Find out more about what to look out for & what can help when it comes to managing your diet in our go-to guide 

The variety of ‘free-from’ foods to choose from has come on in leaps and bounds over the past couple of years to provide a greater choice for those who may have been advised by a medical professional to reduce or cut back their gluten intake. 

But what exactly is gluten? Well, it’s a dietary protein found in three types of cereal: wheat, barley and rye, which provides elasticity and gives foods a chewy texture. It can be found in any food that contains those cereals, such as pasta, cakes, breakfast cereals, most breads, certain sauces and some ready meals. 

For some, these foods can lead to an adverse reaction, such as gastric woes or digestive difficulties, shortly after eating them. Some potential reasons behind the reaction include coeliac disease (an autoimmune disease that causes your immune system to attack your digestive tract after you consume gluten), a wheat food allergy (a reaction to proteins found in wheat), gluten intolerance and non-coeliac gluten sensitivity, when symptoms are similar to coeliac disease, but it’s unclear how the immune system is involved and where damage to the gut lining doesn’t seem to occur. 

Here, we’re going to focus on some common food intolerance and non-coeliac gluten sensitivity symptoms (where similar symptoms may be experienced) that are worth exploring, under the guidance of your GP.

Gluten intolerance symptoms explained

According to the NHS, a food intolerance involves having ‘difficulty digesting certain foods and having an unpleasant physical reaction to them’.

A food intolerance may manifest in an array of ways such as tummy pain, bloating, wind and/or diarrhoea that happen usually a few hours after eating the specific food. It may also cause symptoms such as a skin rash, which might come as a surprise to some.

Could gluten be to blame? According to the NHS, it can be tricky to know whether the symptoms you experience are signs of an intolerance to gluten, caused by something else in wheat, or caused by something different altogether. If you think you might be gluten intolerant, it is helpful to monitor your symptoms by recording what you eat and what symptoms you experience in a food diary in the first instance to see if there’s a pattern. It can also be a useful record to show your GP to help them identify the cause of the symptoms, whether that may be coeliac disease, or another dietary-related cause, such as gluten intolerance, non-coeliac gluten sensitivity, a food allergy or a reaction to other foods or ingredients.

Wondering what to look out for? To shed some light on some of the most common symptoms of gluten or food intolerance and non-coeliac gluten sensitivity, how to manage them and how you can reach out for help, we asked registered nutritionist and head of nutrition at Healthspan, Rob Hobson, for his expert insights. 


This happens when your stomach feels swollen or full of gas – particularly after eating. Bloating is a common complaint and the NHS lists it as a symptom for those who could have a food intolerance. 


Need to run to the loo a few hours after eating something containing gluten? Rob highlights that this is a common digestive symptom that can occur if you have a food intolerance.


This can be another common symptom. "One theory is that gluten intolerance can cause a reduced absorption of key nutrients, including iron and B12, low levels of which are associated with fatigue," says Rob.

"Another reason could be simply a case of the amount and type of carbohydrates eaten, which can affect anyone. If you eat high amounts of quickly digested carbohydrates, it can cause rapid fluctuations in blood sugar, potentially leading to fatigue as it drops."

Skin reaction

People with a food or gluten intolerance do not always experience digestive symptoms.

"While seemingly unrelated to digestion, gluten intolerance has been shown to impact on skin," says Rob. A rash, or something like it, might also be a symptom of a different food intolerance.

Low iron levels

An iron deficiency is one of the most common and gluten intolerance "can impact on the absorption of nutrients including iron", explains Rob. "Low levels of iron can lead to symptoms including fatigue, shortness of breath, dizziness, headaches, and pale skin."

Diagnosing gluten sensitivity or intolerance with a healthcare provider

Coeliac disease should be ruled out first. To do this, a simple blood test can be performed at your GP surgery if it offers this service, or at your local hospital, which you can attend via a GP referral. If it’s confirmed you don’t have coeliac disease (if you did, you would have to eliminate all gluten from your diet), but are still concerned about your symptoms, including unexplained weight loss, and suspect it may be a gluten intolerance or a non-coeliac gluten sensitivity, it is still worth booking in with your GP for further investigations. They may suggest you remove gluten from your diet for a period of time to see if your symptoms improve (there currently isn’t a specific test for gluten intolerance). Eating a restricted diet may make it trickier to get the nutrients you need and so your GP should be able to help you find a registered dietitian to support you.

"If gluten seems to be an issue, a dietitian will work through an elimination diet to see if symptoms improve and whether you are able to tolerate a certain amount of a specific food," says Rob.

Managing gluten intolerance

While not everyone with a gluten intolerance will necessarily have to remove gluten from their diet completely, for those who do, following a gluten-free diet isn’t as daunting as it might initially seem. Awareness is increasing in the mainstream food industry and more gluten-free products (including gluten-free breads) are now readily available in supermarkets.

It could be worth cutting out the obvious foods that contain gluten, such as bread, pasta, flour and cereal one at a time for two to six weeks, although only if your food diary revealed you might have an intolerance to one of these, while plain meat (including meat fed on gluten-containing grains), poultry, fish, eggs, cheese, milk, yoghurt, fruits and vegetables, pulses, rice, nuts and seeds, corn and potatoes are all naturally gluten free, according to Coeliac UK.

"Many dishes that traditionally contain gluten can also be adapted to become gluten-free," says Rob. "You could serve your bolognese sauce with gluten-free pasta or rice."

"Eating out shouldn’t be an issue as long as the kitchen staff are clear on what products they have used and whether they contain gluten or not."

"If you aren’t comfortable with this then stick to foods that are clearly gluten-free, which could include grilled fish with vegetables."

And always let the restaurant know of any allergies or intolerances, so they can advise you accordingly.

It’s useful to note that many symptoms of gluten intolerance and non-coeliac gluten sensitivity are similar to coeliac disease, so it’s important not to self-diagnose if you experience any of the above symptoms and book an appointment with your GP so that coeliac disease can be ruled out as a first port of call. 


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