Inulin modifies the bifidobacteria population, fecal lactate concentration, and fecal pH but does not influence iron absorption in women with low iron status
American Journal of Clinical Nutrition, 07/16/2012
Petry N et al. – Although inulin showed prebiotic activity, they were unable to show an increase in iron absorption in women with low iron status.Methods
- The subjects (n = 32) consumed inulin or placebo 3 times/d for 4 wk, separated by a 2-wk washout period.
- Iron absorption was measured after 3 wk of inulin and placebo consumption from a standard test meal by using stable-iron-isotope techniques.
- Fecal bacteria were measured by quantitative polymerase chain reaction and fecal acids by HPLC.
- Mean fractional iron absorption in the inulin (15.2%; 95% CI: 8.0%, 28.9%) and placebo (13.3%; 95% CI: 8.1%, 24.3%) periods did not differ significantly (P = 0.10).
- Inulin decreased fecal pH (P < 0.001) and increased fecal bifidobacteria (P < 0.001) and fecal lactate (P < 0.001) but had no effect on fecal SCFAs and total bacteria.
- Changes in lactate and acetate concentrations were positively correlated with changes in propionate (P < 0.001) and butyrate (P < 0.02) concentrations, respectively.
- Iron absorption correlated with fecal pH in the placebo period (P < 0.01) but not in the inulin period (P = 0.37).