Wheat, Gluten and Leaky Gut: Is Bread Really Making Your Gut Leaky?
Bread is the new smoking. At least that’s the impression you get scrolling through Instagram, podcasts and wellness blogs. Gluten supposedly punches holes in your gut, fuels inflammation throughout your body and, while it’s at it, causes belly fat, brain fog and bad moods. At the centre of it all is almost always the same buzzword: leaky gut. A widely read 2013 HuffPost article, ‘This Is Your Gut on Gluten’, by functional medicine doctor Amy Myers, bestselling author of ‘The Autoimmune Solution’, sums up this view pretty well. But what does the science actually say? We took a close look at the studies, including those published since 2013.
Key points at a glance
- In healthy people, bread does not make the gut permanently leaky. In the lab, gluten can briefly open the gut barrier, but a hard workout does the same.
- For people with coeliac disease, gluten really is harmful. Coeliac disease affects around one in a hundred people.
- Many people who don’t tolerate wheat well react to fructans rather than gluten. Bread made with a long fermentation is often easier for them to digest.
- If you have symptoms, get tested for coeliac disease first and only then cut out gluten. Otherwise the test may give a false negative result.
The accusation: gluten makes your gut leaky
Hardly a month goes by at our studio without someone telling us during their warm-up that they’ve ‘cut out gluten’ and feel like a new person. Usually this is followed by the explanation you also find in articles like the HuffPost piece: gluten opens up the gut wall, undigested particles get into the bloodstream and the immune system then runs permanently at full throttle.
The chain of argument goes roughly like this: gluten releases zonulin, zonulin opens the gut wall, foreign substances enter the blood, the immune system sounds the alarm. Myers adds further points. In summary, she argues:
- Coeliac disease and gluten intolerance have increased sharply over the past 50 years.
- Today’s wheat is not the wheat our parents ate. Cross-breeding has made around five per cent of its proteins new, and wheat is also chemically altered so that it can be mixed into almost any processed food, which triggers strong immune reactions.
- In sensitive people, gluten releases zonulin, which breaks open the connections between gut cells. Toxins, microbes, food particles and antibodies then enter the bloodstream and later attack the skin, thyroid or brain.
- The best test is to cut out gluten for 30 days, because your body knows better than any lab test. Her closing advice: if in doubt, give it up completely.
That sounds convincing. And there is a grain of truth in much of it. Myers writes from her experience as a doctor, and many of her patients probably did feel better without gluten. Since her article appeared in 2013, however, research has moved on considerably, and some points can now be explained differently. The key question is not whether the individual steps can be demonstrated in the lab, but whether the whole chain holds up in healthy people who eat bread, pasta and Bircher muesli as part of a normal diet. Let’s look at the points one by one.
What is ‘leaky gut’ anyway?
The lining of your gut is a remarkable structure: a single layer of cells, protected by a layer of mucus and guarded by immune cells. Between the cells sit so-called tight junctions, a kind of zip that controls what may pass between the cells and what may not.
The important thing is that this barrier is never completely sealed, and it isn’t meant to be. It opens and closes constantly, depending on what’s happening in your gut. A certain degree of permeability is therefore normal. It can be measured, for example, with sugar tests: you drink certain types of sugar and your urine is then tested to see how much has passed through the gut wall.
It is well established that the gut barrier becomes more permeable in conditions such as coeliac disease, inflammatory bowel disease or severe burns. However, a distinct ‘leaky gut syndrome’ does not exist as a diagnosis in conventional medicine. Michael Camilleri of the Mayo Clinic reviewed the evidence in 2019 in the journal Gut. His conclusion: the popular claims about leaky gut need to be confirmed before people cut out foods or buy supplements because of it. And so far, no gut disease has been cured simply by sealing the barrier again.
Permeability is therefore more of a symptom than a cause. That’s an important distinction when asking whether a single food is to blame.
Zonulin: the molecule the whole story is built on
Zonulin was described in the early 2000s by the group led by coeliac researcher Alessio Fasano. It acts as a kind of door opener for the tight junctions. Fasano himself sees it as a central mechanism in inflammation and autoimmune diseases, especially coeliac disease.
