We are looking forward to an interesting conversation in which both dialogue partners move from different directions towards a common goal: the promotion of our gut health for optimal well-being! 

Daniel Kövary is the founder of the Munich-based "toilet stool start-up" stuul. Dr. med. univ. Nikolaus Gasche is the co-founder and -managing director of the now better described as Grown-up company myBioma from Vienna, the leading provider of self-tests for the composition of the intestinal microbiome in German-speaking countries.

We all know that a healthy gut is crucial for our well-being. But how can we optimally support this crucial factor? Stuul and myBioma have very different approaches to this, but they complement each other perfectly. While one focuses on the correct posture when going to the toilet in order to optimize the elimination processes, the other offers the possibility to explore and specifically support the individual microbiome.

So which of you would like to get started?


Thank you very much! I will gladly take over. I also find the constellation very exciting. We at stuul see the intestine more as a tube that should be stretched to facilitate bowel movements, while you at myBioma are mainly concerned with the contents of this tube. A holistic view of the rectum.  

But perhaps first briefly about me and my "big business" with the toilet stools. I founded Stuul 4 years ago because my wife forbade me to put a conventional toilet stool in our bathroom. She thought this loveless white plastic bowl was just too unaesthetic for our bathroom. Above all, she would have been embarrassed in front of our guests. For them, the sight of the toilet stool would immediately start the head cinema and they would imagine in all details, from which intimate diseases we would suffer.  That was at least her fear and so the toilet stool was banned again from our bathroom on the very first day.

But since I was still convinced of the health-promoting effect of the natural squatting posture during bowel movements, I made it my business to completely reinvent the toilet stool. The result of a very long and exciting development process is our stuul.

And Nikolaus, how did you end up in the "bowel business"?


Thank you very much, it is a pleasure to be here. The founding of myBioma together with my co-founder Barbara Sladek stems from a combination of my medical passion, her scientific expertise and our shared desire to improve people's gut health.


Throughout my training and work as a medical doctor, I've always found how critical the microbiome is to our health. It is fascinating to realize that our gut is colonized by trillions of bacteria that perform an impressive variety of functions. These microorganisms affect not only our digestion, but also our immune system, mood, energy metabolism, and many other aspects of our health.

As I delved deeper into the research on the microbiome, I realized that understanding and harnessing this knowledge offers tremendous potential for the prevention and treatment of a wide variety of diseases. From gastrointestinal disorders to metabolic disorders to mental illness, the microbiome plays a critical role.

And this is where myBioma comes in. We offer advanced analytical methods to examine the individual microbiome and provide recommendations on how to optimize gut health.

So how does your stuul work compared to traditional plastic bowls?

Toilet Stool stuul Ocean


So from a pure health perspective, all the toilet stools out there should have about the same benefits. But strictly speaking, so does a stack of books or an upturned laundry basket. The point of a toilet stool is, after all, to allow you to assume a kind of squatting position when you defecate. In this natural position, the rectum is stretched and the actual emptying of the bowels can take place more quickly and, above all, more completely. There is no need to press and squeeze, which is partly responsible for many typical diseases of civilization such as hemorrhoids or constipation. 

In terms of sustainability and design, however, we stand out even more clearly from the competition. In terms of design, it was important to us to break the chains of association described above, which my wife feared would occur among guests. We succeeded in doing this by completely breaking up the shape of the stool by dividing the design into two parts. The guests now only see a kind of box in the host's bathroom and wonder at most what function this box might have. 

Now, I also didn't want to release just another plastic piece into the world, so we focused on sustainability from the very beginning of product development.

For one thing, we didn't want to produce in faraway countries. For me, it is out of the question to base our business model on exploiting global social disparities and low environmental standards in other countries. That's why we opted for climate-neutral production in Germany. 

Secondly, the material we have chosen also has very good properties from an ecological point of view. It consists of more than 90 percent air, which alone saves material. But it can also be 100 percent recycled. That is very rarely the case with plastics. So we can easily make a new stuul out of any returned stuul that can no longer be used.

But back to our common topic, the gut. Can you tell me about the importance of the microbiome for bowel movements? Is there perhaps any scientific research on this yet?


Your sustainable approach is very impressive! Regarding the microbiome and its importance for bowel movements, there is indeed extensive scientific research.

One interesting study, published in the journal 'Gut' (https://pubmed.ncbi.nlm.nih.gov/26069274), looked at the link between the gut microbiome and stool consistency, as measured by the Bristol Stool Scale (BSS). The BSS reflects stool water content and activity and serves as a measure of intestinal colonic transit time.

