Coeliac disease: understanding four common myths

Coeliac disease is an autoimmune condition in which gluten sets off an attack on the small bowel. Damage to its lining can reduce nutrient absorption. Gluten is a protein found in wheat, barley and rye. Having symptoms after eating those foods does not, by itself, establish the diagnosis.

Four common misunderstandings concern the age at diagnosis, symptoms outside the gut, the difference from gluten sensitivity, and what happens when a gluten-free diet does not settle symptoms. Understanding those differences helps people seek the right tests and follow-up rather than diagnose themselves.

Myth 1: It is usually discovered in childhood

The condition can begin at any age after gluten first enters the diet. Diagnosis often comes much later. US figures cited in the source put the average age at diagnosis between 46 and 56, with about a quarter diagnosed after 60. These are not Australian population estimates and do not rule the disease in or out at another age.

It is somewhat more common in women and in people with other autoimmune conditions, including type 1 diabetes and Hashimoto thyroiditis, which can cause an underactive thyroid. Dermatitis herpetiformis, an intensely itchy blistering skin condition, is also associated with coeliac disease.

Why a susceptible person develops active disease is not fully understood. Infection, surgery or major emotional stress have been proposed as possible triggers, not established explanations for every case. Some adults are investigated only after anaemia or osteoporosis reveals the consequences of poor nutrient absorption.

Myth 2: It affects only digestion

The small bowel normally has tiny finger-like projections called villi that absorb nutrients. In coeliac disease, the immune reaction inflames and flattens them. Abdominal pain, bloating and diarrhoea can occur, but their absence does not mean the bowel is unharmed.

Symptoms may involve the nervous system, hormones, muscles or bones. Difficulty thinking clearly, changes in menstrual periods, and muscle or joint pain are examples. The pattern varies, so persistent unexplained symptoms or deficiencies deserve medical assessment rather than assuming that everyone must have obvious bowel trouble.

Myth 3: Feeling unwell after gluten proves coeliac disease

Coeliac disease and non-coeliac gluten sensitivity are different. Coeliac antibody blood tests are screening tests; a gastroenterologist usually confirms the diagnosis with samples from the small bowel taken during gastroscopy. In some children, a specialist can diagnose without a biopsy if specific criteria are met.

Non-coeliac gluten sensitivity does not have the same characteristic antibodies and bowel injury. People may nevertheless report digestive discomfort, brain fog, poor concentration, aches or fatigue after gluten-containing foods. It is not well defined, and gluten may not be the responsible ingredient in every case.

One alternative is FODMAPs: fermentable carbohydrates present in wheat and many other foods. Their full name covers oligosaccharides, disaccharides, monosaccharides and polyols. Gut bacteria can ferment these carbohydrates, producing gas and bloating. Restrictive diets are best discussed with a qualified dietitian.

Wheat allergy is another distinct possibility. It can cause itching, swelling or irritation in the mouth and throat, rash, a blocked nose, headache, cramps, nausea or vomiting. A severe reaction can be anaphylaxis. In Australia, for suspected anaphylaxis use the prescribed adrenaline injector immediately if available, then call 000 for an ambulance and follow the allergy action plan.

Myth 4: A gluten-free diet always makes every symptom disappear

A strict lifelong gluten-free diet remains the treatment for confirmed coeliac disease, but some people continue to have symptoms. The source estimates this at around 20% despite efforts to follow the diet. Ongoing symptoms are sometimes described as nonresponsive coeliac disease; they need review and should not be taken as permission to resume gluten.

Accidental exposure can cause intermittent symptoms. Prepared meals or restaurant food may contain gluten despite claims, and contact with gluten-containing foods or equipment can transfer it. A clinician and dietitian can review the diagnosis, diet, contamination risks and other reasons for persistent symptoms.

Research is exploring three approaches: enzymes to digest gluten, blocking tissue transglutaminase to reduce gluten’s ability to provoke an immune reaction, and retraining the immune response not to react to gluten. These were research directions in the source, not established substitutes for the gluten-free diet or a reason to try over-the-counter digestive enzymes as protection.

Get tested before changing your diet

If you suspect coeliac disease, see your GP before removing gluten, because avoidance can make tests less reliable. If you already avoid it, ask how to investigate safely rather than starting a gluten challenge yourself, especially if allergy is possible. A positive gene test shows susceptibility, not a diagnosis. After confirmation, a dietitian can help plan a balanced gluten-free diet and follow-up care.