Prof Sanders is Professor of Gastroenterology at Royal Hallamshire Hospital and University of Sheffield. His specialist interest is Coeliac disease and gluten, inevitably.
Reading this book perhaps is a must if you want concrete and reliable evidence based information written in a way that is easily understood. It gives a great overview of gluten and food intolerance, food sensitivities, Irritable Bowel Syndrome, Irritable Bowel and Coeliac disease. So, there is something for everyone – those who are diagnosed clinically and those who think they need to go gluten-free for the benefits of general and digestive health.
Question-Answer format is probably the best way to review the information in the book. So this is how the rest of the post is going to go.
Q: I have symptoms (stomach pain, bloating, diarrhoea, indigestion, constipation...) of gluten sensitivity. What should I do?
A: Go and see you doctor.
The only way to confirm if the symptoms you are experiencing are a sign of Coeliac disease is to have medical tests done. It is pointed out that you must not restrict gluten before the tests because the results of the tests wouldn’t be accurate in this case.
For anyone to develop Coeliac disease, there must be a certain expression of genes. In other words, your genetic make up makes you prone to developing gluten sensitivity. However, having the “right” genes tells only half of the story. Even if you have specific genes, you might not develop the condition and medical community is not sure why that happens.
Coeliac disease is an autoimmune disorder meaning the cells in the small intestine attack themselves, provided there is a trigger which is in this case is gluten. In any autoimmune condition, our body produces antibodies, particles which are released in the blood stream to fight unfamiliar foreign bodies such like bacteria in immune conditions or gluten in Coeliac disease. Therefore, a doctor would ask you for a blood test and if that is positive you’d be referred for a biopsy of your small intestine.
If both tests confirm you have Coeliac Disease, then you are saved - gluten-free diet is your cure.
Given IBS is diagnosed by excluding other gut conditions, you might have to endure this first to make sure your gut symptoms are not a product of Coeliac disease of Inflammatory Bowel Disease.
Q: What is the difference between food allergy and intolerance?
A: In short, clues of food allergy lies in antibody tests. However, even if the test is positive, it doesn’t mean you have an allergic reaction to that food. Intolerance, on the other hand, is a freely used term and there are no diagnostic tests to confirm food intolerance.
Food allergy is an immunological response to a particular substance and can be diagnosed by the presence of particular antibody. Allergy testing is commonly done by skin prick tests. However, you can be sensitive to a food allergen and don’t have the allergy. Therefore, only an expert can diagnose food allergy based on your medical history and your test results.
Food intolerance doesn’t appear as an immunological response to food and there is no diagnostic test for it. Symptoms for food intolerance overlap with food allergy. Intolerance is usually diagnosed by exclusion and previous medical history. There is not "good science" in conventional Western medicine to explain food intolerance which only leads to potentially charlatan claims and tests endorsed by the media.
However, as Prof Sanders points out, “the absence of evidence should not be used as proof of no effect”. Any gluten sensitivity related symptoms you are experiencing are valid, it is just our current medical paradigm is not able to provide in depth understanding of food intolerance.
Q: What about the link with IBS and gluten? Or is it the wheat?
A: It exists but it’s not cause and effect. At least, there is little evidence to claim causality.
In short, people with IBS who eat gluten products, experience an immunological reaction when gluten crosses the lining of the small intestine which results in gastrointestinal symptoms.
In one German study, people with IBS who produce gliadin (component of gluten molecule) antibodies and have the genes found in Coeliac disease responded well to gluten-free diet (1). this effect, however, was observed and little conclusion can be made about causality between gluten free diet and improved IBS symptoms.
What is needed to confirm these observations is a randomised controlled trial. Monash University in Australia, the leading research centre in FODMAP foods and IBS symptoms, conducted a double blind trial were people with IBS were given gluten free or 16g of gluten-rich (5 slices of bread would approximately contain 16g) bread or muffins (2). Double blind control trial means that neither participants nor researchers knew gluten-free or gluten based flour products were consumed by participants. It only took a week of the trial to see that participants eating gluten-rich bread/muffins reported worse gut symptoms than participants in the gluten-free arm of the trial. The researchers concluded that people who were on gluten-free bread and muffin consumption had 28% improvement in their IBS symptoms compared to participants in the gluten arm. So, people who did eat gluten-free bread and muffins were feeling better but gluten was not the cure to symptom-free IBS. It just highlights the fact that there are so many different factors affecting gut symptoms.
Q: Should I go gluten-free or low FODMAP?
A: Gluten free diet is easier to follow than low FODMAP and does improve symptoms. However, it’s your choice.
It depends on a few things such as your motivation to feel better, your current awareness of the foods you are eating that may be causing symptoms, the support of the medical and nutrition professionals as well as your family and friends. Experimenting with a way of eating to improve symptoms can be a lonely journey and you have to have people on board with you. Professional advice is great to keep you on the track without causing more damage to your health and moral support from family to help you adhere to the diet. So, it's not only "eat this not that and feel better" but, also, having the right mindset to stick to the diet which is important.
After all, is going gluten-free necessary for a good health of digestive system?
It is not necessary. It is not required. It is not a be-all-end-all answer. However, it is likely to improve IBS symptoms. "It is the dosage that makes the poison," as it was once famously said by Paracelsus. We all have different threshold levels: your gut may react to a slice of bread or only show a signal of discontent after 3 slices. Self-monitoring and awareness over diving head down to all gluten-free trap is key.
1. Wahnschaffe, U., Schulzke, J.D., Zeitz, M., Ullrich, R. (2007) Predictors of clinical response to gluten-free diet in patients diagnosed with diarrhea-predominant irritable bowel syndrome. Clinical Gastroenterology and Hepatology. 5(7), pp. 844-50.
2. Biesiekierski,J.R., Newnham, E.D., Irving, P.M., Barrett, J.S., Haines, M., Doecke, J.D., Shepherd, S.J., Muir, J.G., Gibson, P.R. (2011) Gluten causes gastrointestinal symptoms in subjects without celiac disease: a double-blind randomized placebo-controlled trial. American Journal of Gastroenterology. 106(3), pp.508-14.