Recent research at Korea University College of Medicine has indicated that a decrease in the diversity of bacteria in the intestine’s microbiome may be linked to the development of irritable bowel syndrome (IBS). The study combined a dataset of 576 IBS patients and 487 healthy 'control' patients to analyze the level of bacterial diversity, and results showed that the level of abundance of 21 specific bacterial species was lower in IBS patients than in healthy people, although the findings were not statistically significant.
The findings of this research are significant as they suggest a possible cause of IBS, however further research is needed in order to fully understand the impact of microbial diversity on IBS. It has previously been suggested that altered gut microbiota may be a possible cause of IBS and that acute bacterial gastroenteritis can cause chronic, asymptomatic, low-grade intestinal wall inflammation, which can alter neuromuscular and epithelial cell function.
The research indicates that there may be a correlation between the gut microbiota and IBS, although further research is necessary to prove a causal relationship. In the meantime, the US National Library of Medicine has more information on IBS and its symptoms.