In this study, 53 healthy women were examined, and a strong correlation was found between stool consistency and various microbiome indexes. For example, more liquid stool texture was negatively associated with species diversity and positively associated with the ratio of Bacteroidetes to Firmicutes. In addition, certain microorganisms such as Akkermansia and Methanobrevibacter were associated with firmer stool texture. The researchers suggested that the different stool textures may be related to individual transit times and that accelerated transit times would contribute to differentiation of the colonic ecosystem.

Could you tell us more about the health benefits of natural squatting during bowel movements? How does your squat affect bowel movements?

stuul toilet stool pink


I myself am not a doctor and therefore not an expert. But of course, I have talked to many proctologists over the years about the benefits of using toilet stools during bowel movements. Most proctologists I've talked to recommend, among other things, that their patients use a toilet stool when they have problems with bowel movements. 

The reason for this is the so-called puborectal muscle, which forms a kind of loop around the rectum and bends the rectum like a garden hose. For us, this is a very practical, passive safety mechanism that ensures that we do not unintentionally empty ourselves when walking or standing, or that we do not have to constantly tense the external sphincter muscle. 

However, when we normally sit on the toilet, the puborectal muscle remains tense and makes emptying difficult because the bowel is still somewhat kinked. We have to push and squeeze to move the stool past this kink in this position. In this way, constipation can become entrenched, but also diseases such as hemorrhoids can be promoted by the high internal pressure on the intestinal mucosa. Only when squatting does the puborectal muscle relax and the rectum is stretched like a downpipe. In this position, the stool can be emptied faster, more effortlessly and also more completely.

I know from my own experience that there must be something to it. It's simply much more pleasant to do your business while squatting. In any case, I wouldn't want to do without my toilet stool and now take it with me on vacation.

You say that the transit time of the stool is determined by the composition of the microbiome, but also has a reverse influence on the composition of the microbiome. Does that mean that if you have liquid stool according to the Bristol Stool Scale, for example, you could take psyllium husks to solidify the stool and the resulting increased transit time could in turn lead to a positive change in the microbiome? Or conversely, using a toilet stool for constipation could result in a faster transit time and thus stimulate a beneficial change in the microbiome?


Puborectal muscle relaxation undoubtedly plays an essential role in facilitating defecation, based on established biomechanical principles. 

Diet has a central role in controlling stool consistency and digestive health. In this context, dietary fiber, such as that found in psyllium husks, is of particular interest. A remarkable aspect of psyllium husks is that they can be used for two opposing intestinal conditions: diarrhea and constipation. In this case, the dosage and method of application is crucial.

Furthermore, psyllium husks act as prebiotic food for the intestinal microbiota. The ingestion of psyllium husks leads to a selective stimulation of butyrate-producing bacteria. These microorganisms are responsible for the production of butyrate, a short-chain fatty acid that has anti-inflammatory properties and is instrumental in maintaining intestinal health. Targeting the intestinal microbiota through the consumption of psyllium husks may thus have a positive impact on inflammatory regulation in the gut and contribute to the overall promotion of well-being. 

A toilet stool could actually influence the transit time of bowel contents, as this squatting position relaxes the puborectal muscle, which may result in smoother passage of stool. However, I'm sure you can say more on this topic.  What is the study evidence here regarding toilet squatting?

Toilet Stool stuul Charcoal


In fact, there are already numerous studies* on the subject of posture and bowel movements, the vast majority of which have found a significant improvement in bowel movements by adopting a squatting position. 

One study, on the other hand, sees no correlation between sitting posture during bowel movements and the likelihood of developing colorectal cancer, and another is unable to demonstrate this correlation in the case of constipation. I think the problem is that the number of participants in the studies was simply still too small to provide firm evidence, but that is often lacking in medicine.

But that doesn't mean that we don't attach great importance to the scientific aspects. We are in regular exchange with a number of very renowned proctologists who, as mentioned earlier, very often recommend the use of a toilet stool to their patients. One of them is Daniel Sterzing, MD. He is a surgeon, visceral surgeon and proctologist and works at the Proctological Center Berlin. Mr.. Dr. Sterzing advises, for example, all those who have to press during defecation or have the feeling of incomplete emptying to use a toilet stool.

Science is at the center of you and your product, so to speak. Your microbiome analysis examines all the bacteria in the stool and then provides your customers with a comprehensive report on the types and composition of their individual microbiome. I can think of so many different user groups for whom such an analysis could be extremely valuable, from people with various intestinal diseases to people with obesity to people with mental disorders or brain disorders. Really fascinating!

