Dr. Ohta's research with rats suggests that in humans each 1 gram per day of fructooligosaccharides (FOS) may increase Mg uptake by 2-3 mg/day. Human research of FOS has not been done yet.
FOS is a sweetener commonly used in Japan. The suitable level of FOS intake is 3-7 grams per day. Maximum FOS intake per day should not exceed 18-20 grams for males. (The suggested intake for males is 0.3 g per kg body weight, for females: 0.4 g per kg.)
Below are abstracts of seven papers which discuss fructooligosaccharides and the absorption of magnesium.
Atsutane OHTA, Naomi OSAKABE, Kazuhiko YAMADA, Yasuhiro SAITO and Hidemasa HIDAKA
Journal of Japanese society Nutrition and Food science, Vol. 46, No. 2, 123-129 (1993)
The effects of administration of Lactose (LA), fructooligosaccharides and other oligosaccharides (galactooligosaccharides: GO, isomaltooligosaccharides: IM, raffinose: RF) in the diet on absorption of calcium (Ca), magnesium (Mg) and phosphorus (P) in weanling male rats were examined by in vivo studies. In rats fed FO diet, Ca, Mg and P absorption were significantly higher than in rats fed the LA diet. FO had dose-dependent effect on minerals absorption (Exp.1). The enhancement of Ca, Mg and P absorption by FO persisted for as long as one month. A significant increase in the ash and mineral contents of the femur was observed in rats fed the FO diet, as compared with controls (Exp.2). FO had a positive effect on mineral absorption, and GO and RF had similar but somewhat variable effects. However, IM had no effect (Exp.3). There was a significantly positive correlation between mineral absorption and L-lactate concentration in the cecum. It was suggested that L-lactate concentration in the cecum had a direct effect on mineral absorption (Exp.3).
Atsutane OHTA, Masako OHTSUKI, Toshio TAKIZAWA, Hiromi INABA, Takashi ADACHI and Shyuichi KIMURA
International Journal for Vitamin and Nutrition Research Vol. 64, 316-323 (1994)
We reported previously that feeding of fructooligosaccharides (FO) increased the apparent absorption of calcium (Ca), magnesium (Mg) and phosphorus (P) in rats. We suggested that there was an important correlation between this phenomenon and fermentation of FO in the large intestine. However, the precise mechanism remained to be characterized. Therefore, we performed a mineral-balance study to identify the segment of lumen in which FO affects mineral absorption, using cecectomized rats. Sham-operated rats and cecectomized rats were fed a control diet (without FO) or an FO-diet (containing 50 G of FO per kg of feed) for 28 days. Feeding of the FO-diet decreased the luminal pH in the cecum and colon in the sham-operated rats. In the cecectomized rats, feeding of the FO-diet also decreased the luminal pH in the colon. Thus, FO was fermented in the colon of the cecectomized rats. However, the acid composition of feces was altered by cecectomy. Feeding of the FO-diet increased the absorption of Ca and Mg in the sham-operated rats. In the cecectomized rats, the FO-diet increased the absorption of Mg but did not increase the absorption of Ca. These results suggest the mechanisms for the absorption of Ca and Mg when rats are fed an FO are different.
Atsutane OHTA, Seigo BABA, Toshio TAKIZAWA and Takashi ADACHI
Journal of Nutritional Science and Vitaminology Vol. 40, 171-181 (1994)
Magnesium (Mg) is an essential dietary element that plays important roles, acting as cofactor of many enzymes. Rat fed a Mg-deficient diet have been reported to exhibit auricular and facial peripheral hyperemia and hemorrhage. Moreover, increased intake of calcium (Ca9 or phosphorus (P) has been reported to impair apparent absorption of Mg. We tried to induce such typical inflammation in Mg-deficient rats by feeding low-Mg, high-Ca and high-P diet. Increasing concentrations of Ca or P in the experimental diets significantly decreased the apparent absorption of Mg. And all rats fed Low-Mg (0.25mg.g diet), high-Ca(10.4mg/g diet) and high-P(12.0mg/g diet) diet exhibited auricular and facial peripheral hyperemia and hemorrhage. Then we used the low-Mg, High-Ca and high-P diet to investigate the effects of the fructooligosaccharides (FO) on absorption of Mg and skin inflammation. In the rats fed FO-containing (1 or 5%) diet, apparent absorption of Mg was significantly increased as compared with that of the control (FO 0%) group. In the rats fed a 5% FO-containing diet and sufficient Mg (0.50 mg/g), auricular and facial peripheral hyperemia and hemorrhage were significantly reduced. We concluded that FO increased the Mg absorption in rats fed a low-Mg, high-Ca and high-P diet. Moreover, FO reduced inflammation in Mg-deficient rats, such as peripheral hyperemia and hemorrhage.