The studies that gluten critics like to cite do exist:
- A lab study from 2006 exposed tissue samples from the small intestine to gliadin. In coeliac patients, this led to sustained zonulin release and markedly increased permeability. In people without coeliac disease, by contrast, zonulin release was only limited and temporary, and permeability never reached the level of the coeliac tissue.
- A follow-up study from 2015 repeated the experiment with biopsies from four groups. The result quoted in many blogs: gliadin increased permeability in everyone, including the healthy controls. The effect was strongest in active coeliac disease and in people with gluten sensitivity.
Sounds like a clear verdict against gluten. Look more closely, though, and the picture becomes far more nuanced. In the follow-up study, just five to six tissue samples per group were examined. The gliadin was pre-digested and applied directly to a piece of gut lining in a measuring chamber, and measurements were taken over two hours. That is valuable basic research, but something completely different from a slice of bread and butter travelling through an intact gut along with other foods. And a brief, reversible opening of the tight junctions is not the same as damage. Exactly the same thing happens in your gut during a hard workout.
On top of that, there is a real measurement problem. Many labs offer zonulin tests on blood or stool to detect ‘leaky gut’. In 2018, however, a research group from Leipzig, which included Fasano himself, showed that a widely used commercial zonulin test does not detect actual zonulin at all, but other, related proteins. So if someone presents you with a raised zonulin level as proof of a leaky gut, a healthy dose of scepticism is in order. Similar caution applies to many home tests sold online, as we have already shown in our article on lifestyle genetic tests.
Coeliac disease, wheat allergy, sensitivity: three different issues
When people talk about gluten, they often lump together three very different things.
Coeliac disease is an autoimmune disease. In genetically predisposed people, gluten triggers an immune reaction that damages the lining of the small intestine. Around 0.7 to 1.4 per cent of people worldwide are affected, depending on whether diagnosis is based on blood tests or biopsies. For them, a strictly gluten-free diet is not a lifestyle choice but a treatment. Here the science is clear.
Myers is right that coeliac disease has become more common. Researchers at the Mayo Clinic compared blood samples from US servicemen taken between 1948 and 1954 with samples from today. Back then, 0.2 per cent had undiagnosed coeliac disease; today it is 0.8 to 0.9 per cent, around four times as many. Why this is the case, however, remains unclear. The authors themselves mention, among other things, changing patterns of infection in childhood, the so-called hygiene hypothesis. The study does not show that wheat has changed.
It is also true that people with coeliac disease produce antibodies against tissue transglutaminase, an enzyme produced by the body, and are more likely to have other autoimmune diseases, such as type 1 diabetes or thyroiditis.
Wheat allergy is a classic allergy to wheat proteins, which can cause skin reactions, breathing difficulties or, in rare cases, anaphylactic shock.
Non-coeliac gluten or wheat sensitivity is the big grey area. It refers to people who experience symptoms after eating wheat even though coeliac disease and allergy have been ruled out. Nobody seriously doubts that these symptoms are real. The open question is whether gluten really is the trigger. The studies paint a surprising picture:
- In 2011, an Australian double-blind study showed that gluten can cause symptoms in people without coeliac disease. However, the same research group repeated the experiment in 2013 with a diet low in so-called FODMAPs, poorly digestible carbohydrates that ferment in the gut. Suddenly they no longer found any specific effect of gluten.
- In a Norwegian study from 2018, 59 people who described themselves as gluten-sensitive were given muesli bars containing gluten, fructans or neither, without knowing which. Fructans, carbohydrates that are also found in wheat, caused significantly more bloating and symptoms than gluten. On average, gluten was no different from the placebo.
- An analysis of ten double-blind studies with a total of 1,312 adults concluded in 2017 that only around 16 per cent of supposedly gluten-sensitive people actually reacted specifically to gluten. Around 40 per cent had symptoms that were just as strong or even stronger on the placebo. Experts call this the nocebo effect: if you expect something to harm you, you often feel it too.
That doesn’t mean it’s all in the mind, though. A Columbia University study in 2016 examined 80 people with self-reported wheat sensitivity. They showed raised markers of damage to gut cells and of immune activation, which improved on a wheat-free diet. One candidate for this is a group of proteins called amylase-trypsin inhibitors (ATIs). These are the wheat plant’s defences against pests, and in the lab they activate the innate immune system. They are not part of gluten.
