How Do You Know If You Have Coeliac Disease? Symptoms, Testing & What To Avoid

Many people experience bloating, fatigue or stomach discomfort from time to time. It’s easy to blame stress, a heavy meal or “just being sensitive to gluten.” But for some, these symptoms may point to something more serious — coeliac disease.

Coeliac disease is not the same as a mild food intolerance. It is an autoimmune condition where the body reacts to gluten — a protein found in wheat, barley and rye — by attacking the lining of the small intestine. Over time, this can interfere with nutrient absorption and lead to long-term health complications if left untreated.

The challenge is that symptoms can vary widely. Some people experience clear digestive issues, while others may have subtle signs like iron deficiency, fatigue or skin problems. In some cases, there are very few obvious symptoms at all.

So how do you know if you should be tested?

In this guide, we’ll explore the common signs of coeliac disease, how it’s diagnosed, what sets it apart from gluten sensitivity, and what you need to avoid if you are diagnosed.

What is coeliac disease?

Coeliac disease is a lifelong autoimmune condition triggered by gluten — a protein found in wheat, barley and rye.

When someone with coeliac disease eats gluten, their immune system mistakenly attacks the lining of the small intestine. This reaction damages tiny finger-like projections called villi, which are responsible for absorbing nutrients from food.

Over time, this damage can reduce the body’s ability to properly absorb essential nutrients such as iron, calcium, folate and vitamin B12.

How common is coeliac disease in Australia?

Coeliac disease is more common than many people realise — and it often goes undiagnosed.

In Australia, it’s estimated that over 1 in 70 people are affected. However, because symptoms can vary widely and may be mild or mistaken for other conditions, the condition is frequently overlooked. In fact, around 4 out of 5 Australians with coeliac disease remain undiagnosed.

This means many people may be living with ongoing intestinal damage without realising it.

Coeliac disease is also genetic, meaning it can be passed down from parent to child. If a close family member has been diagnosed, your risk is higher.

Certain groups are also more likely to develop coeliac disease, including people:

• With a family history of coeliac disease
  
• With type 1 diabetes
  
• With Down syndrome
  
• With other autoimmune conditions (such as thyroid disease)
  
• Experiencing unexplained infertility
  
• With ongoing IBS-type symptoms, particularly diarrhoea

What happens inside the small intestine?

The small intestine plays a key role in digestion and nutrient absorption. The villi increase the surface area of the intestine, allowing nutrients to pass efficiently into the bloodstream.

In coeliac disease:

• The villi become inflamed and flattened
  
• Nutrient absorption is impaired
  
• Deficiencies can develop, even if a person is eating a balanced diet

This is why coeliac disease can affect many parts of the body — not just the digestive system.

Is coeliac disease the same as gluten intolerance?

Coeliac disease is different from:

• A wheat allergy (which involves a different immune response)
  
• Non-coeliac gluten sensitivity (which does not cause intestinal damage)

Because coeliac disease is autoimmune, even small amounts of gluten can trigger inflammation and intestinal injury.

Can coeliac disease be cured?

Currently, there is no cure for coeliac disease.

The only effective treatment is a strict, lifelong gluten-free diet. When gluten is completely removed, the small intestine can begin to heal, and symptoms often improve over time.

Common symptoms of coeliac disease

One of the reasons coeliac disease is often missed is that symptoms can vary greatly from person to person. Some people experience obvious digestive problems, while others have subtle or non-digestive signs.

In some cases, there may be very few noticeable symptoms at all — even though intestinal damage is occurring.

Because coeliac disease affects the small intestine, digestive symptoms are common. These may include:

• Ongoing bloating
  
• Diarrhoea
  
• Constipation
  
• Abdominal pain or cramping
  
• Nausea
  
• Excessive gas

Some people may also experience unexplained weight loss or difficulty maintaining weight. However, not everyone with coeliac disease has severe digestive issues. This is why relying on stomach symptoms alone can be misleading.

