Novel barley boosts bowel health in humans: study
for formulators to double the fibre content of products, and boost
gut health in consumers, suggests new research.
A human trial using food with Himalaya 292, a novel hull-less barley, increased levels of short chain fatty acids (SCFA) by 57 per cent in a randomized, cross-over trial performed by scientists at Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO).
The pH of faeces also decreased, while excretion of butyrate - a SCFA that has been found to be a major factor contributing to healthy colon mucosa - increased by 91 per cent, report researcher in the British Journal of Nutrition .
"Consumption of a diet that included foods made from Himalaya 292 supplied more fibre and improved indices of bowel health compared with refined cereal foods and, for some indices, similar wholemeal wheat foods at equivalent levels of intake," wrote lead author Tony Bird.
Most starches are digested and absorbed into the body through the small intestine, but some resist digestion and pass through to the large intestine where they act like dietary fibre and improve digestive health.
This type of starch is called resistant starch.
And tapping into opportunities gleaned from the growing trend for health and wellness foods, resistant starches fit squarely into the low-glycaemic food trends, as well as health product positions such as prebiotic fibre benefits and a healthy digestive system.
The researchers recruited 17 volunteers aged between 31 and 66 and randomly assigned them to consumed food formulated with similar quantities of Himalaya 292 (Hordeum vulgare var.
Himalaya 292), whole-wheat or refined cereal foods daily for four weeks.
Daily fibre intakes were calculated to be 45, 32 and 21 grams for the Himalaya 292, whole-wheat and refined cereal periods, respectively, said the researchers.
This increase in fibre intake during the Himalaya 292 period was associated with a 33 per cent increase in faecal weight, while the pH of the faecal matter decreased from 7.24 to 6.98 after consuming the novel barley-formulated foods.
Building on previous science Promising results have previously been reported from animal studies.
The researchers reported in 2004 in the Journal of Nutrition similar reductions in faecal pH, and increased excretion of SCFAs in the faeces.
Playing with the genes The novel, hull-less barley cultivar is obtained following a change in a single nucleotide in the gene encoding starch synthase IIa.
Such a change is reported to inhibit enzyme activity, producing a grain with higher levels of amylose, and lower levels of starch.
Source: British Journal of Nutrition May 2008, Volume 99, Issue 05, pp 1032-1040, doi: 10.1017/S000711450783902X "Wholegrain foods made from a novel high-amylose barley variety (Himalaya 292) improve indices of bowel health in human subjects" Authors: A.R. Bird, M.S. Vuaran, R.A. King, M. Noakes, J. Keogh, M.K. Morell, D.L. Topping