The honest summary: there is a group of people who react badly to wheat, and in some of them measurable changes can be detected. But gluten is probably the real culprit less often than its reputation suggests. That’s why many researchers now prefer to speak of wheat sensitivity rather than gluten sensitivity.
Is modern wheat to blame?
‘We are not eating the wheat our parents ate’ is probably the most quoted line from Myers’ article. Through breeding and cross-breeding, today’s wheat supposedly contains new, unknown proteins, which is why it is so poorly tolerated.
Myers is not alone in this view. It was popularised above all by the bestseller Wheat Belly (2011, published in German as Weizenwampe) by US cardiologist William Davis. The book describes modern wheat as a genetically modified fattening food whose protein fragments are said to be as addictive as a drug and to make you hungry. Researchers from Maastricht University and Rothamsted Research examined these claims in 2013. Their conclusion: the claims about addiction and overeating cannot be substantiated. On the contrary, wholegrain wheat in normal amounts is associated with less type 2 diabetes, less heart disease and better weight management. The only thing Wheat Belly gets right is that highly processed white bread makes blood sugar rise quickly. But that applies to many refined starchy foods and is more an argument for wholegrain than against wheat.
In 2020, the Leibniz Institute for Food Systems Biology in Freising, Germany, examined whether today’s wheat really contains more gluten. The researchers grew 60 wheat varieties that were popular in Germany between 1891 and 2010, all under the same conditions. The result: gluten content has remained the same over 120 years. Modern varieties actually contain slightly less protein and less gliadin, precisely the part of gluten that is considered the main trigger in coeliac disease. The share of the second gluten component, glutenin, has risen slightly instead. The weather in each growing year had a greater influence on gluten content.
And the ‘five per cent new proteins’? The study Myers cites for this examined plants created in the lab by fusing cells from bread wheat and a wild grass. This cannot be applied to the varieties your bread is baked from.
Chemically modified gluten does exist, too. This involves treating gluten with acid so that it dissolves in water and can be mixed into processed foods or cosmetics as a binding agent. But that is not a property of ‘today’s wheat’; it is a special additive. A few people have developed an allergy to it even though they tolerate normal wheat without any problems. A real but very limited problem with this additive, and no argument against bread and butter.
What has actually changed over recent decades is mainly how much wheat we eat and in what form: as sliced white bread, croissants (Gipfeli), pizza, biscuits, snacks and processed foods, often several times a day. Whether that’s a problem, however, has less to do with gluten than with whatever else is in these products and what’s missing from your plate as a result.
Oats, sourdough and spelt: which are easier to digest?
Whether bread is easy to digest depends not only on the grain but also on how it is processed. In the German-speaking fitness world, too, ‘go gluten-free’ is a popular tip. One example is the article ‘Gluten ist nicht gleich Gluten’ (‘Not all gluten is the same’) by Wolfgang Unsöld of YPSI from 2017. Unsöld writes from many years of experience as a trainer, and the article makes some interesting points. For some of its claims, though, it’s worth looking at the current evidence, especially where people with coeliac disease are concerned.
Oats: here the title is right. Gluten really is an umbrella term for various storage proteins. In wheat these are gliadin and glutenin; rye, barley and oats each have their own variants. The oat protein avenin is far less problematic. A 2017 meta-analysis found no evidence that pure, uncontaminated oats cause symptoms, gut damage or antibodies in people with coeliac disease. The quality of the data was low, however, and a small proportion of those affected cannot tolerate even pure oats. Regular oats are also often contaminated with wheat. Anyone with coeliac disease should therefore choose certified gluten-free oats and introduce them in consultation with their doctor.
Sourdough: caution is needed here. The YPSI article states that 8 out of 10 people with coeliac disease can eat sourdough bread without noticeable symptoms. The studies available on this paint a more nuanced picture. In an Italian study, people with coeliac disease were given, for 60 days, baked goods made from flour that had been almost completely freed of gluten using specially selected lactic acid bacteria and fungal enzymes. Only the fully broken-down flour with less than 10 ppm residual gluten was safe. The two participants whose baked goods still contained around 2,500 ppm gluten had no symptoms but nevertheless developed marked damage to the gut lining. That is exactly the point: in coeliac disease, ‘no symptoms’ does not mean ‘no damage’. A normal sourdough loaf from the bakery is off limits for people with coeliac disease.
