Types of fiber and gut microbiota composition and diversity among arab females

Abstract

Objectives: Dietary fiber is recognized as an important nutrient for gut health. However, research on the relations of different types of fibers (soluble and insoluble) to the human microbiota health is limited. This study aimed to identify whether higher habitual intake of soluble and/or insoluble fiber have a different influence on the composition, diversity, and abundance of microbiota.

Methods: We examined the fecal microbial composition of 92 healthy females aged 18 and above using the novel shotgun metagenomics sequencing technique. The habitual fiber intake was determined using the Saudi food frequency questionnaire. Pearson's correlation was used for the correlations between total, soluble, and insoluble fiber and gut microbiota. α- and β-diversities were applied to acquire the distinctions in the relative abundances of bacterial taxa.

Results: Our findings show that higher dietary fiber, particularly insoluble fiber, was significantly correlated with the abundances of Bacteroides_u_s, Bacteroides uniformis, and Lactobacillus acidophilus (r = 0.26, 0.29, 0.26, p-value < 0.05, respectively). Non-significant difference was noted in the microbial α-diversity and β-diversity in low and high soluble/insoluble dietary fiber.

Conclusions: Current findings suggest that insoluble dietary-fiber intake is favorably correlated with the health of the human gut microbiota. However, further investigations are necessary to identify the effect of types of fiber on the specific species identified in this study.

Keywords: BMI; Fiber; Gut microbiota; Obesity; Soluble/insoluble.

Fig. 1

Comparison of gut microbiota α-diversity by insoluble fiber intake using Simpson’s Diversity Index, p = 0.04.

Fig. 2

Principle coordinate analysis (PCoA) of β- diversity of gut microbiota relative to low and high insoluble fiber intake.

Fig. 3

Phylum-level classification of gut microbiota relative to insoluble fiber.