PDF(Pubmed)
Abstract：
A low-fibre diet leads to gut microbiota imbalance, characterized by low diversity and reduced ability to produce beneficial metabolites, such as short-chain fatty acids (SCFAs). This imbalance is associated with poor gastrointestinal and metabolic health. We aimed to determine whether one dietary change, substitution of white bread with high-fibre bread, improves gut microbiota diversity and SCFA-producing capability. Twenty-two healthy adults completed a two-phase randomized, cross-over trial. The participants consumed three slices of a high-fibre bread (Prebiotic Cape Seed Loaf with BARLEYmax®) or control white bread as part of their usual diet for 2 weeks, with the treatment periods separated by a 4-week washout. High-fibre bread consumption increased total dietary fibre intake to 40 g/d, which was double the amount of fibre consumed at baseline or during the white bread intervention. Compared to white bread, the high-fibre bread intervention resulted in higher faecal alpha diversity (Shannon, p = 0.014) and relative abundance of the Lachnospiracae ND3007 group (p < 0.001, FDR = 0.019) and tended to increase the butyrate-producing capability (p = 0.062). In conclusion, substituting white bread with a high-fibre bread improved the diversity of gut microbiota and specific microbes involved in SCFA production and may enhance the butyrate-producing capability of gut microbiota in healthy adults. These findings suggest that a single dietary change involving high-fibre bread provides a practical way for adults to exceed recommended dietary fibre intake levels that improve gut microbiota composition and support gastrointestinal and metabolic health.
摘要：
低纤维饮食导致肠道微生物群失衡，其特点是多样性低，产生有益代谢物的能力降低，例如短链脂肪酸(SCFA)。这种失衡与不良的胃肠道和代谢健康有关。我们的目的是确定一种饮食是否改变，用高纤维面包代替白面包，改善肠道微生物群多样性和SCFA生产能力。22名健康成年人完成了两个阶段的随机分组，交叉审判。参与者食用三片高纤维面包（含BARLEYmax®的益生元CapeSeedLoaf）或对照白面包，作为他们通常饮食的一部分，持续2周。治疗期由4周冲洗分开。高纤维面包的消费使总膳食纤维摄入量增加到40克/天，这是在基线或白面包干预期间消耗的纤维量的两倍。与白面包相比，高纤维面包干预导致更高的粪便α多样性(香农，p=0.014）和LachnospiracaeND3007组的相对丰度（p<0.001，FDR=0.019），并倾向于增加丁酸酯的生产能力（p=0.062）。总之,用高纤维面包代替白面包可以改善肠道微生物群和SCFA生产中涉及的特定微生物的多样性，并可能增强健康成年人肠道微生物群的丁酸酯生产能力。这些发现表明，涉及高纤维面包的单一饮食变化为成年人提供了一种实用的方法，可以超过推荐的膳食纤维摄入量，从而改善肠道微生物群组成并支持胃肠道和代谢健康。
