Effect of dietary fibre mixture on growth and intestinal iron absorption in rats recovering from iron-deficiency anaemia

Abstract

There is concern regarding the possible negative effects of ingestion of dietary fibre on growth and intestinal Fe absorption in infants. The aim of the present study was to compare the effect of a fibre mixture on the growth and the intestinal absorption of Fe in rats with Fe-deficiency anaemia with that of a diet without fibres. Faecal weight and caecal pH were also evaluated. According to the Hb depletion–repletion model, twenty-two male weaned Wistar rats were fed the AIN93-G diet without Fe until Fe-deficiency anaemia was induced with Hb < 70 g/l. The anaemic rats were divided into two groups: (1) fibre mixture group – fed 100 g of fibre mixture/kg of diet (soya polysaccharide, inulin, resistant starch, Arabic gum, fructo-oligossaccharide and cellulose) (n 11); (2) control group – fed without fibres (n 11). All diets had 157 mg of ferric citrate (30 mg of elemental Fe) added to lead to recovery from anaemia. Fe intestinal absorption was measured by Hb repletion efficiency (HRE) and apparent Fe intestinal absorption. The HRE was 44·8 (sd 9·5) % in the fibre mixture group and 43·0 (sd 9·5) % in the control group (P = 0·664). The apparent Fe absorption was 46·2 (sd 16·5) and 47·2 (sd 10·2) % (P = 0·861) in the fibre mixture and control groups, respectively. The faecal weight median was 6·17 g in the fibre mixture group and 2·11 g in the control group (P < 0·001). The caecal pH was in the same order: 6·11 (sd 0·59) and 7·07 (sd 0·34) (P < 0·001). Both the groups consumed similar quantities of diet, and growth was similar in both the groups. The fibre mixture had no influence either on growth or on Fe intestinal absorption in rats recovering from anaemia. This mixture favoured an increase in faecal weight and a decrease in caecal pH.