The health benefits of insoluble dietary fibre from plant sources have long been lauded – but bioactives found in these fibre-rich foods give yet another reason to prioritise their inclusion in diets, say scientists.
Desirable bioactives – including quercetin, resveratrol, catechins, anthocyanins, lutein, lycopene, and beta-carotene – were found in a variety of plant foods that also contain insoluble dietary fibre, offering potential benefits beyond those of the fibre itself, according to researchers from the University of Minnesota and biotech company Brightseed.
The discovery offers an opportunity to fortify processed foods, they suggest. Byproducts of food production, such as peel, hulls, pulp, and pomace, are generally high in fibre and bioactives, and as such can offer nutritional value from sustainable sources.
“The suggestion to eat more fruits and vegetables isn’t a novel idea, but it’s something most people still struggle to do,” said Jan-Willem van Klinken, co-author of the study and senior vice-president of medical, scientific, and regulatory affairs for Brightseed.
“If we can offer widely accessible fibre-fortified products that have been developed to enhance rather than negate bioactive content, we can provide consumers with increased nutritional value.”
The study, which was published in Nutrients, aggregated the available literature on the health benefits of bioactives – compounds that have been linked to lower incidence of cardiovascular disease, cancer, and type 2 diabetes – in plant sources of insoluble dietary fibre.
It found that a variety of plant foods, including fruits, vegetables, legumes, nuts, seeds, and whole grains, contained insoluble dietary fibre; what’s more, each source contained different bioactives that support health in various ways.
“People understand the need for fibre and how it relates to gut health – an area of wellness that is becoming increasingly important as scientific research continues to reveal its impact on overall health and wellbeing,” said Joanne Slavin, co-author of the paper and a professor in the university’s College of Food, Agricultural, and Natural Resource Sciences.
“Fibre is the marker of health that is included in our dietary guidelines and found on product labels, but our research indicates that we need to ensure the other valuable components of fibre-containing plant sources – the bioactives – are also recognised as providing valuable benefits for human health.”
Plant sources with bioactives and insoluble dietary fibre could be used in food fortification, the researchers suggest.
These findings illuminate the need for industry, academia, and governments to join forces to champion awareness and education about how bioactives can be exploited in food and health systems, according to the team behind the research.
“The collection of literature we reviewed and the results of this research can serve as a paradigm shift in how the food and health industries, as well as consumers, view insoluble dietary fibre and bioactives,” said lead author Madeline Timm, who co-authored the research for her graduate project at the University of Minnesota. “Continued research and broad inclusion of bioactives in foods and supplements can have a real impact on human health.”
Further research is also needed to identify extraction and processing methods that preserve and optimise bioactive compounds.
