutritional information into personalized guidance adapted to each person’s cultural needs and lifestyle. Nutrition education includes the importance of following a gluten-free diet for life, guidance on identifying sources of gluten by reading labels on foods and medications, and avoiding gluten cross-contamination at home, at restaurants, and when visiting with friends.
Assessing and Addressing Nutrient Deficiencies
Untreated celiac disease can result in nutrient malabsorption because the intestine has become damaged before adopting a gluten-free diet. Dietitians can assess nutrient status by requesting specific lab work, then provide nutrition education to address deficiencies, and help people with celiac disease by designing a Meal Plan for them that targets ongoing malabsorption and increased nutrient needs.
Final Thoughts…
If you suspect that you may have celiac disease, I can provide you with a Lab Test Request Form to bring to your doctor or to a local or online walk-in clinic to have the IgA tTG screening blood test, before you stop eating gluten, as it is needed to ensure an accurate result. If the results come back positive, your doctor or the one at the walk-in clinic will likely refer you to a Gastroenterologist for further testing, and I can provide you with the most current Canadian recommendation from 2025 required to master a gluten-free lifestyle, from identifying hidden gluten in food labels and preventing cross-contamination at home, at restaurants, and when traveling that includes more than 25 pages of handouts to have as references.
Should you also have celiac-associated nutrient deficiencies, such as low iron or B12, I can help you address these so you can restore your energy and long-term health.
More Info
To learn about me here, and about the Celiac Disease Management Package that I offer.
To your good health.
Joy
You can follow me on:
Twitter: https://twitter.com/jyerdile
Facebook: https://www.facebook.com/BetterByDesignNutrition/
Support for Celiac Disease
I can help you get screened, and support you should you get a positive diagnosis.
Already diagnosed? I can help you implement a strategy to avoid exposure to gluten, reduce symptoms, and normalize your lab results.
References
- Diagnosis and management of celiac disease. Blom J-J, Gidrewicz D., Turner J et al, CMAJ Nov 2025, 197 (38) E1258-E1265; DOI: 10.1503/cmaj.230091
- King JA, Bakal JA, Li B, Whitten TA, et al, Variation in Testing for and Incidence of Celiac Autoimmunity in Canada: A Population-Based Study. Gastroenterology. 2023 Apr;164(4):567-578.e7. doi: 10.1053/j.gastro.2022.12.040. Epub 2023 Jan 10. PMID: 36634826.
- Celiac Canada, State of Celiac – 20 years after the first survey, what’s changed, May 3. 2024, https://e.issuu.com/embed.html
- Celiac Canada, 2024 State of Celiac Survey Results, February 2024, https://www.celiac.ca/state-of-celiac/