Atsutane OHTA, Masako OHTSUKI, Seigo BABA, Toshio TAKIZAWA, Takashi ADACHI and Shuichi KIMURA
Journal of Nutritional Science and Vitaminology Vol. 41, 281-291 (1995)
We investigated the effects of fructooligosaccharides (FO)-feeding on the absorption of iron (Fe), calcium (Ca) and magnesium (Mg) and on the biochemical parameters in Fe-deficient anemic rats. Fe-deficient anemic rats were made by feeding an Fe-deficient diet for 3 weeks. Then these Fe-deficient rats were fed an experimental diet that contained one of two levels of Fe (15 or 30 mg/kg diet), in the form of ferric pyrophosphate, and one of two levels of FO( 0 or 50g/kg diet) for 2 weeks. After the rats were fed these experimental diets, FO-feeding increased the hemoglobin regeneration efficiency during the first week. Also, the apparent absorption of Fe was increased by FO-feeding. The levels of Fe in the diet did not affect the absorption of Ca and Mg. However, FO-feeding increased the absorption of Ca and Mg . FO-feeding lowered the pH and raised the solubility of Fe, Ca and Mg in the cecal contents, suggesting that those increasing effects of FO-feeding on absorption of these minerals is correlated with fermentation of FO in the large intestine, namely, the cecum and colon. We concluded that FO-feeding improved recovery from anemia and increased the absorption of Fe, Ca and Mg in Fe-deficient anemic rats.
Atsutane OHTA, Masako OHTSUKI, Seigo BABA, Takashi ADACHI, Takashi SAKATA, Ei SAKAGUTI
Journal of Nutrition Vol. 125, 2417-2424 (1995)
We investigated the effects of fructooligosaccharides (FO) on the absorption of Ca, Mg and water from the colon and rectum of rats, using chromium-mordanted cellulose as an unabsorbable marker to calculate apparent absorption of Ca and Mg. There was a positive correlation (r=0.982, P<0.001 in rats fed control diet, r=0.975, p<0.001 in rats fed FO-containing diet) between the amount of Cr and the dry weight of each fecal pellet in the colon and rectum. Ratios of Ca to Cr and Mg to Cr in fecal pellets in the colon and rectum were calibrated from Ca to Cr and Mg to Cr ratios of cecal contents. In rats fed the FO-containing diet, but not in rats fed the control diet (FO-free), these ratios were correlated with fractional length of transit (Lt) along the colon and rectum indicating linear disappearance of Ca and Mg during the colo-rectal passage. Total apparent absorption of Ca and Mg, predicted from regression equations with Ca to Cr and Mg to Cr ratios of cecal contents, agreed well with those calculated from Ca to Cr and Mg to Cr ratios of feces. FO-feeding did not affect net water absorption from the colon and rectum. The above results indicated that FO increased significantly Ca and Mg absorption, respectively, and that indigestive and fermentable carbohydrate facilitates colo-rectal absorption of Ca and Mg.
Atsutane OHTA, Seigo BABA, Masako OHTSUKI, Adusa TAGUTHI and Hiroshi HARA
British Journal of Nutrition (in press)
We developed a new type of anal cup for prevention of coprophagy to determine whether the absorption of calcium (Ca) and magnesium (Mg) and the stimulatory effects of feeding fructooligosaccharides (FO) on the absorption of Ca and Mg are altered by prevention of coprophagy in rats. Rats were fed on FO-free diet or 5% FO-containing diet for 2 weeks with or without prevention of coprophagy. FO-feeding increased the apparent absorptive ratio of Ca and Mg in rats with or without prevention of coprophagy. However, in the FO-fed groups, the absorptive ratio of Mg in rats with prevention of coprophagy was higher than in rats without prevention of coprophagy. The Ca content of the femur was higher in rats fed FO-diet than in rats fed FO-free diet both with and without coprophagy. In conclusion, FO-feeding increased the absorption of Ca and Mg in rats both with and without coprophagy. Moreover, prevention of coprophagy enhanced the absorption of Mg in rats fed FO. Coprophagy has to be considered when the effects of luminal fermentation or mineral absorption are examined in rats.
Nutrition Research (in press)
We investigated the effects of feeding fructooligosaccharides(FO) on the absorption of Mg from the hindgut in cecal-cannulated rats in vivo. Male rats, four wks old, were divided into four groups. Rats in two groups were fed Mg-containing diet and the other two groups were fed Mg-free diet with cecal infusion of Mg. Rats of both groups were fed FO-free or FO-containing diet, respectively. The absorptive ratio of Mg administrated into the cecum was similar to that of Mg fed orally in rats fed FO-free and FO-containing diet respectively. FO-feeding significantly increased the apparent absorption of Mg in both rats fed Mg orally and rats infused Mg into the cecum. Moreover, the extent of the increase in the absorption of Mg by infusion into the cecum and by oral feeding was same. In a separate experiment, we observed that only the rats fed Mg-free diet exhibited auricular and facial peripheral hyperemia and hemorrhage. However such symptoms were not observed in rats with Mg infused into the cecum. In conclusion, these results indicate that FO-feeding stimulates absorption of Mg mainly in the hindgut.
In Japan, FOS is available in commercial quantities
Meiji Seika Kaisha LTD.
In the U.S.A. it is available from:
Golden Technologies Inc.,
1660 School St.,
Moraga, CA 94556.
Tel: (510) 376-8200
In Europe, FOS is available from:
14, Bd du General Leclerc,
F 92572 Neuilly sur Seine Cedex,
Tel. (33-1)41 43 11 36
Fax: (33-1)41 43 13 02
Meiji Seika Kaisha, Ltd.
Sakado-Shi Saitama 350-02,
Phone : (81)492-84-7597
Fax : (81)492-84-7569
e-mail : MSC00130@niftyserve.or.jp
This page was first uploaded to The Magnesium Web Site on November 16, 1995