
Celiac Disease vs IBS
What is the Difference and How Does Diet Play a Role?
In Canada, it is estimated that nearly 1% of the population (or 1 in 114 Canadians) are affected by celiac disease1, while irritable bowel syndrome (IBS) is thought to affect up to 18% of the Canadian population – having one of the highest prevalence of IBS in the world. 2 Celiac disease and irritable bowel syndrome (IBS) can cause many of the same symptoms. Knowing the similarities and differences between the two is important if you hope to achieve an accurate diagnosis and an effective treatment plan.
What is Celiac Disease?
Celiac disease is a digestive condition that affects the small intestinal tract in the gut. If you have celiac disease, eating gluten damages the small intestinal villi, which are finger-like projections that capture nutrients from your food. This damage can cause both digestive and non-digestive symptoms.
Celiac disease is diagnosed by a blood test looking at tissue transglutaminase IgA antibody, and IgA antibody, followed by biopsy of the small intestine to confirm diagnosis. It is important to know that gluten must be consumed in adequate amounts prior to testing; removing gluten from your diet prior to proper work up may result in a false negative diagnosis. Once diagnosis is confirmed, your doctor will recommend the only current treatment for celiac, a life-long, gluten free diet.
What is Irritable Bowel Syndrome (IBS)?
Irritable bowel syndrome (IBS) is a functional gut disorder that affects the lower portion of the gastrointestinal tract, which includes the small and large intestines. There is nothing structurally wrong with the gut, but rather, there’s something wrong with how the gut moves and senses digestion. This can lead to symptoms of bloating, abdominal pain, and changes in bowel habits like constipation, diarrhea, or both.
There is no laboratory test that can confirm irritable bowel syndrome. Rather, structural conditions are ruled out, including but not limited to celiac disease, inflammatory bowel disease, and colorectal cancer, followed by confirming you meet the diagnostic criteria.
The diagnostic criteria for IBS includes having symptoms of recurrent abdominal pain at least one day per week for the last 3 months associated with at least two of the following:
- The pain is related to having a bowel movement
- Associated with a change in stool frequency
- Associated with a change in stool form/appearance
Further to this, IBS can be subtyped into diarrhea dominant (IBS-D), constipation dominant (IBS-C), or a mix (IBS-M), depending on symptoms.
While there is no diagnostic testing for IBS, what is important to know is, it is a real condition with real options for management, including diet.
Similarities and Differences in Symptoms of IBS & Celiac Disease
Although IBS and celiac disease have many similar symptoms, they also vary in a few different ways.
IBS and celiac can both present with symptoms such as:
- abdominal pain
- bloating
- gas
- constipation and/or diarrhea
However, celiac may also present with specific symptoms or conditions outside the gut, such as:
- weight loss
- iron deficiency
- joint pain
- migraines
- reproductive issues
- osteoporosis
- a skin rash called dermatitis herpetiformis.
It is important to know that in some cases, celiac disease may present with no symptoms and be found incidentally, or only present with symptoms outside the intestine, which is why it’s important to talk to your doctor should you experience any of these.
How Diet Plays a Role
Whether you have celiac or IBS, diet and lifestyle changes can help, and have shown to be more effective when under the guidance of a registered dietitian. Dietitians can personalize a nutrition care plan that best works for you and takes into account your dietary needs and preferences.
The treatment for celiac disease is to remove gluten, a protein found in wheat, barley, rye, and other variants from the diet and requires complete adherence for life – even cross contamination with traces of gluten can trigger symptoms and intestinal damage.
To date, the Low FODMAP diet is one of the most well-researched diets that shows significant symptom improvement for ~50-80% of those with IBS. 3 FODMAPs are types of carbohydrates that are either poorly absorbed in the intestine, or that ferment in the gut, leading to digestive distress. The low FODMAP diet involves significantly reducing intake of these carbohydrates for a short period of time, followed by strategic reintroduction to see which FODMAPs trigger which IBS symptoms.
Interestingly, some individuals with celiac disease may carry an overlapping diagnosis of IBS. Studies show that those with celiac disease with persistent gut symptoms, despite adherence to a gluten free diet, may benefit from the low FODMAP diet. If you struggle with ongoing symptoms, your gastroenterologist and dietitian can help to determine if this is an option for you.
While the diets for celiac disease and IBS are different, they do have some similarities.
Those with celiac must strictly avoid wheat, barley and rye due to its gluten content. On the other hand, those with IBS following a low FODMAP diet must drastically reduce their intake of wheat, barley, rye, and other variants, due to a type of carbohydrate called oligosaccharides. Because of this, some, but not all gluten free foods are low in FODMAPs. In fact, companies that specialize in certified gluten free food products also seek out low FODMAP certification, as they can help both patient populations.
One of these companies is Dr. Schar, who is well known in the gluten free community.
They have a line-up of delicious products that are both low FODMAP and gluten free, helping those with celiac and IBS alike.
Their certified low FODMAP and gluten free products include:
- Pizza Crust
- Baguette
- Ciabatta
- Multigrain Ciabatta
- Deli Style Sourdough
- Deli Style Sourdough Seeded
- Breadsticks
- Entertainment Crackers
- Multigrain Crackers
- Crackers
- Rosemary Crackers

References
- Health Canada. 2018. Celiac disease – the gluten connection. https://www.canada.ca/en/health-canada/services/food-nutrition/food-safety/food-allergies-intolerances/celiac-disease.html
- Lovell RM and Ford AC. Global prevalence of and risk factors for irritable bowel syndrome: A meta-analysis. Clin Gastroenterol Hepatol. 2012 Jul;10(7):712-21.e4.
- Altobelli, E., Del Negro, V., Angeletti, P. M., & Latella, G. (2017). Low-FODMAP Diet Improves Irritable Bowel Syndrome Symptoms: A Meta-Analysis. Nutrients, 9(9), 940. https://doi.org/10.3390/nu9090940