Effects of oligofructose-enriched inulin on intestinal absorption of calcium and magnesium and bone turnover markers in postmenopausal women

Br J Nutr. 2007 Feb;97(2):365-72. doi: 10.1017/S000711450733674X.


Deficiency of oestrogen at menopause decreases intestinal Ca absorption, contributing to a negative Ca balance and bone loss. Mg deficiency has also been associated with bone loss. The purpose of the present investigation was to test the hypothesis that treatment with a spray-dried mixture of chicory oligofructose and long-chain inulin (Synergy1; SYN1) would increase the absorption of both Ca and Mg and alter markers of bone turnover. Fifteen postmenopausal women (72.2 (SD 6.4) years) were treated with SYN1 or placebo for 6 weeks using a double-blind, placebo-controlled, cross-over design. Fractional Ca and Mg absorption were measured using dual-tracer stable isotopes before and after treatment. Bone turnover markers were measured at baseline, 3 and 6 weeks. Fractional absorption of Ca and Mg increased following SYN1 compared with placebo (P < 0.05). Bone resorption (by urinary deoxypyridinoline cross-links) was greater than baseline at 6 weeks of active treatment (P < 0.05). Bone formation (by serum osteocalcin) showed an upward trend at 3 weeks and an increase following 6 weeks of SYN1 (P < 0.05). Closer examination revealed a variation in response, with two-thirds of the subjects showing increased absorption with SYN1. Post hoc analyses demonstrated that positive responders had significantly lower lumbar spine bone mineral density than non-responders (dual X-ray absorptiometry 0.887 +/- 0.102 v. 1.104 +/- 0.121 g/cm2; P < 0.01), and changes in bone turnover markers occurred only in responders. These results suggest that 6 weeks of SYN1 can improve mineral absorption and impact markers of bone turnover in postmenopausal women. Further research is needed to determine why a greater response was found in women with lower initial spine bone mineral density.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Biomarkers / analysis
  • Bone Density / physiology
  • Bone and Bones / physiology*
  • Calcium / pharmacokinetics*
  • Cichorium intybus
  • Dietary Carbohydrates / administration & dosage
  • Dietary Supplements
  • Double-Blind Method
  • Female
  • Humans
  • Intestinal Absorption / drug effects*
  • Intestinal Absorption / physiology
  • Inulin / administration & dosage*
  • Magnesium / pharmacokinetics*
  • Oligosaccharides / administration & dosage*
  • Osteogenesis / physiology
  • Parathyroid Hormone / analysis
  • Postmenopause / physiology*
  • Vitamin D / analogs & derivatives
  • Vitamin D / analysis


  • Biomarkers
  • Dietary Carbohydrates
  • Oligosaccharides
  • Parathyroid Hormone
  • oligofructose
  • Vitamin D
  • Inulin
  • 25-hydroxyvitamin D
  • Magnesium
  • Calcium