Over the past ten years, gluten has become the food to avoid. Influenced by social networks and stars who are fans of “gluten-free”, many consumers have chosen to ban it, convinced that it damages their intestine or makes their stomach swell. But a study published in The Lancet seriously qualifies this perception.
Gluten, wrongly accused by the majority of consumers
Led by Associate Professor Jessica Biesiekierski of La Trobe University, Australia and other British, Dutch and Italian scientists, this meta-analysis brought together more than 58 clinical studies conducted on nearly 4,000 participants.
Objective: to determine if gluten is really the cause of digestive symptoms in people who say they are “sensitive”, but do not suffer from celiac disease.
Researchers examined data on immune response, intestinal barrier, microbiota and psychological factors. Result: in the vast majority of cases, specific reactions to gluten were rare and variations in symptoms were minimal.
Additionally, in double-blind trials, nearly 70% of participants responded as much or more to a placebo than to the gluten itself. “Gluten has been wrongly demonized“, explains Professor Jessica Biesiekierski.
When FODMAPs disrupt our intestines
The study reveals that many of the symptoms attributed to gluten could actually come from other substances, including FODMAPs. These fermentable carbohydrates are naturally present in certain fruits, vegetables, legumes and grains. Work included in the meta-analysis showed that when people sensitive to gluten followed a diet low in FODMAPs, their symptoms improved, even after its reintroduction.
Researchers have also identified fructans, a particular type of FODMAP present in wheat, garlic or onion, as likely culprits for bloating.
“People with irritable bowel syndrome who think they are gluten sensitive respond similarly to gluten, wheat, and a placebo. specifies Jessica Biesiekierski. “This shows that the way we anticipate and interpret our gut sensations can strongly influence our symptoms.”
The expert evokes here a probable nocebo effect: when we expect to be sick, the brain amplifies the intestinal response. To confirm this bias, the researchers observed the brains of the volunteers using brain imaging. They found increased activation in areas of the brain related to pain and threat anticipation. The link between stress, emotions and digestion is thus strengthened.
“Not everyone needs to exclude gluten”
Consulted on the subject, dietitian-nutritionist Eva Vacheau confirms that this work supports what practitioners have been observing for several years. “It is true that gluten has been demonized a lot in recent years and not everyone needs to exclude it”she explains.
“The problem is that there are several different situations: true intolerance, sensitivity, and disorders linked to FODMAPs. And very often, patients do not differentiate between the three. We think we are intolerant to gluten when in fact, it is more a sensitivity to FODMAPs. These fermentable sugars cause gas, bloating and intestinal discomfort.”
Carbohydrates hidden in many foods
Additionally, FODMAPs are found in many foods. “It is found in wheat, but also in apples, pears, onions, legumes, dairy products and certain dried fruits. These are healthy foods, but they can ferment in the gut and cause pain.”
According to the dietician, certain pathologies can accentuate this sensitivity. “Some people suffer from SIBO, a bacterial overgrowth of the small intestine. For them, a small amount of FODMAPs is enough to cause severe bloating. Others have chronic low-grade inflammation, which manifests as digestive hypersensitivity.”
Do not ban all types of gluten
Finally, the quality of the gluten also matters, according to Eva Vacheau. “The gluten of modern wheat is digested less well than that of rye, spelled or ancient wheat” she notes. It is therefore important to adapt your diet, if you consider yourself sensitive, without falling into the excess of “gluten-free”.
Our expert therefore pleads for a personalized approach
: “Rather than avoiding gluten or excluding it completely, it is better to identify the real triggers. It is necessary to rebalance the intestinal flora, support the liver and adapt the diet to each person, according to their individual tolerance”.
The researchers of the study published in The Lancet
abound in this direction. They recommend, before avoiding gluten, to:
- Rule out celiac disease and wheat allergy;
- Improve the overall balance of the diet;
- And, if symptoms persist, try a low FODMAP diet before a temporary gluten-free trial supervised by a professional.
Because, according to their conclusions, gluten is only really problematic for a minority of people, and its systematic exclusion could on the contrary impoverish the diet and increase digestive stress.