Calcium and Magnesium Absorption from the Colon and Rectum Are Increased in Rats Fed Fructooligosaccharides

Abstract

We investigated the effects of fructooligosaccharides on the absorption of calcium, magnesium and water from the colon and rectum of rats fed a control diet or the control diet containing 50 g fructooligosaccharides/kg. Chromium-mordanted cellulose was used as an unabsorbable marker to calculate apparent absorption of calcium and magnesium. There was a positive correlation (r = 0.982, P < 0.001 in rats fed the control diet and r = 0.975, P < 0.001 in rats fed the fructooligosaccharides-containing diet) between the amount of chromium and the dry weight of each fecal pellet in the colon and rectum. Ratios of calcium to chromium and magnesium to chromium in fecal pellets in the colon and rectum were calibrated from the Ca:Cr and Mg:Cr ratios of cecal contents. In rats fed the fructooligosaccharides-containing diet, but not in rats fed the control diet, these ratios were correlated with the fractional length of transit along the colon and rectum, indicating linear disappearance of calcium and magnesium during the colorectal passage. Total apparent absorption of calcium and magnesium, predicted from regression equations with the Ca:Cr and Mg:Cr ratios of cecal contents, agreed well with those calculated from the Ca:Cr and Mg:Cr ratios of feces. The consumption of fructooligosaccharides did not affect net water absorption from the colon and rectum. These results indicated that fructooligosaccharides significantly increased calcium and magnesium absorption and that indigestible and fermentable carbohydrate facilitates colorectal absorption of calcium and magnesium.

Effect of soluble or partly soluble dietary fibres supplementation on absorption and balance of calcium, magnesium, iron and zinc in healthy young men

“…This is the ®rst time, to our knowledge, that such an effect has been observed in humans. These results con®rm previously reported data from animal investigations in our own laboratory, (Demigne  et al, 1989;Levrat et al, 1991;Younes et al, 1996), and by other workers (Delzenne et al, 1995;Ohta et al, 1995). Several hypothesis about the mechanisms of the effect of inulin on Ca absorption could be proposed.…”

“…In our laboratory, we showed that inulin enhanced Ca and Mg absorption in animal studies (Demigne  et al, 1989;Levrat et al, 1991). This observation was recently con®rmed by other workers also in animal studies (Delzenne et al, 1995;Ohta et al, 1995). Unfortunately, limited information is available for humans, and only indirect evidence that this effect could occur in humans has been reported (Trinidad et al, 1993(Trinidad et al, , 1996.…”

Ingestion of polydextrose increase the iron absorption in rats submitted to partial gastrectomy

“…The final concentration of hematocrit (eight weeks) in the rats with gastrectomy was not different from the sham-operated rats fed with any one of the diets (Figure 1). Similar effects have also shown by other researchers for other prebiotics [19][20][21][22] .…”

“…In this respect, it is important to point out that there is a substantial positive correlation between the concentration of serum iron and the absorption of iron. Studies with fructooligosaccharides also presented an increased absorption of iron in deficient rats iron deficiency 19 , suggesting that this diet could prevent the anemia.…”

Breadmaking performance and technological characteristic of gluten-free bread with inulin supplemented with calcium salts

“…As an effect of fermentation, the reduction in pH occurs as the result of stimulated production of lactic acid and short-chain fatty acids, mainly propionate, acetate and butyrate [30]. At lower pH, more mineral is soluble in the gut lumen and thus is more readily absorbed from the gut mucosa cell [31]. Apart from indirect stimulation of minerals absorption by increasing its solubility via lowering the pH, short-chain fatty acids can also directly influence its bioavailability by complexing with the minerals leading to an increase in their absorption.…”