IBS is a functional digestive system disorder, so nutrition plays a crucial role in the treatment. The influence of diet on IBS has not yet been adequately examined by controlled clinical studies, but many have their own subjective theories about which foods they can and cannot tolerate. There are inconsistencies and sometimes also incorrect information about the correct nutrition if you have IBS.
About every second irritable bowel patient believes that they have a certain food allergy or intolerance, although this often can’t be medically proven. More than 60 percent of those affected restrict their diet based on their own suspicion of an allergy or intolerance. This can result in** malnutrition.**
There is hope with current findings on fermentable carbohydrates, so-called FODMAPs. If you reduce these FODMAPs in your diet, the symptoms of many sufferers are alleviated. It’s also important to eat under calm, mindful circumstances.
What kind of diet works well with IBS?
With IBS, it is worthwhile to put your own diet to the test. Nutrition protocols with a symptom diary are good for this. If you note over a certain period which foods you eat and how you feel afterwards, this can provide valuable information for a balanced individual diet for IBS. Irritable bowel patients have a sensitive digestive system, which is why a careful diet is recommended. It is not only relevant what you eat but also how, when and where. The following general information should be observed in the diet:
- **Small meals: **don’t eat large portions at once
- **Mindful eating: **slow eating, conscious chewing, no distractions
- **Hydration: **drink enough
- **Alcohol, tea and coffee: **reduce alcoholic beverages, coffee and black/green tea as much as possible
- **Mild food: **avoid spicy, very salty, sweet or fatty foods
What does a low-FODMAP IBS diet look like?
FODMAPs are special sugars (carbohydrates) found in certain foods. FODMAPs include non-resorbable fermentable oligo-, di- and monosaccharides and (a) polyols, which are mostly found in foods containing gluten. About a third of patients suffering from IBS are also likely to be affected by FODMAP sensitivity. FODMAPs are insufficiently absorbed (resorbed) into the blood through the intestinal wall and are therefore fermented by the bacteria in the colon in the event of an oversupply. This leads to the formation of gases.
In addition, FODMAPs have an osmotic effect, which means that they draw water into the intestine, which in addition to the formation of gas leads to irritation of the intestine. The interaction of these factors can lead to typical irritable bowel symptoms such as bloating, so a low-FODMAP diet can help to alleviate symptoms. Since the low-FODMAP diet is mostly low in fiber, it is recommended to include non-fermentable fiber in the diet, such as psyllium.
How can you deal with food intolerances and carbohydrate malabsorption (lactose, fructose or sorbitol) with IBS?
Food intolerance is a major nutritional challenge with IBS. If there are indications of intolerance to certain foods, these should be diagnosed with a qualified doctor. After the intolerance has been confirmed, an individual irritable bowel-friendly diet can be put together.
With so-called carbohydrate malabsorption, certain sugars (carbohydrates), such as lactose, cannot be broken down properly in the intestine and are therefore poorly absorbed into the body via the intestinal wall. This is the case, for example, with lactose intolerance and fructose intolerance. An H2 breath test can be carried out by a doctor, for example, to clarify carbohydrate malabsorption. This gives indications of an insufficient intake of carbohydrates such as lactose, fructose or sorbitol in the intestine. If malabsorption is found, certain carbohydrates can be omitted in the** irritable bowel diet** (elimination diet), which can alleviate IBS symptoms.
Should an irritable bowel-friendly diet be wheat and gluten free?
People who are suffering from celiac disease (gluten intolerance) in most cases have not been able to tolerate products containing wheat gluten since childhood. Gluten is part of many common types of grain, including, for einkorn, wheat, rye, barley, spelt, emmer and einkorn.
People who have celiac disease lack certain enzymes in the intestine that help digest wheat protein. They do not have an allergy to wheat, but due to their intolerance they cannot digest certain substances, similar to people with lactose intolerance. If you still consume these substances anyway, this can sometimes lead to a dangerous reaction. With celiac disease, the intestines can be sustainably damaged by improper nutrition.
In addition to gluten intolerance, in rare cases there are people who develop symptoms directly from components of the wheat or via another mechanism. The extent to which wheat allergy or non-celiac non-wheat allergy sensitivity play a role in IBS has not yet been clearly clarified.
What role does wheat allergy play in an irritable bowel-friendly diet?
A wheat allergy causes a reaction to various wheat proteins such as
- Amylase trypsin inhibitors (ATIs)
- Lipid transfer protein
Some of these proteins are also contained in wheat gluten, so that after an allergy has been proven by an allergist (e.g. by a blood test [IgE], a skin prick test or by dietary methods), products containing gluten and wheat should be dispensed with. However, many irritable bowel patients report the success of a wheat and gluten-free diet even without evidence of a wheat allergy, because they presumably suffer from wheat sensitivity.
Is non-celiac, non-wheat allergy wheat sensitivity related to IBS?
Although both wheat allergy and celiac disease may have been excluded, intolerance to wheat components may still exist. In this case, this is referred to as wheat sensitivity, where a close connection with IBS is assumed. To date, however, there are no diagnostic tests for wheat sensitivity, so that the diagnosis, like IBS, is an exclusion diagnosis.
It is believed that gluten itself is not responsible for non-celiac, non-wheat allergy, and wheat sensitivity. Instead, two wheat components are suspected to trigger the hypersensitivity reaction, both of which usually occur together with gluten.
On the one hand, these are the so-called amylase trypsin inhibitors (ATIs), which can lead to a hypersensitivity reaction via the innate immune system. On the other hand, new research results suggest that some people are sensitive to the so-called FODMAPs. A recent study showed that the symptoms of irritable bowel patients who were excluded from celiac disease improved more with a low-FODMAP diet than with a gluten-free diet. This has prompted rethinking of nutrition for those who have irritable bowel syndrome.
Can I have an IBS-friendly diet if I react sensitively to wheat?
If wheat allergy and celiac disease have been ruled out and you still experience irritable bowel symptoms after eating wheat, many sufferers eliminate wheat from their diet. In this case, it is worthwhile to accompany the diet with a **symptom diary **(food diary) and possibly to integrate wheat into the diet in a targeted manner and observe the provoked symptoms (re-exposure). This is the only way to find out whether the wheat is really responsible for the symptoms.
About one in five people who experience symptoms with a wheat-free diet are not sensitive to wheat itself, but rather to FODMAPs. FODMAPS are not only found in various types of grain, but also in pods, fruits and vegetables. For this reason, if you have irritable bowel syndrome, it may be worthwhile to follow the low-FODMAP diet.
How do I recognize food intolerances with an irritable bowel-friendly diet?
It’s not always easy to identify food intolerances. However, it’s important not to lose the courage to form hypotheses about the intolerance. Many irritable bowel sufferers tend to make their diets very one-sided for fear of discomfort. This poses the risk of an unbalanced diet. For example, patients report that they have only eaten zucchini and rice for weeks for fear of symptoms.
Many incompatibilities become apparent as soon as the food is consumed and are therefore easy to recognize. However, other individual intolerances are more subtle and only show up at a clear time interval. Certain foods, such as FODMAPs, stay in the colon for two to three days before causing discomfort. In order to identify such intolerances, it helps to keep a symptom diary (food diary) for a limited time. This is the only way to recognize personal intolerances. Because unlike for many food allergies, no diagnostic tests are available for** food intolerance**.
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