Common non-digestive symptoms in coeliac disease include:

• Persistent fatigue
  
• Iron deficiency or unexplained anaemia
  
• Frequent headaches
  
• Brain fog or difficulty concentrating
  
• Joint or muscle pain
  
• Mouth ulcers
  
• Mood changes

Some people also develop a specific skin condition called dermatitis herpetiformis — an itchy, blistering rash linked to gluten sensitivity.

How does coeliac disease present in children?

In children, symptoms may look different. Instead of classic digestive complaints, signs can include:

• Delayed growth or puberty
  
• Poor weight gain
• Irritability
  
• Ongoing tummy pain
  
• Delayed development

Can you have coeliac disease without symptoms?

This is sometimes called “silent” coeliac disease.

Even without obvious symptoms, gluten exposure can still damage the intestinal lining and increase the risk of long-term complications. This is why people with a family history or other risk factors may be tested even if they feel relatively well.

If symptoms are persistent, unexplained, or affecting quality of life, it’s worth discussing testing with your healthcare provider.

How is coeliac disease diagnosed?

If you think you may have coeliac disease, getting properly tested is an important first step. It can be tempting to remove gluten straight away to see if you feel better, but doing this too early can actually interfere with accurate diagnosis.

Why you should not start a gluten-free diet too soon

It’s important not to begin a gluten-free diet until testing is complete.

Starting early can:

• Reduce antibody levels
  
• Allow the intestine to begin healing
  
• Make biopsy results unclear
  
• Complicate long-term diagnosis

Diagnosis involves a clear medical process, and each step plays an important role.

1. Initial blood testing

In most cases, your GP will begin with a blood test. This test looks for specific antibodies that the body produces when someone with coeliac disease consumes gluten. The most commonly measured marker is called tissue transglutaminase antibodies (tTG-IgA).

If these antibody levels are elevated, it suggests that the immune system is reacting to gluten.

It’s very important to continue eating gluten before and during testing. If gluten is removed too soon, antibody levels can drop, which may lead to a false-negative result. 

2. Referral to a specialist

If the blood test suggests coeliac disease, your GP will usually refer you to a gastroenterologist for further assessment, because a blood test alone is not considered enough to confirm coeliac disease.

3. Endoscopy and small bowel biopsy

To confirm coeliac disease, a specialist will typically recommend an endoscopy with a small bowel biopsy.

During this procedure, a thin, flexible tube with a camera is passed through the mouth into the small intestine. Small tissue samples are taken from the lining of the intestine and examined under a microscope.

If the tiny finger-like projections (villi) are flattened or damaged, this confirms coeliac disease.

What happens after diagnosis?

If coeliac disease is confirmed, treatment focuses on strict, lifelong gluten avoidance. Over time, the small intestine can begin to heal, and many symptoms improve significantly.

Your healthcare provider may also monitor nutrient levels, particularly iron, calcium, vitamin D and B vitamins, to ensure deficiencies are corrected.

If you suspect coeliac disease, the best next step is speaking with your GP before making any dietary changes.

What to avoid if you have coeliac disease

Foods that contain gluten

Gluten is found in three main grains:

• Wheat
  
• Barley
  
• Rye

This means you’ll need to avoid common foods such as:

• Regular bread, wraps and rolls
  
• Pasta and noodles made from wheat
  
• Most breakfast cereals
  
• Cakes, biscuits and pastries
  
• Traditional pizza bases
  
• Couscous and semolina

It’s also important to remember that wheat has many different names, including spelt, durum, kamut and farro — all of which contain gluten.

Hidden sources of gluten

Gluten isn’t always obvious in every food you see. It’s often used as a thickener, stabiliser or flavour enhancer in processed foods.

Common hidden sources include:

• Soy sauce (unless labelled gluten-free)
  
• Gravies and sauces
  
• Salad dressings
  
• Processed meats and sausages
  
• Stock cubes
  
• Some confectionery
  
• Certain medications and supplements

Reading ingredient labels carefully becomes part of daily life with coeliac disease. In Australia, allergens including gluten-containing cereals must be declared, but doing the due diligence on your part by checking every product is still important.

