In recent years, the supermarket rays have been overflowing with gluten -free products. Social networks are full of testimonials from convinced people that gluten ruins their digestion, their skin, their sleep, their life, sometimes. But behind this food trend, a question of size arises: is gluten really guilty, or is it not rather our brain that plays towers?
A series of recent studies sows doubt, with a small revelation as a bonus: in many people who think of digesting gluten badly, the symptoms would especially come … from the anticipation of these symptoms. In other words, a wedding effect, the nasty cousin of the placebo effect. And that track, science is starting to take it seriously seriously.
A gluten -free wave … but with a lot of misunderstandings
Gluten, really so harmful?
Gluten is only dangerous in some specific cases. It is toxic to people with celiac disease (intestinal), or about 1 % of the population in France, and problematic for those suffering from wheat allergy, much rarer. But for all the others then? Those who do not digest well, who bloak up, who feel tired after a piece of wand … Science struggles to prove that gluten is in question.
According to an analysis published in 2023 in the journal Nutrients (Van Gils et al.), The vast majority of people who say they are “sensitive to gluten” do not actually react to gluten when they are given their knowledge. In double -blind controlled trials (where neither patients nor researchers know if it is real or false gluten), only 16 to 18 % of subjects really react to gluten. The others … also react when they take nothing, or placebo.
The weight of belief: the wedding effect at work
In July 2025, a study by the Canadian University McMaster (Lancet Gastroenterology & Hepatology) followed 29 adults with irritable intestine syndrome (SII), all convinced of being sensitive to gluten. They gave them, in turn, bars containing gluten, whole wheat … or none of the two.
As a result, participants felt symptoms in all cases, including with gluten -free or wheat bars. Their body reacted to their conviction to eat gluten, not to gluten itself.
Same observation in the United Kingdom. A study conducted at the University of Leeds, published in June 2024 (gastroenterology), has shown that the only negative expectation of gluten was sufficient to cause abdominal, bloating and fatigue pain in patients with SII.
SII, Fodmaps, Ati… What if it was not (that) gluten?
What these studies also highlight is that gluten may be only a culprit among others. Wheat contains many other substances, such as fodmaps (fermentable carbohydrates) or amylase-trypsin inhibitors (ATI), which can irritate the intestine.
Researchers agree today to say that in some patients with irritable intestine syndrome, it would not be so much gluten that would be a problem … that the combination of certain components of wheat, digestive hypervigilance, and stress.
Yes, stress. Because the digestive system is directly connected to the brain, and the brain axis-maintenance can play formidable towers. Clearly, the more we fear a digestive reaction, the more the body is likely to trigger one.
Gluten: How do I know if I am intolerant?
What to do if you think you are sensitive to gluten
Before deleting everything, some simple and useful tips:
- Make a real medical assessment, with screening for celiac disease and wheat allergy.
- Explore the Fodmaps track, often in question in functional digestive disorders.
- Testing a global management of the SII, with nutritional support, relaxation, even cognitive behavioral therapy.
- Consult a dietitian-nutritionist, to avoid unnecessary deficiencies or diets.
Exclude gluten: false good idea
Deleting gluten without medical reason is not necessarily a good idea. According to a Harvard study (BMJ, 2017), people without celiac disease who follow a gluten -free diet can consume less fiber and more saturated fats, with a long -term impact on the intestinal microbiota.
In addition, an eviction regime can worsen digestive disorders if it is poorly conducted. And it can strengthen the fear of food, nourishing a vicious circle of restriction, anxiety, and symptoms.
NAMELY
In some people who think they are sensitive to gluten, it may be an imbalance in good bacteria in the intestine that causes symptoms, not gluten itself. Eating better or taking probiotics can sometimes help.
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