How to sort the ‘wheat from the chaff’ with wheat and gluten sensitivity tests

Do you feel unwell, wiped out or bloated after eating foods containing wheat or gluten such as bread, pasta or pastry? Are you curious to find out whether the gluten in wheat, spelt, rye and barley is your friend or foe?

And most importantly, if you know you are better without wheat and gluten, do you need to avoid it completely, or can you have some occasionally?

If you want to know what are the lab testing options for wheat and gluten testing, then here is my lowdown on coeliac disease and gluten sensitivity testing in the UK. The power of testing will give you clarity to know what you can and cannot eat; and you will gain a greater understanding of how strict you need to be with your gluten-free diet. You will then know if you can ‘get away’ with eating that sneaky bit of sourdough or if a crumb of gluten is a total no-no and will make your health crumble for days afterwards.

Increasingly, more people are opting for a gluten-free diet or cutting out wheat, whether to better manage significant health issues such as autoimmune conditions or chronic fatigue, or simply to avoid bloating or support a weight loss journey. Supermarket ‘free-from’ aisles are now brimming with gluten-free bread, pasta, biscuits and cakes because so many people nowadays say that wheat and gluten trouble them.

Despite the significant rise in available gluten-free foods and the evidence that a gluten-free diet can help many people, following this diet strictly is hard, especially when catering for large families, eating out or travelling. It can also be expensive to buy gluten-free options. Therefore, you need to be sure how strict you need to be. And that means laboratory testing.

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Standard Coeliac disease testing

Historically, a gluten-free diet was only recommended for those people with a medical diagnosis of Coeliac disease. Coeliac disease is primarily a genetically acquired autoimmune reaction to wheat and gluten. It affects the gut lining of the small intestine and can flatten the villi of the small intestine, which can lead to significant gut malabsorption and nutrient deficiencies.

Symptoms of flattened villi, known as villous atrophy, can include yellow and greasy stools, diarrhoea, bloating and stomach pain. It may also look like fatigue, weight loss and a specific skin rash called dermatitis herpetiformis. Kids may be small with a round belly and may have mouth ulcers or poor tooth enamel. Coeliac disease was once seen as very rare, but it now affects 1% of the population (and 2% in Italy).

Coeliac disease can be easily tested through your GP via a simple blood test. You need to ask for an IgA Tissue Transglutaminase Coeliac test (tTG-IgA) and if it is for a young child, you also need to ask them to add on total IgA and Endomysial antibodies to prevent a false negative result.

You will also need to eat gluten every day for six weeks leading up to this blood test, as you can get a false negative result if you have not been eating enough gluten. Aim to consume the equivalent of at least ½ slice of toast or two biscuits daily during the six weeks leading up to the test.

The normal reference range tTG-IgA antibodies is 0-7 U/mL. A positive result is usually considered when the tTG-IgA is at 10 U/mL or above, and this suggests a high likelihood of coeliac disease, especially when accompanied by symptoms.

If a positive tTG-IgA is reported, it is recommended to get a referral to a gastroenterologist who will perform a biopsy on the small intestine to assess the damage to the villi in the gut from the gluten. You need to continue eating gluten until this biopsy is carried out and it can take months to set up this procedure. A positive tTG-IgA test with a negative biopsy is rare and the reality is that not many people want to wait that long. Many are keen to trial a gluten and wheat-free diet and are eager to start feeling better as soon as possible. As a result, they often accept that they must avoid gluten entirely going forward even without a definitive biopsy diagnosis. Genetic markers?

Coeliac disease is inherited, which means that it can be in your genetic blueprint and other members of your family might also have coeliac disease. If you get a negative coeliac result, but you still react to gluten, there is a blood or oral swab test to see if you carry certain HLA-DQ genetic alleles which can be arranged through a private GP or the NatureDoc clinical team.

95% of patients with coeliac disease hold the HLA DQ2 genetic SNP and about 5% carry HLA DQ8. This is a good test to do if you have members of the family with coeliac disease or a strong family autoimmune picture and want to know if you are likely candidate.

So even if you do not have coeliac disease (yet!) but you do carry this gene, then you may be more susceptible to developing coeliac disease or autoimmune conditions such as Hashimoto’s Thyroiditis or Type 1 Diabetes. You may also be more vulnerable to osteoporosis and gut malabsorption. Therefore, following a precautionary gluten-free diet may be a good idea.

Gluten sensitivity and neurological health

The Sheffield Institute of Gluten-Related Disorders (SIGReD), headed by Professors Marios Hadjivassiliou and Dave Sanders, researches how the diagnosis of Coeliac disease could be improved through increased recognition of the symptoms (which are not always connected to the gut), as well as identifying those patients who have non-Coeliac gluten sensitivity.

Dr Hadjivassiliou said in The Lancet that gluten sensitivity can be at times exclusively a neurological disease and there are often no gut symptoms at all. That means people can be displaying multiple symptoms of gluten sensitivity by having issues with their brain function such as brain fog, balance issues and neurological symptoms without any obvious gastric problems.

