Irritable Bowel Syndrome (IBS) is a common, relapsing condition. Its cause is not completely understood. But its occurrence increases following gut infections, such as food poisoning or gastroenteritis. These conditions can cause changes in the gut microbiota. This article discusses the idea that the benefits of probiotics help to ease the symptoms of IBS?

The main symptoms of IBS are abdominal discomfort or pain with an alteration in bowel habit. This alteration may be constipation, diarrhoea, or alternating between constipation and diarrhoea. The condition impacts heavily on quality of life. And sufferers may not seek help due to uncomfortable and invasive test procedures. Leading to long-term IBS, often accompanied by anxiety or depression and feelings of helplessness.

Though it is not known exactly why some people develop IBS there are several theories. As we know that IBS often develops following a gut infection. One theory suggests that an imbalanced gut bacteria population could be to blame. Though there are likely other additional factors that contribute to IBS. Would probiotic supplementation help?

Our personal microbiota outnumber our own cells by 10 to 1. They have a critical role in our health. We provide them with a home and they in return perform vital functions for us. They maintain the health of the cells lining the gut. They provide protection against invading pathogenic bacterial species. They help to regulate our immune system and produce vitamins for us.

We know that the microbiota is different in people with IBS, compared to people without it. Studies also show that there are different IBS types with specific changes to the microbiota. Such as IBS that is associated with diarrhoea (IBS-D). And IBS associated with constipation (IBS-C). And we now know that symptoms of IBS change with the use of antibiotics, probiotics and prebiotics. Perhaps due to their influence on the gut microbiome.

We are still learning about all the benefits of probiotics. Studies are limited and much of the research has been carried out on animals rather than people. However, we do know that probiotics can limit the colonisation of the gut by pathogenic bacteria. They make the gut environment less favourable to the growth of certain micro-organisms. And, they change the behaviour of the existing microbiota. Influencing stool consistency by changing bile salt conjugation.

We also know that not all probiotics are helpful in every case. A careful choice is needed based on the predominant symptoms. Supplementing certain Bifidobacterium species, such as B. infantis, B. brevis and B. animalis consistently leads to improvements in the symptoms of bloating and constipation. Whilst the Lactobacillus species, L. plantarum, L. casei, L. reuteri, L. acidophilus, and L. rhamnosus improve the symptoms of abdominal pain, bloating, diarrhoea and constipation. Other factors to consider are the dosage of the probiotic product. And how many viable colony forming units it contains.

Other approaches such as changes in diet can be helpful adjuncts to therapy. Restricting certain types of carbohydrates, known as FODMAPs can be useful. This may only address the symptoms rather than the cause. But after years of suffering, any symptom reduction can be immensely helpful.