Abstract
- Background
Apples (Malus domestica) are exceptionally rich in bioactive dietary (poly)phenols and soluble dietary fiber, rendering them a valuable functional food associated with a reduced risk of chronic metabolic disorders. Emerging scientific evidence indicates that inter-individual variability in metabolic responses to specific dietary interventions may be partially explained by differences in host gut microbiota composition. However, whether apple-induced metabolic and microbial responses differ according to baseline gut enterotypes remains insufficiently elucidated. This 12-week single-blind intervention trial was designed to investigate enterotype-stratified associations between daily apple consumption, gut microbiota compositional profiles, and systemic metabolic parameters in a cohort of Japanese adults aged 40 to 65 years.
- Methods
A 12-week single-blind clinical intervention trial was conducted involving adult participants. Subjects were categorized into three distinct enterotypes based on family-level gut microbiota composition: Bacteroidaceae-dominant (ET1), Ruminococcaceae-dominant (ET2), and Prevotellaceae-dominant (ET3). Multivariable association analyses utilizing MaAsLin 3 were performed to identify microbial genera significantly associated with obesity and hyperlipidemia status, adjusting for repeated measures and relevant clinical covariates. Serial evaluations tracked systemic lipid- and glucose-related host parameters alongside fecal short-chain fatty acid (SCFA) concentrations before and after the daily apple consumption period.
- Results
Multivariable microbial association analyses identified five key genera significantly linked to obesity and hyperlipidemia status—namely Bifidobacterium, Lachnospira, Prevotella, Anaerostipes, and Dialister. While systemic lipid- and glucose-related host biochemical parameters did not exhibit statistically significant differences across enterotypes overall, fecal short-chain fatty acid concentrations increased significantly following apple consumption specifically in participants classified within the Bacteroidaceae-dominant enterotype (ET1).
- Conclusions
Daily apple consumption induces enterotype-dependent functional modifications, particularly evidenced by a selective elevation in fecal short-chain fatty acids within the Bacteroidaceae-dominant enterotype (ET1). These findings indicate that baseline gut microbiota structures modulate specific functional and metabolic responses to whole-fruit dietary interventions, underscoring the relevance of enterotype-dependent heterogeneity in metabolic adaptation.
https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2026.1797920/full