Somehow, I have a feeling that this is just the beginning. The privacy-compliant research data on the population's microbiome obtained in this way could lead to real leaps in knowledge in the field, especially if the whole thing is perhaps analyzed using artificial intelligence. But other services, such as providing customized stool samples for stool transplants at home, are also quite conceivable. 

Finally, can you perhaps tell us in which direction you are thinking and where the journey of myBioma could still go?


I believe that our journey leads to an extremely promising future of medical research. At myBioma, we are determined to be at the forefront of this exciting development. As active participants in numerous studies, I am proud to say that we are already strongly committed and intend to maintain this pioneering path in the future.

Our pioneering diagnostic tools built on the microbiome are helping to deepen our understanding of disease and further advance personalized approaches to medical treatments. Therefore, we will continue to pursue this path.

One example of our diagnostic tools is BiomeOne. I am convinced that this innovative method can identify patients with tumor diseases more accurately than conventional laboratory tests and that they will respond positively to the latest immunotherapies (immune checkpoint blockade).

And what about you?


For us, the topic of internationalization will be on the agenda for next year. Last year, we concentrated fully on the German-speaking region and have now managed to build up a certain brand awareness in that market and capture a significant market share. Our goal was to build up real expertise in marketing toilet stools in our home market. The focus has always been on the Amazon channel, our own web store and working with other online platforms as distribution partners. 

I think we can now use this knowledge in other countries to develop these markets efficiently. In addition to neighboring European countries, the focus is primarily on the U.S. market. This is because toilet stools are very popular in the US. The inventor of the toilet stool Squatty Potty has managed to completely de-taboo the toilet stool there and today it is almost regarded as a national cultural asset by Americans. This was certainly helped by their viral commercial, which everyone should take a look at on YouTube if they want to have a real laugh.

I would like to thank you very much for the very interesting exchange with you and wish you all the best and much success for your future plans. We should definitely talk again in a few years to see if and how the plans have come to fruition.


That sounds really exciting! I am sure you will achieve great things in this area.

Thank you so much for that, I really enjoyed talking with you. I wish you much success as well and look forward to our further exchanges.


(click on the image below to get to the myBioma Website)



*Studies on the health benefits of squatting when having a bowel movement, including the use of toilet stools::

  • Sikirov, D. - Comparison of Straining During Defecation in Three Positions. Results and Implications for Human Health, Digestive Diseases and Sciences, Juli 2003
  • Sohrabi et al.: Squatting and risk of colorectal cancer:a case-control study (Middle East Journal of Digestive Diseases, 2012)
  • Sakakibara, Ryuji et. al - Influence of Body Position on Defecation in Humans
  • Bhattacharya Sudip et al. - Health promotion and prevention of bowel disorders through toilet designs: A myth or reality? Journal of Education and Health Promotion, Februar 2019
  • Trieu et al.: Using a footstool does not aid simulated defecation in undifferentiated constipation: A randomized trial (Gastroenterology, 2022)
  • Dr. B.A. Sikirov - Etiology and pathogenesis of diverticulosis coli: a new approach, Medical Hypotheses, 26. Mai 1988
  • Bockus, H.L. - Gastroenterology, (Philadelphia: W.B. Saunders Co., 1944), Vol. 2, Page 469
  • Ghoshal UC et al. - Indian consensus on chronic constipation in adults: A joint position statement of the Indian Motility and Functional Diseases Association and the Indian Society of Gastroenterology. Indian Journal of Gastroenterology: Official Journal of the Indian Society of Gastroenterology, 2018
  • Saeed Rad- Impact of Ethnic Habits on Defecographic Measurements. Arch Iranian Med, 2002
  • Chuah KH, Mahadeva S. - Cultural Factors Influencing Functional Gastrointestinal Disorders in the East. Journal of Neurogastroenterology and Motility, Oktober 2018
  • Dimmer, Christine, Brian Martin et al. - Squatting for the Prevention of Hemorrhoids, Department of Science and Technology Studies, University of Wollongong, NSW 2522, Australia, Townsend Letter for Doctors & Patients, Nr. 159, October 1996
  • Dr. B.A. Sikirov - Management of Hemorrhoids: A New Approach, Israel Journal of Medical Sciences“, 1987
  • Sakakibara, Ryuji et. al - Influence of Body Position on Defecation in Humans“ LUTS 2010, 2:16-21
  • Modi, Rohan M. et al. - Implementation of a Defecation Posture Modification Device. Impact on Bowel Movement Patterns in Healthy Subjects. Journal of Clinical Gastroenterology, March 2019