Long fermentation: this is where you can make a real difference. For people without coeliac disease who get bloated after eating wheat, on the other hand, there is good news. Researchers at the University of Hohenheim showed that letting dough rest for more than four hours can reduce the FODMAP content of bread, mainly fructans, by up to 90 per cent. The method of preparation mattered more than the type of grain. Spelt, emmer and einkorn did not automatically perform better. Since fructans, as described above, are more often the trigger than gluten, many people would do well to switch first from quick-baked sliced white bread to long-fermented bread from an artisan baker.
One more point from the YPSI article no longer holds up: the claim that today’s flour contains many times more gluten than 50 years ago is refuted by the study of 60 wheat varieties over 120 years described above.
The psychoneuroimmunology perspective
Experts in clinical psychoneuroimmunology (cPNI) make a particularly detailed biochemical case. This approach views the nervous, hormonal, immune and metabolic systems as one interconnected whole. One of its best-known proponents is the Dutch biochemist and physiologist Leo Pruimboom, who played a key role in founding clinical PNI and now works with the University of Granada, among others. He takes a very critical view of gluten.
In a review published in 2013, Pruimboom and researcher Karin de Punder describe two ways in which grains could promote inflammation. First, through gliadin, which, as described above, can open the gut barrier via zonulin. Second, through a defensive protein in wheat, a so-called lectin, which in the lab can likewise make the gut wall more permeable and activate immune cells. Their hypothesis: these mechanisms could contribute to chronic, low-grade inflammation and autoimmune diseases not only in people with coeliac disease but in many others too. Behind this lies an evolutionary idea: grains are a relatively recent food for humans, and our immune system may not yet have fully adapted to them.
The biochemical mechanisms are well described and help explain why gluten has such a bad reputation in PNI. The authors themselves point out, however, that most of the evidence comes from cell and animal studies and that well-designed studies in humans are still lacking. The double-blind studies and long-term observations in this article have so far shown no clear harm from gluten in healthy people, but they also don’t rule out the possibility that some people are more sensitive than others. Our conclusion: PNI provides valuable explanatory models and good reasons to look more closely, especially in autoimmune diseases or chronic inflammation. But the evidence is not yet strong enough for a blanket recommendation for everyone.
What does going gluten-free do if you’re healthy?
That leaves the question of why so many people feel better without gluten. A Danish study offers a rather elegant answer. Sixty healthy adults followed a low-gluten diet (2 g per day) and a high-gluten diet (18 g per day) for eight weeks each, with the same amount of fibre. During the low-gluten phase, they had less bloating and their microbiome changed. However, the researchers attribute this not to the missing gluten but to the change in the type of fibre. If you cut out wheat, you also eat fewer fructans and more of something else.
On the other hand: an analysis of more than 100,000 people from two large American long-term studies found no link between gluten intake and heart attacks over 26 years. When the researchers took into account how much refined white flour participants ate, more gluten was even associated with a slightly lower risk, probably because it then came mainly from wholegrains. The authors therefore warn against recommending a gluten-free diet to healthy people, as valuable wholegrain products are easily lost in the process. By the way, we recently published a separate article on the role of fibre for your gut.
And in sport? In sports nutrition, too, gluten-free has long been a trend. A study of 13 cyclists without coeliac disease gave the athletes either bars containing 16 g of gluten per day or gluten-free bars for one week, without them knowing which. There was no difference in time-trial performance, gastrointestinal symptoms, wellbeing, inflammatory markers or a marker of gut damage.
The fact that many people still feel better is not a contradiction. People who give up gluten often automatically eat fewer processed foods, pastries and snacks, cook more for themselves and pay more attention to their diet. That alone can make a big difference. It’s just that the missing gluten doesn’t deserve the credit.
Glutamine: our experience and what the studies say
When clients come to us with digestive problems, our nutrition coaching often brings in a supplement we have had good experiences with: glutamine. But because experience alone isn’t enough for us, we always look at the evidence on supplements as well. One tool we use a lot for this is Examine, an independent database that evaluates studies on supplements and does not sell any supplements itself.
