A Randomized Controlled Clinical Trial to Investigate the Efficacy of Lacto-fermented Sauerkraut and the Probiotic E. Coli Nissle 1917 in the Treatment of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a chronic gastrointestinal (GI) disorder that affects around 11% of the population globally. Several factors have been implicated in the pathogenesis of IBS, including psychological stress, gastrointestinal motility, and diet. More recently, it has become clear that the gastrointestinal microbiota may play a critical role in the pathophysiology of this functional GI condition.

Gut microbiome manipulation, for example through the use of probiotic and prebiotic supplements, has shown some promise in the treatment of IBS. However, the research in this area is still in its infancy, and it remains unclear what type of intervention that is the preferred choice in cases of IBS. Many, if not most, probiotic supplements on the market today contain bacteria that are incapable of colonizing the human gut, which may partly explain why the health effects associated with the use of probiotics tend to be temporary, rather than permanent.

Several studies have investigated how the use of probiotic supplements containing Bifidobacteria and Lactobacilli affect the clinical outcome of patients with IBS. However, to date, no studies have assessed whether fermented vegetables, a "natural" source of probiotic bacteria, are useful in the treatment of IBS. Moreover, little is known about how other types of probiotic bacteria, such as those belonging to the genus Escherichia, affect symptoms of IBS.