What is Gluten Intolerance?

What is Gluten Intolerance?

Understanding the causes, symptoms, diagnosis, and management of gluten intolerance

Gluten intolerance is one of the most common forms of food intolerance globally. In this guide we aim to provide detailed information about gluten intolerance, also known as non-celiac gluten sensitivity. We will cover the causes, symptoms, diagnosis, management, and common questions related to gluten intolerance.

What is gluten intolerance?

Gluten is a protein that is typically found in several popular foods and ingredients such as wheat, bread, pasta, cereal, beer and even food additives.

Gluten intolerance is a condition which causes an adverse reaction in the body whenever gluten is consumed through a certain food. Unlike Coeliac disease, it does not trigger an autoimmune response or cause any damage to the small intestine.

Gluten intolerance can present a number of symptoms that may cause discomfort in individuals when gluten is consumed.

Gluten intolerance is one of the most common types of food intolerance, however it is often one of the most misdiagnosed food intolerances due to many people choosing to self diagnose. Research has shown that people who believe they had a gluten intolerance were more likely to be sensitive to FODMAP's. It is important to get a larger picture of your reactions to food with a comprehensive food intolerance test, instead of trying to pinpoint this to one particular ingredient.

Research suggests that genetics, and environmental factors can contribute to developing a gluten intolerance, however the exact causes and mechanisms of a gluten intolerance is not fully understood.

Causes of gluten intolerance:

While the exact causes of gluten intolerance cannot be pinpointed to one specific root cause, there are a number of studies that have pinpointed some contributing factors in developing gluten intolerance. Genetics, gastrointestinal disorders, gut bacteria deficiencies, diet and lifestyle factors can all contribute to developing gluten intolerance.


Typically, gluten symptoms will include digestive symptoms and non-digestive symptoms which include:

Digestive symptoms:

  • Abdominal/stomach pain
  • Bloating
  • Gas
  • Diarrhoea
  • Constipation
  • Nausea and vomiting

Non-digestive symptoms:

  • Fatigue/tiredness
  • Headaches/migraines
  • Brain fog
  • Aches and pains (particularly in joints)
  • Skin rashes
  • Mood changes including anxiety and depression

The symptoms you may experience will be dependent on the severity of your intolerance, it is possible that individuals can experience more than one symptom.

When should I be concerned?

Gluten intolerance is not considered to be life threatening or cause any severe complications. However, it is important to look out for additional symptoms that may not be a sign of gluten intolerance and could indicate an underlying condition.

Symptoms that require medical attention:
  • Unexpected/unintentional weight loss
  • If your symptoms are causing severe or persistent discomfort
  • Symptoms of anaemia
  • Dehydration, which can be caused by nausea

For a more comprehensive list of side effects of a food intolerance and how to cope with them, we recommend reading our helpful guide on food intolerance symptoms.

What foods contain gluten?

Gluten is most commonly found in:

Wheat-based products:

Bread, pasta, cereal, baked goods, and flour

Barley-based products:

Malt, beer, and certain food additives

Rye-based products:

Rye bread, rye beer, and some cereals.

Please note that this is not an exhaustive list, for a full list of foods that contain gluten we recommend visiting the Coeliac Disease Foundation.

When it comes to identifying gluten containing foods, particularly on food packaging, it is important to note that it will not specifically be listed as “gluten”, but instead will be shown as the gluten containing ingredient, most likely wheat, barley or rye.

All packaged foods in the UK, must conform to strict product labelling, meaning that only foods that are gluten free, can apply gluten free wording to its packaging. If the product does not specify that it is gluten free, it is highly likely that it will contain gluten. Other things to look out for is the gluten free logo, which can be seen below.

Gluten free logo that appears on food packaging in the UK

Is gluten intolerance the same as coeliac disease?

No, gluten intolerance (non-coeliac gluten sensitivity) is different to coeliac disease. Coeliac disease triggers an autoimmune response which causes the immune system to start attacking healthy tissue when gluten is consumed, as a result; coeliac disease can damage the small intestine.

Gluten intolerance does not trigger an autoimmune response or cause any damage to the intestines; however it can cause discomfort due to some of the symptoms it presents.

Living with gluten intolerance

Living with gluten intolerance will largely involve adopting a gluten-free lifestyle, there are a number of strategies that can help to improve your quality of life reduce your symptoms.

Follow a gluten-free diet

Try to eliminate gluten completely from your diet, gluten intolerance related symptoms will typically arise when gluten has been consumed. People tend to find lifelong relief from symptoms when gluten has been completely removed from their diet. If you are considering a gluten free diet, you can chat to a member of our nutrition team, or do some further research on whether a gluten free diet is right for you.

Create a personalised balanced diet

Removing gluten from your diet can also mean that you are removing foods that provide you with valuable nutrients. It is important to eat a balanced diet that is low in fats and high in fibre to ensure that you still have an intake of valuable nutrients.

Avoid cross contamination between gluten containing and gluten free foods

Even tiny amounts of gluten can trigger your symptoms. It is important to store, prepare and cook gluten containing and gluten free foods separate from each other.

Finding gluten-free alternatives

Gluten free foods are more popular than ever, with a whole range of gluten free brands providing healthy foods that don’t contain gluten but still provide you with all the other nutritional goodness and taste.

How is Gluten Intolerance Diagnosed?

A gluten intolerance can be quite broad to try and identify, as gluten is present in ingredients such as wheat, barley, and rye. The Feel Gut food intolerance blood test measures IgG antibody levels in your blood against over 200 types of food with wheat, barley and rye all being included in the test.

Our gut microbiome health test kit can also identify whether the bacteria in your gut increases your risk of gluten intolerance. 

Other conventional methods of testing for a food intolerance test include keeping a food diary to monitor which foods trigger your symptoms.

Can gluten intolerance be prevented?

There is no research to suggest that there is a recommended way to prevent a gluten intolerance. However, maintaining a healthy balanced diet can help to avoid known factors that can contribute to gluten intolerance such as gut bacteria deficiencies and gastrointestinal disorders.

Can gluten intolerance go away by itself?

Gluten intolerance is typically a lifelong condition, it is unlikely that you will be able to reverse the signs of a gluten intolerance, however by removing gluten containing foods from your diet, it is possible to significantly reduce and even stop your symptoms. 

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