Fibre: The Next Essential Nutrient? Otago Researchers Make Case

For the first time in 50 years, a new item, fibre, could be added to the list of essential nutrients needed to keep humans healthy — if University of Otago researchers get their way. It was recently added by Otago nutrition researchers, who believe it has the ability to "appreciably reduce" the disease burdens associated with diabetes, heart disease and colorectal cancer. Research co-author Associate Prof Andrew Reynolds said vitamins A, B, C, D and E, minerals such as iron and copper and some of the building blocks of fats and proteins had long been recognised as essential. But never a carbohydrate, and now he and fellow researchers are calling for dietary fibre to be officially recognised internationally as an essential nutrient. Co-author Prof Sir Jim Mann said to be recognised as essential, the nutrient had to be beneficial to human health, to not be produced by the body itself and absence of the nutrient to result in a measurable deficiency state. To date, it had been the lack of a deficiency state that had prevented fibre from being recognised as essential. He said proof that fibre was essential lay in the gut microbiome. "In some ways, it’s quite simple: the gut microbiome exists almost exclusively on the dietary fibre we eat. "A healthy gut microbiome is linked to all sorts of health benefits, with more discovered and understood each day." Their argument is supported by more than 100 years of research into fibre’s chemistry, physical properties, physiology and metabolic effects, as well as more recent meta-analyses and clinical trials — many of which were conducted at Otago. Assoc Prof Reynolds said the research team examined if there were any causal associations between dietary fibre intake and health outcomes, and found overwhelming evidence of benefit. "Looking across multiple studies, we see that when people increase fibre intakes, their body weight, cholesterol, blood sugars and blood pressure all improve. "When following people over decades, we see those with higher fibre intakes get less heart disease, less type-2 diabetes, less colorectal cancer and are less likely to die prematurely." He said if people increased their intakes of high-fibre foods such as whole grains, legumes, vegetables and whole fruit, it was likely to deliver substantial health benefits. "The more that fibre is recognised and prioritised, the better. "The disease burden associated with diabetes, heart disease and colorectal cancer would be expected to be appreciably reduced by such a dietary change." At present, New Zealanders eat an average of 20g of fibre a day, but the World Health Organisation guideline recommended at least 25g per day. Sir Jim said recognising dietary fibre as an essential nutrient would help to ensure that dietary guidelines, nutrition education programmes and health professionals provided greater emphasis on adequate intakes of fibre, with reformulation of food products and changes in food labelling likely to follow. "Increased intakes of fibre, which would be expected with greater awareness, have the potential to appreciably reduce the huge burden of non-communicable diseases facing Aotearoa New Zealand."