Associations of fruit, whole grain, and total energy intakes with gut microbiome diversity and composition

Background: The relationship between fruit, whole grain, and total energy consumption and the gut microbiome in the Chinese population remains unclear.

Objective: We investigated the relationship between intakes of fruits, whole grains, and energy, and the diversity and composition of gut microbiota.

Design: This cross-sectional study included 167 subjects aged 40-75 years who underwent colonoscopy at Nankai Hospital in Tianjin, China. Each of the participants completed a personal history questionnaire, a 7-day dietary record, and donated a fecal sample. The V3-V4 hypervariable region of the bacterial 16S rRNAgene was amplified and sequenced using Illumina Novaseq. The relationship between diet and gut microbiota was evaluated in terms of both the overall composition and the abundance of specific taxon.

Results: Fruits intake was positively related to the abundance of Bacilli, Porphyromonadaceae, Streptococcaceae, Parabacteroides, Streptococcus, and Bilophila in fecal samples. Higher whole grains intake was associated with higher microbial diversity, as measured by Shannon, Simpson, and Chao1 indices. Specifically, there was a significant increase inthe relative abundance of Lachnospiraceae and a decrease in Actinobacteria with increased whole grains intake. Moreover, higher intake of total energy was associated with a lower abundance of Anaerostipes and a higher abundance of Lactobacillales and Acidaminococcus.

Conclusion: Whole grains intake was positively associated with gut microbial diversity. Fruits and total energy intake were related to the abundance of specifictaxon (e.g., Bacilli and Acidaminococcus). These findings highlight the potential importance of dietary interventions for modulating gut microbiota composition and promoting overall health.