EC Clinical and Medical Case Reports

Oats (Avena sativa L.) have gained increasing attention as functional foods due to their bioactive compounds; including β-glucans, resistant starch, arabinoxylan, polyphenols, and avenanthramides; which are known to modulate the gut microbiome and improve host health. Despite promising findings, substantial gaps remain-specific oat fractions are underexplored, few clinical trials span diverse populations, and only limited reviews have synthesized their effects on the gut microbiota and health outcomes. We present a 10-year systematic review to evaluate the effects of oat consumption on gut microbiota modulation and associated health benefits. A PubMed search was conducted, and 199 papers were identified within the past 10 years (1 May 2015 to 30 April 2025). After exclusions, a total of 80 primary research articles were included in this systematic review. The studies were categorised into three main themes: (a) effects of oat composition and processing techniques, (b) potential health benefits of oats mediated by gut microbiota, and (c) potential effects of other dietary ingredients on oats. Future research should focus on whole-food approaches preserving structural complexity, define dose-response relationships for health outcomes, and develop microbiome-based models to optimize personalized oat interventions.

 Keywords: Oats (Avena sativa L.); Gut Microbiome; Host Health; Gastrointestinal Disorders

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