The risk of cross-contamination

For people with coeliac disease, even tiny amounts of gluten can cause harm. Cross-contamination happens when gluten-free food comes into contact with gluten-containing products.

Common examples include:

• Using the same toaster for regular and gluten-free bread
  
• Shared chopping boards or utensils
  
• Frying gluten-free foods in oil that has been used for battered foods
  
• Bulk food bins in supermarkets

At home, it may mean keeping separate kitchen tools or clearly labelling gluten-free items. When eating out, it’s also important to ask how food is prepared.

Oats: Are they safe if you have coeliac disease?

Pure, uncontaminated oats do not naturally contain gluten. However, they are often processed in facilities that also handle wheat, leading to higher chances of cross-contamination.

In Australia, only oats that are specifically labelled gluten-free should be considered — and even then, some individuals with coeliac disease may still react. Therefore, it is always good to seek medical advice before introducing oats into your diet.

Why strict avoidance matters

Unlike a food intolerance, coeliac disease involves an autoimmune response. Even if symptoms are mild or absent, intestinal damage can still occur with gluten exposure.

Long-term, repeated exposure may increase the risk of:

• Nutrient deficiencies
  
• Osteoporosis
  
• Fertility issues
  
• Other autoimmune conditions

What can you eat instead?

Being diagnosed with coeliac disease can feel overwhelming at first — especially when you’re focused on everything you need to avoid. But the good news is that there are still plenty of nutritious, satisfying foods you can safely enjoy.

Naturally gluten-free whole foods

Many everyday foods are naturally gluten-free and form the foundation of a balanced diet. These include:

• Fresh fruit and vegetables
  
• Lean meats and poultry
  
• Fish and seafood
  
• Eggs
  
• Legumes and beans
  
• Nuts and seeds
  
• Milk, yoghurt and most natural cheeses

These whole foods are not only safe for coeliac disease, but also rich in fibre, protein, vitamins and minerals.

Gluten-free grains and carbohydrate options

While wheat, barley and rye are off the menu, there are several gluten-free grains and starches you can include:

• Rice
  
• Quinoa
  
• Buckwheat
  
• Corn
  
• Millet
  
• Sorghum
  
• Polenta
  
• Potatoes and sweet potatoes

There are also many gluten-free alternatives available, such as:

• Certified gluten-free bread
  
• Gluten-free pasta
  
• Gluten-free cereals
  
• Gluten-free baking mixes

Look for products labelled “gluten-free,” as this indicates they meet strict safety standards.

Clean, gluten-free fuel with Chief Nutrition

If you’re following a strict gluten-free diet, finding convenient, high-protein snacks can sometimes feel limiting. That’s where Chief Nutrition offers a practical option.

Chief Nutrition’s range includes:

• Grass-fed beef bars and biltong
  
• Protein bars
  
• Collagen protein powders
  
• Whey protein powder
  
• Beef liver supplements

Many of these products are naturally gluten-free, making them suitable for those avoiding wheat, barley and rye. They provide a convenient source of protein and nutrients — helpful when you’re adjusting to new dietary restrictions or looking for on-the-go options.

Whether you need a savoury snack, a post-workout protein boost, or a wholefood-based supplement, Chief Nutrition products can fit into a balanced gluten-free lifestyle.

👉 Shop Chief Nutrition healthy snacks and supplements at Aussie Pharma Direct.

As always, check product labels to ensure suitability for your individual needs.

Conclusion: When in doubt, get tested

Coeliac disease can present in many different ways — from obvious digestive discomfort to subtle symptoms like fatigue or iron deficiency. Some people experience significant symptoms, while others may have little to no warning signs at all.

That’s why awareness matters.

If you have ongoing digestive issues, unexplained nutrient deficiencies, a family history of coeliac disease, or symptoms that don’t seem to resolve, it’s worth speaking to your GP about testing. Early diagnosis can prevent long-term complications and allow the small intestine to heal properly.

With accurate diagnosis and a strict gluten-free diet, people with coeliac disease can live full, healthy lives. It may take some adjustment at first, but with the right information and planning, managing coeliac disease becomes both practical and sustainable.