Bacillus clausii and Irritable Bowel Syndrome (IBS): Scientific Evidence

Bacillus clausii is a spore-forming probiotic bacterium that has been studied for its potential to support intestinal health, including in individuals with Irritable Bowel Syndrome (IBS). The rationale for its use is based on observations that IBS is often associated with alterations in gut microbiota and immune function. B. clausii is believed to help restore microbial balance, enhance barrier function, and modulate immune responses in the gut.

Several small randomized controlled trials and open-label studies have evaluated the effects of B. clausii in IBS patients. Some studies have reported improvements in global IBS symptoms, abdominal pain, bloating, and stool consistency compared to placebo. For example, a 2017 randomized trial found that a multi-strain probiotic containing B. clausii led to modest but significant symptom relief in IBS patients. However, the number of high-quality, large-scale studies specifically targeting B. clausii in IBS is limited, and results are not always consistent.

Overall, while there is preliminary scientific evidence suggesting that B. clausii may benefit some IBS patients, the strength of the evidence is moderate at best, with most studies being small and sometimes lacking rigorous controls. Thus, B. clausii's use in IBS is scientifically plausible and supported by some research, but further robust, large-scale clinical trials are needed to confirm its efficacy and establish optimal usage guidelines.