Prebiotics – an added benefit of some fibre types

Abstract

Prebiotics are food components that are selectively used by gut bacteria, conferring a health benefit, most notably stimulating the growth of bifidobacteria. Accepted prebiotics at present are the fibre types galacto‐oligosaccharides, fructo‐oligosaccharides and inulin, some forms of which occur naturally in foods such as pulses, grains, fruit and vegetables. Prebiotics can also be isolated and produced commercially for use as functional ingredients and supplements. The aim of this paper is to provide an overview of the place of prebiotics in a healthy, balanced diet, to explore potential health effects, particularly in relation to gut health, and to consider whether there are implications of consuming a diet low in prebiotics. Dietary fibre is important for health, with high‐fibre diets reducing risk of several chronic diseases, via its effects on bowel function, gut microbiota, and cholesterol and glycaemic levels. The prebiotic effects of some fibre types may contribute to these effects. Evidence from supplementation studies carried out in humans suggests that consumption of prebiotics may confer an array of health benefits such as cholesterol lowering, relief of symptoms of gastrointestinal disorders, increased satiety and immunomodulatory effects, though more studies are needed. Findings from observational and intervention studies indicate that exclusion diets, such as low‐carbohydrate, gluten‐free and the low Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols diet, result in changes to the gut microbiota such as reduced abundance of Bifidobacterium and Lactobacillus species, though whether or not there are any long‐term health implications remains unknown. Studies investigating whether prebiotic supplements may be useful in conjunction with such diets (when these are required for medical reasons) to help restore levels of bacteria that are considered to be beneficial, are warranted. Overall, there is a need to promote high‐fibre foods across the UK population as intakes currently fall well below recommendations.

The role of bread in the UK diet: An update

“…Prebiotics, such as fructans [including fructo‐oligosaccharides (FOS) and inulin] and galactans (including galacto‐oligosaccharides, GOS), are defined as compounds that are selectively utilised by host microorganisms, conferring a health benefit (Gibson et al 2017). There is some evidence from randomised controlled trials that prebiotic supplements may improve fasting blood lipid concentrations (FOS and inulin), reduce travellers’ diarrhoea (longer chain ‘β’‐GOS) and reduce constipation (inulin), though more research is needed (Lockyer & Stanner 2019).…”

Reformulation of bread rolls using oat fibre: An acceptable way of dietary fibre enrichment?

“…Epidemiological evidence has consistently shown that a higher intake of dietary fibre is associated with a reduced risk of several chronic diseases including obesity, type 2 diabetes, cardiovascular diseases and various gastrointestinal disorders (Cho et al 2013; Kaur et al 2014; Velázquez‐López et al 2016). Fibre is a key nutrient for a healthy microbiome, acting as a substrate for fermentation by gut bacteria that produce thousands of enzymes for this purpose (Lockyer & Stanner 2019).…”

Nutrition: An old science in a new microbial light

“…Lockyer and Stanner () draw our attention to another group of plant‐based bioactives, prebiotics. Although traditionally categorised as a sub‐type of dietary fibre, the definition of prebiotics has been expanded by the International Scientific Association for Probiotics and Prebiotics (ISAPP) as ‘a substrate that is selectively utilised by host microorganisms conferring a health benefit’ (Gibson et al .…”

“…In the Virtual Issue 'The microbiome in nutrition and healthrole of probiotics and prebiotics' (2019), Igwe et al (2019) explore the effect of anthocyanins, a subclass of polyphenols, on the gut microbiota and their subsequent metabolites, some of which are considered more biologically active than intact anthocyanins. Lockyer and Stanner (2019) draw our attention to another group of plant-based bioactives, prebiotics. Although traditionally categorised as a sub-type of dietary fibre, the definition of prebiotics has been expanded by the International Scientific Association for Probiotics and Prebiotics (ISAPP) as 'a substrate that is selectively utilised by host microorganisms conferring a health benefit' (Gibson et al 2017).…”