It can be hard to know, as both coeliac disease and gluten (wheat) intolerance present with similar symptoms like, abdominal pain, bloating, diarrhoea, constipation, fatigue, headaches, nausea, vomiting, skin conditions and joint pain. There is increasing evidence of symptoms such as anxiety and feelings of depression too. The severity of symptoms will vary from person to person for both conditions. It’s important to note that a lot of patients with coeliac disease do not have symptoms at all.

Do you need to know?

If the symptoms go away when you stop eating gluten, wouldn’t you just omit gluten from your diet? Do you need an actual diagnosis? The answer is YES.

It is important to have a definitive diagnosis, because both conditions are quite different in terms of the long-term implications.

Let’s start by explaining the difference between the two conditions.

Coeliac Disease

In coeliac disease, the presence of gluten stimulates the immune system to attack the lining of the small intestine. The resulting damage to the intestines is called villous atrophy. As coeliac disease is autoimmune in nature, the gluten doesn’t directly cause the damage, instead it triggers the immune system to cause the damage. This is particularly worrying, as it means the body is unable to properly absorb much-needed nutrients and minerals when food is digested.

Whilst there is no cure for coeliac disease, following a strict gluten-free diet is imperative to help minimise symptoms and keep the condition at bay. This is vital, even if symptoms are very mild, as even the smallest amount can have detrimental effects on the body.

These long- term risks include osteoporosis, other autoimmune conditions such as thyroid disease, type 1 diabetes and rheumatoid arthritis. Coeliac disease may also contribute to the development of anaemia (low blood count), micronutrient deficiencies (e.g. iron, folate, B12, calcium, vitamin D), malnutrition, depression, infertility, and even cancer, if left untreated. The long-term risks resolve on a strict gluten free diet.

Approximately 1 in 70 Australians have coeliac disease. However, only 20% of this number are diagnosed. This means the vast majority of Australians who have coeliac disease don’t yet know it. Knowing the diagnosis will mean that appropriate medical assessments can take place.

Gluten (Wheat) Intolerance

With gluten (wheat) intolerance, the mechanism is poorly understood, but it is thought that there is a direct reaction to wheat, gluten or even the carbohydrates (FODMAPs) in wheat during the process of digestion, causing abdominal symptoms. There is still no actual ‘test’ for gluten (wheat) intolerance, and scientists are yet to determine the root cause of the condition.

Unlike people with coeliac disease, people with a gluten (wheat) intolerance may find they can tolerate a small amount of gluten in their diets, and there are no long term heath problems.

Testing for coeliac disease is a 3 step process

1. The Gluten Challenge

It is important to be on a normal diet (including gluten) for 6 weeks prior to testing. The Gluten Challenge requires adults to eat a minimum of 4 slices of wheat based bread (or equivalent) each day.

2. Screening using a blood test

The coeliac serology (blood test) measures antibody levels in the blood, which are typically elevated in people with untreated coeliac disease, due to the body’s reaction to gluten. Immediate relatives of those diagnosed with coeliac disease should also be screened because you can have this disease and no symptoms.

A diagnosis of coeliac disease should not be made on the blood test alone. A positive blood test always needs to be followed by a small bowel biopsy to provide a definitive diagnosis. Also coeliac serology is negative in 5-10% of patients with coeliac disease.

3. A small bowel biopsy is essential to confirm diagnosis

This involves a gastroscopy, which is a simple day procedure performed whilst under a light anaesthetic sedation. During this procedure, your gastroenterologist will take several tiny samples (biopsies) from the small bowel. These biopsies are examined under a microscope to confirm the presence of villous atrophy (damage to the intestinal lining). If positive for villous atrophy, then the diagnosis for coeliac disease is positive.

If the biopsy is negative for villous atrophy, you do not have coeliac disease even if the serology is positive (false positive serology occurs in 3-5% of people). There may be other reasons for your symptoms, one if which could be Gluten (wheat) Intolerance.

In addition, there’s gene testing ..

Gene testing (HLA genes) may be useful only in select cases where the diagnosis of coeliac disease is unclear. It is performed on a blood test by your doctor. The gene test on its own cannot diagnose coeliac disease. If the gene test is positive, confirmation of coeliac disease still requires serology and a small bowel biopsy.

Gene testing can be helpful if you have symptoms but the coeliac serology is negative. If the gene test is negative it effectively rules out coeliac disease.


It is important to know if you have coeliac disease because it is imperative that you stick to a gluten free diet and are assessed for possible complications of this condition for the long term. If managed effectively, those with coeliac disease manage very well. If you do not have coeliac disease, your doctor may investigate further to rule out other conditions, but may confirm that it is in fact gluten (wheat) intolerance. However, before cutting anything out, it’s important you check in with their GP first to make sure it’s gluten causing the reaction and not another condition entirely, such as irritable bowel syndrome.

Coeliac Australia offer a free self-assessment quiz online so you can check if your symptoms could be coeliac disease. Take the 3 minute quiz here to see if you might be at risk. 

If you have been referred for a gastroscopy to confirm coeliac disease and would like to book an appointment, please call us on 9468 9700 or email [email protected]

Disclaimer – This article is for general information and educational purposes only. It is not a substitute for professional advice. Always consult a registered health professional regarding any health-related diagnosis or treatment options.