Role of Probiotics and Prebiotics in Irritable Bowel Syndrome

Irritable bowel syndrome (IBS)

Irritable bowel syndrome (IBS) is a common, chronic gastrointestinal (GI) condition characterized by disturbances in bowel habits and abdominal pain in the absence of known organic pathology. IBS reduces the quality of life and is costly to treat.

IBS symptoms

1. abdominal pain
2. bowel dysfunction which includes constipation, diarrhoea, or alternating periods of both

Probiotics

According to FAO/WHO probiotics are: “Live microorganisms which when administered in adequate amounts confer a health benefit on the host”. Lactic acid bacteria and bifidobacteria are the most common types of microbes used as probiotics but certain yeasts and bacilli may also be helpful.

Prebiotics

Prebiotics are non-digestible food ingredients that stimulate the growth and/or activity of bacteria in the digestive system in ways claimed to be beneficial to health. Typically, prebiotics are carbohydrates (such as oligosaccharides), but the definition may include non-carbohydrates.

“A prebiotic is a selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microflora that confers benefits upon host well-being and health”.

IBS and its relationship with pro and prebiotics

IBS is a gastrointestinal tract dysfunction with a complicated etiology. The human gastrointestinal system harbors a complex community of micro-organisms generally bacteria whose relationship with the host is normally mutually advantageous. IBS is a condition in which this relationship is disturbed.

Can probiotics and prebiotics help?

Research has shown evidence that prebiotics and probiotics have the ability to correct IBS to a certain extent.

Probiotics have been seen to enhance gut barrier function, inhibit pathogen binding and reduce gut inflammation (3). Probiotics reduce pain and symptom severity scores. The results of another study showed the beneficial effects of probiotics in IBS patients in comparison with placebo (4). Probiotics exhibited the potential to reduce pain and symptom severity.

Features of probiotics possibly relevant to the treatment of IBS 

1. Probiotic bacteria adhere to mucosa and inhibit the adherence of pathogenic bacteria.
2. Increase the barrier function of the gut lining
3. Secrete bacteriocins (Bacteriocins are proteinaceous or peptidic toxins produced by bacteria to inhibit the growth of similar or closely related bacterial strain).
4. Probiotics acidify colon by nutrient fermentation which may inhibit certain unwanted bacteria
5. Immunomodulatory action
6. Modification in mucosal response to stress
7. Probiotics are anti-inflammatory. Inflammation causes visceral hypersensitivity.

A number of studies have shown that changes in the diet can alter colonic fermentation patterns. Prebiotics has a valuable property of modifying individual strains and species of the gut community of microbiota.

The use of probiotics, prebiotics, symbiotics and dietary manipulation of gut microbiota to treat IBS is becoming common. Though insufficient knowledge about types, formulations, indications, and doses are currently available, this is a promising method to deal with IBS.

Each probiotic has exclusive characteristics and IBS patients are diverse with different or overlapping symptoms.  A word of caution by scientists is that probiotics and prebiotics should not be indiscriminately used.