Soluble Corn Fiber Increases Calcium Absorption Associated with Shifts in the Gut Microbiome: A Randomized Dose-Response Trial in Free-Living Pubertal Females.

BACKGROUND: Soluble corn fiber (SCF; 12 g fiber/d) is shown to increase calcium absorption efficiency, associated with shifts in the gut microbiota in adolescent males and females who participated in a controlled feeding study.

We evaluated the dose response of 0, 10, and 20 g fiber/d delivered by PROMITOR SCF 85 (85% fiber) on calcium absorption, biochemical bone properties, and the fecal microbiome in free-living adolescents.

Healthy adolescent females (n = 28; aged 11-14 y) randomly assigned into a 3-phase, double-blind, crossover study consumed SCF for 4 wk at each dose (0, 10, and 20 g fiber/d from SCF) alongside their habitual diet and were followed by 3-d clinical visits and 3-wk washout periods. Stable isotope ((44)Ca and (43)Ca) enrichment in pooled urine was measured by inductively coupled plasma mass spectrometry. Fecal microbial community composition was assessed by high-throughput sequencing (Illumina) of polymerase chain reaction-amplified 16S rRNA genes. Mixed model ANOVA and Friedman analysis were used to determine effects of SCF on calcium absorption and to compare mean microbial proportions, respectively.

Calcium absorption increased significantly with 10 (13.3% ± 5.3%; P = 0.042) and 20 g fiber/d (12.9% ± 3.6%; P = 0.026) from SCF relative to control. Significant differences in fecal microbial community diversity were found after consuming SCF (operational taxonomic unit measures of 601.4 ± 83.5, 634.5 ± 83.8, and 649.6 ± 75.5 for 0, 10, and 20 g fiber/d, respectively; P < 0.05). Proportions of the genus Parabacteroides significantly increased with SCF dose (1.1% ± 0.8%, 2.1% ± 1.6%, and 3.0% ± 2.0% for 0, 10, and 20 g fiber/d from SCF, respectively; P <0.05). Increases in calcium absorption positively correlated with increases in Clostridium (r = 0.44, P = 0.023) and unclassified Clostridiaceae (r = 0.40, P = 0.040).

SCF, a nondigestible carbohydrate, increased calcium absorption in free-living adolescent females. Two groups of bacteria may be involved, one directly fermenting SCF and the second fermenting SCF metabolites further, thereby promoting increased calcium absorption.



目的:PROMITOR SCF 85(食物繊維85%)を用いて、一日の食物繊維摂取量0、10および20gが食事制限のない被験者のカルシウム吸収、生化学的骨特性、および糞便中の微生物に与える用量応答を評価した。


結果:カルシウムの吸収は対照と比較して、食物繊維10g/日(13.3%±5.3%; P = 0.042)および食物繊維20g/日(12.9%±3.6%; P = 0.026)で有意に増加した。糞便中の微生物群の多様性の有意差は、SCFを摂取した後に見られた(それぞれ0,10、および食物繊維20g/日に対して601.4±83.5,634.5±83.8および649.6±75.5の操作分離単位測定; P <0.05)。Parabacteroides属の割合は、SCF摂取量に伴い有意に増加した(それぞれSCF由来の食物繊維0,10および20g/日に対して1.1%±0.8%、2.1%±1.6%および3.0%±2.0%; P <0.05)。カルシウム吸収の増加は、クロストリジウム(r = 0.44、P = 0.023)および未分類のクロストリジウム科(r = 0.40、P = 0.040)の増加と正の相関を示した。