Friendly Bacteria and IBS

Friendly Bacteria and IBS
April is IBS Awareness Month, first held in 1997 and launched by the International Foundation for Functional Gastrointestinal Disorders (IFFGD). For further information about IBS Awareness Month, and for support and advice visit An estimated 9-23% of people worldwide suffer from irritable bowel syndrome (IBS), for which there is no known cure. Fortunately, there are ways to relieve symptoms of IBS, which include abdominal pain accompanied by diarrhea, constipation or episodes of both. One promising strategy for managing IBS involves the use of probiotics. These friendly bacteria live and work in the gut, where they are responsible for such things as:
  • Keeping pathogens (disease causing organisms) in check
  • Supporting normal immune function (and immune system development in children)
  • Synthesising nutrients such as vitamin B12
  • Modulating neurotransmitter levels.
How bacteria affect gut health Evidence from interventional trials and observational studies suggests that disturbances in the bacterial make-up of the gut, known as dysbiosis, may trigger or exacerbate IBS symptoms in some people. Anyone who has experienced gastrointestinal upset, or even an IBS flare, after taking antibiotics can appreciate how altering the microbiome in the gut can have unsettling consequences. Similarly, IBS may arise after food poisoning, gastroenteritis or other infection affecting the stomach or gut. Small intestinal bacterial overgrowth (SIBO) has also been associated with IBS, with antibiotics, somewhat ironically, often used to treat SIBO. Gut bacteria and inflammation Bacteria in the gut are also thought to be involved in the body's inflammatory response, which may offer an explanation as to why some people experience symptoms of IBS even when there's nothing to suggest it was caused by an infection. Changes in the bacterial population in the gut can modulate the production of inflammatory substances, and some people may have a genetic predisposition to an exaggerated inflammatory response. Some IBS sufferers also report more systemic symptoms such as fatigue and muscle aches and pains, even fibromyalgia. The idea that IBS involves abnormal levels of inflammation would go some way to explaining such symptoms, and offers a possible mechanism by which to manage such symptoms. The level of inflammation seen in IBS is a lot lower than that associated with inflammatory bowel diseases like ulcerative colitis and Crohn's disease. This does not, however, discount the suffering that people with IBS experience and the disruption the condition can cause in their everyday lives. Using probiotics in IBS The use of probiotic supplements, and eating a diet rich in prebiotic foods, can help some people with IBS to lessen symptoms. For others, certain foods may actually increase symptoms by increasing the production of gas as the bacteria in the gut digest this food. For the most part, the evidence from clinical trials suggests that one particular strain of friendly bacteria, Bifidobacterium infantis can help to relieve IBS symptoms such as abdominal pain and discomfort, difficulty with bowel movements, and distension or bloating. Other strains of Bifidobacteria and Lactobacillus have also been seen to modulate symptoms of IBS. As the gut provides a home for over 1000 kinds of bacteria, it is not all that surprising that some of the most significant benefits have been seen with the use of combinations of multiple strains of probiotics. Anyone considering using probiotic supplements to help with IBS management is recommended to discuss this first with their physician. It is also helpful to keep a log or diary of symptoms and other relevant information in order to see any patterns, and any benefits, emerging with the use of probiotics. References Hoveyda, N., Heneghan, C., Mahtani, K.R., Perera, R., Roberts, N., Glasziou, P. (2009). A systematic review and meta-analysis: probiotics in the treatment of irritable bowel syndrome. BMC Gastroenterol, Feb 16;9:15. Didari, T., Mozaffari, S., Nikfar, S., Abdollahi, M. (2015). Effectiveness of probiotics in irritable bowel syndrome: Updated systematic review with meta-analysis. World J Gastroenterol, Mar 14;21(10):3072-84.