Glutamine is an amino acid that your body normally produces in sufficient amounts. It is, however, the preferred fuel for the cells of the gut lining and for immune cells. In severe injuries, burns or illness, the need rises so sharply that glutamine is considered ‘conditionally essential’. This is exactly where its effect on the gut barrier is best documented: in his leaky gut review, Camilleri explicitly cites glutamine as an example of how increased permeability can be reversed in severe burns. According to Examine, however, research has not been able to confirm the often-promised effect on muscle building in healthy people.
Two studies are particularly interesting for our topic:
- IBS after a gut infection: In a double-blind study published in 2019 in the journal Gut, 106 people with irritable bowel syndrome (IBS) and demonstrably increased gut permeability received either 5 g of glutamine three times a day or a placebo for eight weeks. In the glutamine group, symptoms improved in around 80 per cent, compared with just under 6 per cent in the placebo group. Permeability returned to normal only with glutamine. An impressive result, but with limitations: the participants were very carefully selected, and critics pointed out that the whey protein placebo could itself have caused symptoms. Larger studies are still needed.
- Training in the heat: A study of ten men showed that glutamine taken two hours before a run in the heat reduced exercise-induced gut permeability, and the higher the dose, the stronger the effect. However, it had no measurable effect on gastrointestinal symptoms.
Our assessment: glutamine is one of the few supplements for which there is a plausible mechanism and some good early studies on the gut barrier. That is consistent with what we see in practice: many clients with digestive complaints find that their symptoms improve. One possible explanation is that gut cells use glutamine as their main fuel and are constantly renewing themselves. So far, however, this effect has mainly been studied in people with serious illnesses, and our observations from coaching are not a controlled study. The placebo effect also plays a big role in digestive complaints, as we saw above.
How much glutamine makes sense is something we discuss individually in our nutrition coaching. In the IBS study above, it was 5 g three times a day, i.e. 15 g per day. According to Examine, very high amounts can raise ammonia levels in the blood.
Important: glutamine is no substitute for a medical assessment. It makes sense once coeliac disease and other causes have been ruled out. Anyone with liver or kidney disease should only take glutamine after consulting their doctor. And by the way: whey and casein protein are naturally rich in glutamine. If you eat enough protein, you’re already getting quite a bit of it.
What does this mean for you and your training?
This is where it gets slightly ironic: if there’s one thing that has been shown to make the gut temporarily more permeable in healthy people, it’s not your breakfast toast but your training. This has been known for years in endurance athletes, especially during long, intense sessions and in the heat. A study of trained strength athletes showed that even a single hard strength session increases gut permeability, more so in men than in women. Nobody would conclude that squats should be banned as harmful to health. Your gut is designed to cope with brief openings like these and to close up again.
On the most important practical advice, we take a slightly different view from the HuffPost article. Myers recommends cutting out gluten for 30 days and listening to your body. How you feel matters, but it shouldn’t come first. Without testing beforehand, this approach can make a coeliac diagnosis harder. And as the double-blind studies above show, many people feel better or worse even when they don’t know whether they’ve eaten gluten. The same applies to the self-test with a gluten-free week suggested in the YPSI article.
In practice, this means:
- If you regularly have symptoms after eating bread and pasta, get tested for coeliac disease before you cut out gluten. This is the most important point in this article. The blood test is only reliable as long as you are still eating gluten. If you have already been gluten-free for a few weeks, the test may give a false negative result. So before the test, you should go back to eating gluten regularly, in consultation with your doctor.
- Think about fructans and other FODMAPs. If you get bloated not only from wheat but also from onions, garlic or pulses, gluten is probably not the main suspect. A food diary and a professionally supervised elimination diet will help more here than a blanket ban on gluten. Your gut flora also plays a big role.
- Don’t waste your money on expensive zonulin or ‘leaky gut’ tests. Their reliability is questionable, at least for the common test kits.
- If you feel better without wheat, that’s absolutely fine. But replace it with high-fibre alternatives such as oats, buckwheat, millet, quinoa, potatoes or, if you tolerate them well, pulses, rather than gluten-free white bread and biscuits from the free-from aisle. Gluten-free junk food is still junk food.
