Gluten intolerance? Coeliac? What’s the difference?

A high percentage of people are unable to digest gluten properly which causes a vast array of problems in the gut. When food that contains gluten reaches your intestines, enzymes produced in gliadin and glutenin.


As the peptides (gliadin and glutenin) make their way through your digestive system, your immune system in your gut, the gut-associated lymphoid tissue (GALT) reviews them for potentially harmful substances.

When one doesn’t have an issue with gluten, the proteins are efficiently absorbed. However, in those that do have a sensitivity or intolerance, the GALT identifies gluten peptides as potentially harmful substances, and therefore antibodies are produced by the body to attack it.

Trouble digesting gluten

When your body produces antibodies to defend itself against gluten peptides, the intestinal barrier may also become compromised, decreasing your ability to absorb nutrients and making the walls of your intestine ‘leaky’, allowing more substances through. This can manifest itself in digestive symptoms, including bloating, constipation, diarrhoea and weight.

Gluten also causes the gut cells to release a protein called zonulin. Zonulin's role is to open up the spaces between the cells of the intestinal lining and this is a process that is essential for the efficient absorption of nutrients. However, in those with gluten sensitivity, the gut cells remain open allowing much larger protein molecules (that are potentially harmful) to be absorbed into the bloodstream.

When these tight junctions remain open, you have a leaky gut. When your gut is leaky, harmful things like bacteria, toxins, heavy metals and undigested food particles can leak through your intestines into your bloodstream. Once they get into your bloodstream, they are transported to the liver. This puts a strain on your liver function and most people who have had a leaky gut for some time eventually go on to develop poor liver health.

Although some people don’t feel poorly or uncomfortable when eating it, that doesn’t mean it isn’t causing them problems. Sometimes an immune response has been going on for some time before actual symptoms are noted.

CourgettiWhat is coeliac disease?

At one end of the scale is coeliac disease - an allergy to gluten that can cause severe diarrhoea, extreme tiredness and poor absorption of nutrients. However, not all people have all of these symptoms. Coeliac is usually diagnosed via a blood test looking for antibodies against gluten proteins, but some blood tests come back clear despite there being gut damage which is seen if investigated with an endoscopy.

Those with coeliac disease have to be very careful to avoid even small amounts of gluten, as this can trigger a fairly quick allergic response.

What is gluten intolerance?

Gluten intolerance can be a spectrum of difficulty in digesting gluten. This can present itself as bloating, constipation or loose stools, stomach pain, colon pain, brain fog, joint pain, headaches and low energy. The problem with gluten intolerance is that unlike allergies which are quick to show, intolerances can have a delayed reaction from a few hours to three days.

Whilst there are tests that measure if you are producing antibodies to gluten even if you aren’t coeliac, the best way is to remove gluten for 10 days and then reintroduce it looking, for new reactions. If you have improved stools, clearer thinking, less bloating and more energy you may choose to go gluten-free.

Unlike coeliacs, this doesn’t mean you have to scan every label for each trace of gluten, but avoid all obvious sources by switching to gluten-free bread (I like Genius), gluten-free pasta and checking soups and sauces. This doesn't mean that it is healthy to buy lots of products from the 'Free From' section of supermarkets, as many items such as gluten-free cakes have a lot of sugar and preservatives. It is easy to go naturally gluten-free by swapping some gluten-free products for root vegetables, rice, sweet potatoes and fresh fruit.

If you have digestive disorders or problems with energy, you may well want to try going without gluten for 10 days and see if they improve, although, with digestive problems, further gut support is often needed.

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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Wantage, Oxfordshire, OX12 8NG
Written by Samantha Silvester, C.H.Ed (Dip.Nut.Th)
Wantage, Oxfordshire, OX12 8NG

Sam is Registered Nutritionist who has been practicing for 10 years from her home in Lambourn near the beautiful Downs. She specialises in digestive disorders, auto immune conditions and weight loss - promoting 'healthy eating for ever' rather than diets.

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