Nutritionists back calls for more fibre in our diets
University of Otago nutritionists say a major new British report that highlights the need for fibre in the human diet upholds their stance that the popular low-carbohydrate diets that are high in fat may not be ideal for our health.
A substantive report on the role of dietary carbohydrate on human health has just been published at the weekend by the Specialist Advisory Committee on Nutrition (SACN) to the British Government.
The report advises that people should consume at least 30g of fibre per day. It further recommends that carbohydrates should, on average, provide about half of daily calories, with as much of this as possible coming from "good" sources such as whole-grains and legumes.
This advice is compatible with research led by University of Otago nutrition expert, Professor Jim Mann, published in the world leading medical journals, Lancet, Lancet Diabetes and Endocrinology.
Dr Lisa Te Morenga, a Research Fellow from Otago's Edgar Diabetes and Obesity Research Centre, says the SACN recommendations are in direct conflict with recently popularised low-carbohydrate, high-fat (LCHF) diets.
"Although LCHF diets might be attractive in the short-term, the vast majority of people would find it impossible to achieve recommended fibre intakes on a LCHF diet in the long-term," she says.
Currently New Zealanders consume around 20g of dietary fibre per day, with breads and cereals being the major source. This is substantially less than the New Zealand and SACN recommendations that we eat 25-30g of dietary fibre per day. Those who avoid breads, cereals and legumes must therefore rely on very high intakes of fruit and vegetables to meet their fibre needs.
"Meeting the 30g dietary fibre goal by eating only fruit and vegetables as the source of fibre, seems unlikely for most of the population, given fruit and vegetable intakes are already quite low.
"Those who have elected to recommend LCHF diets should carefully consider this overwhelming endorsement of current dietary guidelines, which are based on extensive nutritional science. This guidance has played an important role in reducing the risk of coronary heart disease, and has the potential also to reduce the risk of obesity and its associated diseases, including some important cancers."
Other advice in the British report includes calls to radically restrict the intake of free sugars. Similar recommendations were made last year by the WHO, World Health Organization. This advice is based on the analysis of a huge body of scientific literature, including research undertaken at the University of Otago.
"The challenge now for governments worldwide, is to determine how best to achieve a target of less than 5% of total energy from free sugar. This advice is considered essential in the battle against some of the serious epidemic diseases of the 21st Century, notably type 2 diabetes and other diseases associated with overweight and obesity," says Dr Te Morenga.