Gluten can drive brain inflammation, and it can deposit a type of plaque that interferes with proper communication between brain cells and may mimic a range of neurological illnesses such as ataxia, neuropathy, cognitive dysfunction, multiple sclerosis and Parkinson’s disease.

The team at SIGReD has suggested that theoretically, around 20% of the population is significantly affected by the ingestion of gluten.

Other gluten sensitivity tests

Gluten sensitivity testing has advanced so much, and the tests are now so sensitive that you can get an accurate test result even if you have been excluding gluten entirely for long periods of time. This means you do not need to start eating gluten again in the run-up to carrying out the tests. This takes away the fear and reluctance to resume eating wheat and gluten – just to do a test to check!

This gluten antibody testing has completely revolutionised our ability at NatureDoc to identify whether someone needs to be 100% gluten-free and whether it is just that or a broader problem with gluten that is triggering an autoimmune or inflammatory response.

These tests also help you work out if there are other grains that a person is reacting to, such as corn and rice, which are common ingredients in many gluten-free products.

If you are not keen to do blood tests, we can also look at gluten-related gut inflammation and gut permeability through stool testing, which can look at many aspects of gluten-sensitivity to include gut barrier dysfunction (leaky gut) and gluten autoimmunity activity.

This type of stool test not only tracks the entire gut microbiome and gut function, but also screens for gut permeability and immune activation with lipopolysaccharide antibodies (LPS), zonulin, tissue transglutaminase (tTG) and anti-gliadin antibodies – all vital information for connecting gut health and bloating to fatigue, joint pain, neurological symptoms or skin issues.

Urinary peptide testing

If you or your child feels drunk, woozy or has brain fog after ingesting gluten, then undigested or partially digested gluten peptides may be an issue.

Children who generate gluten peptides in their gut often seem somewhat ‘in their own little world’, they may be the type of child who never feels pain and may have speech and auditory integration issues. They may seem wired at night and struggle to sleep after ingesting gluten.

These kids often fixate on only eating gluten-heavy foods: dry cereal for breakfast, a sandwich for lunch and pasta for supper, day after day as if they need to eat it to get some sort of ‘fix’.

These peptides are incompletely digested tiny pieces of the gluten protein. If you have gut permeability, these gluten peptides (and sometimes casein in dairy products) pass through the gut lining to the bloodstream and up to the brain. They can react with opiate receptors in the brain, giving them a similar ‘high’ to that of opium. These compounds, known as neuropeptides, have been shown to interact with areas of the brain’s temporal lobes that are involved in speech and auditory integration. Neuropeptides also decrease the ability to feel pain and affect cognitive function.

Pure wheat allergy?

Many people are allergic to wheat and therefore need to be wheat-free rather than entirely gluten-free. Wheat is now one of the top eight food allergens, affecting millions of people globally. This can be tested as a sole IgE allergen or part of a wider panel of food and environmental allergens. It can be carried out either via a finger-prick blood test or a blood draw via a phlebotomist.

Food intolerance testing

Some people do not experience an immediate reaction to eating wheat and gluten after ingestion. It can take up to 72 hours to experience the negative effects of gluten. IgG testing is available to those with more niggly low-grade reactions to gluten and other foods. These were given a bad rap many years back, but the technology for these tests is now much more accurate.

Delayed food intolerance reactions are usually less dramatic than an allergy and can often be managed more easily than a pure IgE allergy or autoimmune response. We frequently see a positive IgG response in children who also experience a regular sore tummy, wheezing, itchy skin and/or mild learning difficulties or processing issues.

Often, these intolerances can be managed by taking a digestive enzyme supplement at the same time as consuming the gluten or wheat-based food to help break down some of the provoking proteins, and this can alleviate some of the gastric symptoms associated with eating wheat and gluten.

Case study – how gluten-sensitivity can be missed

Toby, a teenage boy diagnosed with type 1 diabetes, had also suffered from extreme gut problems since the age of 7. For 3 or 4 years he had missed a great deal of school due to fatigue and brain fog associated with these gut problems. He had repeatedly tested negative for Coeliac disease. When we carried out the antibody testing, he showed four raised antibodies to gluten and wheat including Transglutaminase-2 IgG, which attacks the gut in a similar way to Coeliac disease but would not have been tested through his diabetes team or GP.

Within a month or so of adopting a strict gluten-free diet, his gut, energy and brain fog symptoms disappeared. He did try one week back on gluten and suffered for three weeks afterwards, so he is now convinced he does need to remain on this gluten-free diet.

Round up

Most people can eat wheat and gluten without any problems, and foods containing these ingredients can provide valuable nutrition. However, if eating wheat and gluten is causing havoc on your healt,h it might be coeliac disease; but very often it can be another kind of food sensitivity or reaction.

Navigating the testing options for coeliac disease, gluten or wheat sensitivity can be complicated, and the NatureDoc clinical team are there for you to work out which tests are best for you to carry out. We can also help you interpret these results and help you find ways to feed yourself a nutritious diet – even if it needs to be gluten-free.

NB. This is an update of a post originally published in July 2015.

How to sort the ‘wheat from the chaff’ with wheat and gluten sensitivity tests

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Standard Coeliac disease testing

Gluten sensitivity and neurological health