Ms. Buhmann, irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders. Nearly one in seven people is affected.

FODMAPs are cited as a possible cause for irritable bowel syndrome. Could you explain to us what FODMAPs are and in which foods they are particularly common?

The term "FODMAP" is the abbreviation for "Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols." These are specific short-chain carbohydrates, which include fructans, lactose, and fructose, for example. Many types of vegetables and fruits, such as cauliflower, garlic, and onions, as well as stone fruit, dried fruit, or apples, are high in FODMAPs. Wheat, rye, barley, as well as legumes, mushrooms, cashews, milk, and dairy products also have a high FODMAP content, as do honey and processed products with added sorbitol or fructose (e.g., in sports bars).

FODMAPs are not inherently unhealthy. Certain FODMAPs are good food for beneficial gut bacteria.

What is the problem with FODMAPs, then?

Even though FODMAPs sometimes even possess prebiotic properties and are good for the intestinal environment, those suffering from IBS react to FODMAP-rich foods with varying degrees of discomfort. Large amounts of FODMAPs cannot be digested, or only partially digested, in their small intestine. As a result, the sugars pass undigested into the large intestine and are fermented there by gut bacteria. This produces gases that stretch the intestinal wall, leading to pain. In addition, certain FODMAPs have an osmotic effect, meaning they draw water into the large intestine. The increased gas production and water accumulation lead to bloating, abdominal cramps, and diarrhea in people with irritable bowel syndrome, sometimes alternating with constipation.

People with IBS are recommended to follow an eating plan based on the FODMAP concept. What is the FODMAP concept and who developed it? Is it successful?

Scientists at Monash University in Australia discovered that certain short-chain carbohydrates can cause symptoms in sensitive individuals. They named these types of sugars FODMAPs. Based on their findings, they developed the "Low FODMAP diet," known as the "FODMAP concept." Using extensive analyses, the research team assigned foods to a simple color-coded traffic light system. This makes it easy to see which foods contain only a few FODMAPs in certain amounts (green), which have a medium FODMAP content (orange), and which foods are high in FODMAPs (red). The FODMAP concept is a three-phase nutritional program in which the FODMAP content of foods is taken into account.

Clinical studies by Monash University have proven the effectiveness of the FODMAP concept. FODMAP dietary therapy is scientifically recognized and recommended as an effective measure in the German S3 guideline for IBS. For about 75 percent of those affected by IBS, a FODMAP-adapted diet is successful and can significantly reduce symptoms and improve quality of life.

How is the FODMAP concept applied?

At the beginning, those affected avoid FODMAP-rich foods. This elimination phase lasts for four to a maximum of six weeks. This relatively strict phase serves to determine whether the change in diet alleviates the symptoms. It is important not to simply leave foods out, but to replace them with low-FODMAP alternatives, for example, kiwi instead of apple or carrots instead of green peas. As soon as symptoms improve significantly, foods with a medium or high FODMAP content are tested step-by-step for individual tolerance. This is the so-called tolerance discovery phase, also known as the reintroduction phase. This can vary in length and provides valuable insights into which foods, in what amounts, or in what combinations trigger symptoms. Based on personal experience, the transition to long-term nutrition, i.e., the third phase, is fluid. In the long term, the diet should be balanced and cause as few symptoms as possible, if any. However, one should not forget that other factors such as stress can trigger and intensify symptoms. Therefore, there are various treatment approaches, with the FODMAP nutritional concept playing a central role.

For getting started, good planning and the guidance of a nutrition professional are recommended. Professionals trained in the low-FODMAP diet can provide individual advice to those suffering from IBS. The FODMAP concept is not as complicated as one might assume at first. There are useful food tables and lists based on an easy-to-understand traffic light system, as well as the Monash FODMAP app as a valuable guide. And, of course, cookbooks with suitable recipe ideas and menu suggestions help to implement the diet in everyday life. The FODMAP concept is not a "diet" in the traditional sense, but rather a FODMAP-conscious way of eating that the whole family can join in with.