- Eat fermented foods regularly. Instead of only thinking about what to cut out, it’s worth looking at what you can do for your gut. In a Stanford University study, 36 healthy adults spent ten weeks eating either lots of fermented foods such as yoghurt, kefir, sauerkraut, kimchi or kombucha, or a particularly high-fibre diet. In the fermented-food group, the diversity of gut bacteria increased, and the larger the portions, the greater the increase, while numerous inflammatory markers in the blood fell at the same time. Gut permeability was not measured, and the study was small. But an extra glass of kefir or a portion of sauerkraut is a simple and inexpensive step.
Conclusion
- Gliadin from gluten can briefly open the gut barrier in the lab, even in people without coeliac disease. In healthy people, however, this effect is small and temporary. There is no evidence that bread causes a permanently leaky gut in them.
- For people with coeliac disease, gluten really is harmful, and a strictly gluten-free diet is essential for them. Coeliac disease affects around one in a hundred people.
- Many people who describe themselves as gluten-sensitive do not react to gluten in blinded tests, but rather to fructans or other components of wheat. In some of them, however, real, measurable changes can be detected.
- Modern wheat does not contain more gluten than old varieties. What has changed is mainly how much wheat we eat and in what form. Bread made with a long fermentation contains far fewer fructans and is often better tolerated, but it is just as off limits for people with coeliac disease as any other wheat bread.
- Cutting out gluten without having coeliac disease does not automatically benefit your health, and you risk missing out on valuable wholegrain products and fibre. In sport, too, going gluten-free brings no performance advantage.
- There is a plausible mechanism and some good early studies on glutamine and the gut barrier, mainly in serious illnesses and in IBS after a gut infection. Glutamine is no substitute for a medical assessment.
So you don’t need to ban bread out of fear of a leaky gut. If you have symptoms, take them seriously and get them checked, but in the right order: test first, then cut out. And if you feel better eating less wheat, that’s perfectly fine. Just make sure there’s something better on your plate than gluten-free biscuits. And if you’d like to get rid of a few more nutrition myths while you’re at it, here are the 10 most common nutrition misconceptions we come across at Personalworkout.
Frequently asked questions about gluten and leaky gut
Can you test for leaky gut?
In research, gut permeability is measured with sugar tests. The zonulin tests offered by many labs, on the other hand, are of little value, because a widely used test does not even detect actual zonulin. There is no recognised diagnosis of ‘leaky gut syndrome’.
Is spelt easier to digest than wheat?
Not automatically. Spelt also contains gluten and is just as off limits for people with coeliac disease. When it comes to bloating, what matters most is how the bread is baked. A long resting time for the dough greatly reduces the fructan content, whether the bread is made from wheat, spelt, emmer or einkorn.
Is sourdough bread safe for people with coeliac disease?
No. Normal sourdough bread from the bakery still contains gluten. In studies, only special baked goods made from flour that had been almost completely freed of gluten proved safe. In coeliac disease, gluten can damage the gut lining even when you don’t notice any symptoms.
Can people with coeliac disease eat oats?
Pure, certified gluten-free oats are well tolerated by most people with coeliac disease. Regular oats, however, are often contaminated with wheat. Because a small proportion of those affected cannot tolerate even pure oats, oats should be introduced in consultation with a doctor.
Does a gluten-free diet help in sport?
Not in athletes without coeliac disease, based on current evidence. In a blinded study with cyclists, there was no difference in performance, gastrointestinal symptoms or inflammatory markers.
SOURCES
- Biesiekierski, J. R., Newnham, E. D., Irving, P. M., et al. (2011). Gluten causes gastrointestinal symptoms in subjects without celiac disease: a double-blind randomized placebo-controlled trial. American Journal of Gastroenterology, 106(3), 508–514. https://doi.org/10.1038/ajg.2010.487
- Biesiekierski, J. R., Peters, S. L., Newnham, E. D., Rosella, O., Muir, J. G., & Gibson, P. R. (2013). No effects of gluten in patients with self-reported non-celiac gluten sensitivity after dietary reduction of fermentable, poorly absorbed, short-chain carbohydrates. Gastroenterology, 145(2), 320–328. https://doi.org/10.1053/j.gastro.2013.04.051
- Brouns, F. J. P. H., van Buul, V. J., & Shewry, P. R. (2013). Does wheat make us fat and sick? Journal of Cereal Science, 58(2), 209–215. https://doi.org/10.1016/j.jcs.2013.06.002
- Camilleri, M. (2019). Leaky gut: mechanisms, measurement and clinical implications in humans. Gut, 68(8), 1516–1526. https://doi.org/10.1136/gutjnl-2019-318427
- Davis, W. (2011). Wheat Belly: Lose the Wheat, Lose the Weight, and Find Your Path Back to Health. Rodale. German edition: Weizenwampe.
