A British Nutrition Foundation webinar finds promising therapeutic potential. But, we need a better understanding of what constitutes a healthy bug population and how diet can help maintain this long term.
Fibre’s health benefits, particularly when from cereals and wholegrains, are well documented. These include lower incidence of type 2 diabetes, cardiovascular disease and colorectal cancer.
Some types of fibre comprised of oligosaccharides – such as fructooligosaccharide and inulin – provide a fuel for bugs and are sometimes called prebiotics if they have been shown to confer health benefits.
But we still need to understand the number of bacterial species involved, and how they interact with each other and with us (the host). Research on whether polyphenols (bioactive substances in plants) may also have prebiotic effects is also underway.
Evidence for a beneficial role of resistant starch, another fibre type, is promising, but human health implications remain unclear. With wholegrains, fruit, vegetables and pulses, a key question is whether their effect is via fibre or through the bioactives they contain – or the result of an interaction between the two.
Potential health benefits
There has been interest for some time in the potential health benefits of probiotic bacteria, delivered via food or supplements.
But in order to carry a health claim, evidence to characterise the active strains within a diverse bacterial community in the product has to be provided – and delivering this has been the stumbling block so far.
Yet, substantial evidence exists for the beneficial effects of probiotics, especially in preventing antibiotic-associated diarrhoea and respiratory tract infections in at-risk children.
Judy Buttriss is director general of the British Nutrition Foundation