Is the FODMAP concept also suitable for vegetarians and vegans?

Even without meat or fish, this way of eating is easy to apply for ovo-lacto vegetarians. Vegans, however, should inform themselves and seek professional advice, because important protein-rich legumes are high in FODMAPs. It is therefore essential to select and combine foods specifically in order to compensate for potential nutrient deficiencies.

How do you evaluate the FODMAP concept in the context of general intestinal complaints or celiac disease (gluten intolerance)?

Regular or persistent intestinal complaints always require careful medical clarification, as an intolerance to milk sugar (lactose), fruit sugar (fructose), or gluten can present with similar symptoms. While celiac disease can be clearly diagnosed via an intestinal biopsy, a diagnosis for irritable bowel syndrome is made using clearly defined exclusion criteria. Although the FODMAP nutritional concept is low in gluten, it is not always gluten-free. Therefore, it is important that celiac disease and other potential conditions are ruled out when dealing with intestinal complaints before starting the FODMAP concept. If celiac disease is diagnosed, patients must follow a strictly gluten-free diet for life; even tiny traces of gluten must be avoided. In the case of lactose intolerance or fructose malabsorption, it is usually sufficient to avoid large quantities of foods containing lactose and fructose. That is an important distinction. The FODMAP concept is primarily recommended for irritable bowel syndrome.

You have written two FODMAP cookbooks: "Die FODMAP-Küche bei Reizdarm" and "Das FODMAP-Konzept – leichte Küche bei Reizdarm." Which points were particularly important to you in doing so?

With these books, I want to provide simple, practical guidance on how those affected by IBS can successfully implement the FODMAP concept in everyday life. On the one hand, it was important to me to explain the FODMAP nutritional concept in an easy-to-understand way, and on the other hand, the recipes needed to be straightforward and not require extensive cooking experience. With the abundance of different recipes, balanced and healthy dishes can be put together. Furthermore, it was essential to include useful tips—e.g., for using up leftovers or taking food on the go—as well as recipe variations, weekly plans, and frequently asked questions and answers. And, of course, the books contain helpful food tables based on the traffic light system so that readers can orient themselves more quickly and better plan their shopping and meals.

Common recipes often contain FODMAP-rich onions and garlic. Can you share how one can replace these ingredients?

FODMAPs are water-soluble but not fat-soluble. Therefore, you can manage well with homemade onion and garlic oil. Alternatively, you can sauté halved garlic cloves in a little oil in a pan and remove them completely before adding vegetables to the flavored oil. Another alternative is the green part of spring onions or scallions. These green stalks are low in FODMAPs, while the white part of the onion is not. Similarly, freshly chopped chives give recipes an onion-like flavor. Less known is garlic chives, also referred to as Chinese chives. This herb can be finely chopped and sprinkled in small portions over salads or dishes, providing a mild garlic flavor. You must be careful with (vegetable) stocks and seasoning mixes, as FODMAPs are often hidden in them. In the meantime, a few low-FODMAP stocks without onions and garlic have become available on the market.

Finally, what can you say about the gluten-free baked goods from Schnitzer GLUTENFREIHEIT with regard to the FODMAP concept?

First, one should realize that FODMAPs have nothing to do with gluten. FODMAPs are carbohydrates, and gluten is a protein, specifically the adhesive protein found in certain types of grain. For those suffering from IBS, the gluten-free baked goods from Schnitzer are very interesting because they use corn and rice. Monash University has classified these grains as having a significantly lower FODMAP content than wheat and rye. I think it's great that Schnitzer already offers over a dozen different products such as baguettes, panini, and sourdough bread that are certified by Monash University as low-FODMAP. As a health consultant for nutrition, I also pay attention to the content of nutrients and dietary fibers. The Schnitzer products also impress me here. I personally really like the gluten-free and low-FODMAP baguettes. And organic quality is close to my heart anyway, because sustainability and naturalness are important to me.

Thank you, Ms. Buhmann!