- de Punder, K., & Pruimboom, L. (2013). The dietary intake of wheat and other cereal grains and their role in inflammation. Nutrients, 5(3), 771–787. https://doi.org/10.3390/nu5030771
- Denery-Papini, S., Bodinier, M., Larré, C., et al. (2012). Allergy to deamidated gluten in patients tolerant to wheat: specific epitopes linked to deamidation. Allergy, 67(8), 1023–1032.
- Drago, S., El Asmar, R., Di Pierro, M., et al. (2006). Gliadin, zonulin and gut permeability: effects on celiac and non-celiac intestinal mucosa and intestinal cell lines. Scandinavian Journal of Gastroenterology, 41(4), 408–419. https://doi.org/10.1080/00365520500235334
- Examine.com. Glutamine. https://examine.com/supplements/glutamine/
- Fasano, A. (2011). Zonulin and its regulation of intestinal barrier function: the biological door to inflammation, autoimmunity, and cancer. Physiological Reviews, 91(1), 151–175. https://doi.org/10.1152/physrev.00003.2008
- Ford, A. C., & Gibson, P. R. (2019). Efficacy of glutamine in postinfection IBS. Gut, 68(10), 1905–1906. https://doi.org/10.1136/gutjnl-2018-317438
- Greco, L., Gobbetti, M., Auricchio, R., et al. (2011). Safety for patients with celiac disease of baked goods made of wheat flour hydrolyzed during food processing. Clinical Gastroenterology and Hepatology, 9(1), 24–29. https://doi.org/10.1016/j.cgh.2010.09.025
- Hansen, L. B. S., Roager, H. M., Søndertoft, N. B., et al. (2018). A low-gluten diet induces changes in the intestinal microbiome of healthy Danish adults. Nature Communications, 9, 4630. https://doi.org/10.1038/s41467-018-07019-x
- Hart, T. L., Townsend, J. R., Grady, N. J., Johnson, K. D., Littlefield, L. A., Vergne, M. J., & Fundaro, G. (2022). Resistance exercise increases gastrointestinal symptoms, markers of gut permeability, and damage in resistance-trained adults. Medicine & Science in Sports & Exercise, 54(10), 1761–1770. https://doi.org/10.1249/MSS.0000000000002967
- Hollon, J., Puppa, E. L., Greenwald, B., Goldberg, E., Guerrerio, A., & Fasano, A. (2015). Effect of gliadin on permeability of intestinal biopsy explants from celiac disease patients and patients with non-celiac gluten sensitivity. Nutrients, 7(3), 1565–1576. https://doi.org/10.3390/nu7031565
- Junker, Y., Zeissig, S., Kim, S. J., et al. (2012). Wheat amylase trypsin inhibitors drive intestinal inflammation via activation of toll-like receptor 4. Journal of Experimental Medicine, 209(13), 2395–2408. https://doi.org/10.1084/jem.20102660
- Lebwohl, B., Cao, Y., Zong, G., et al. (2017). Long term gluten consumption in adults without celiac disease and risk of coronary heart disease: prospective cohort study. BMJ, 357, j1892. https://doi.org/10.1136/bmj.j1892
- Lis, D., Stellingwerff, T., Kitic, C. M., Ahuja, K. D., & Fell, J. (2015). No effects of a short-term gluten-free diet on performance in nonceliac athletes. Medicine & Science in Sports & Exercise, 47(12), 2563–2570. https://doi.org/10.1249/MSS.0000000000000699
- Molina-Infante, J., & Carroccio, A. (2017). Suspected nonceliac gluten sensitivity confirmed in few patients after gluten challenge in double-blind, placebo-controlled trials. Clinical Gastroenterology and Hepatology, 15(3), 339–348. https://doi.org/10.1016/j.cgh.2016.08.007
- Myers, A. (2013, 6 August). This is your gut on gluten. HuffPost. https://www.huffpost.com/entry/effects-of-gluten-on-the-body_b_3672275
- Pinto-Sánchez, M. I., Causada-Calo, N., Bercik, P., et al. (2017). Safety of adding oats to a gluten-free diet for patients with celiac disease: systematic review and meta-analysis of clinical and observational studies. Gastroenterology, 153(2), 395–409. https://doi.org/10.1053/j.gastro.2017.04.009
- Pronin, D., Börner, A., Weber, H., & Scherf, K. A. (2020). Wheat (Triticum aestivum L.) breeding from 1891 to 2010 contributed to increasing yield and glutenin contents but decreasing protein and gliadin contents. Journal of Agricultural and Food Chemistry, 68(46), 13247–13256. https://doi.org/10.1021/acs.jafc.0c02815
- Pugh, J. N., Sage, S., Hutson, M., Doran, D. A., Fleming, S. C., Highton, J., Morton, J. P., & Close, G. L. (2017). Glutamine supplementation reduces markers of intestinal permeability during running in the heat in a dose-dependent manner. European Journal of Applied Physiology, 117(12), 2569–2577. https://doi.org/10.1007/s00421-017-3744-4
- Rubio-Tapia, A., Kyle, R. A., Kaplan, E. L., et al. (2009). Increased prevalence and mortality in undiagnosed celiac disease. Gastroenterology, 137(1), 88–93. https://doi.org/10.1053/j.gastro.2009.03.059
- Scheffler, L., Crane, A., Heyne, H., et al. (2018). Widely used commercial ELISA does not detect precursor of haptoglobin2, but recognizes properdin as a potential second member of the zonulin family. Frontiers in Endocrinology, 9, 22. https://doi.org/10.3389/fendo.2018.00022
- Singh, P., Arora, A., Strand, T. A., et al. (2018). Global prevalence of celiac disease: systematic review and meta-analysis. Clinical Gastroenterology and Hepatology, 16(6), 823–836. https://doi.org/10.1016/j.cgh.2017.06.037
- Skodje, G. I., Sarna, V. K., Minelle, I. H., et al. (2018). Fructan, rather than gluten, induces symptoms in patients with self-reported non-celiac gluten sensitivity. Gastroenterology, 154(3), 529–539. https://doi.org/10.1053/j.gastro.2017.10.040
- Uhde, M., Ajamian, M., Caio, G., et al. (2016). Intestinal cell damage and systemic immune activation in individuals reporting sensitivity to wheat in the absence of coeliac disease. Gut, 65(12), 1930–1937. https://doi.org/10.1136/gutjnl-2016-311964
- Unsöld, W. (2017, 6 March). Gluten ist nicht gleich Gluten. YPSI. https://www.ypsi.de/blogs/ernaehrung/gluten-ist-nicht-gleich-gluten
- Wastyk, H. C., Fragiadakis, G. K., Perelman, D., et al. (2021). Gut-microbiota-targeted diets modulate human immune status. Cell, 184(16), 4137–4153. https://doi.org/10.1016/j.cell.2021.06.019
- Zhou, Q., Verne, M. L., Fields, J. Z., et al. (2019). Randomised placebo-controlled trial of dietary glutamine supplements for postinfectious irritable bowel syndrome. Gut, 68(6), 996–1002. https://doi.org/10.1136/gutjnl-2017-315136
- Ziegler, J. U., Steiner, D., Longin, C. F. H., Würschum, T., Schweiggert, R. M., & Carle, R. (2016). Wheat and the irritable bowel syndrome – FODMAP levels of modern and ancient species and their retention during bread making. Journal of Functional Foods, 25, 257–266. https://www.sciencedirect.com/science/article/abs/pii/S1756464616301463
- Study on ‘new proteins’ cited by Myers (somatic hybrids of wheat and wild grass): http://www.ncbi.nlm.nih.gov/pubmed/20130747
Challenge of the Month
What Clients Say
What You Get
