Department of Food Science and Nutrition, University of Minnesota, 1334 Eckles Avenue, St. Paul, MN 55344, USA.
Nutrients. 2013 Apr 22;5(4):1417-35. doi: 10.3390/nu5041417.
The health benefits of dietary fiber have long been appreciated. Higher intakes of dietary fiber are linked to less cardiovascular disease and fiber plays a role in gut health, with many effective laxatives actually isolated fiber sources. Higher intakes of fiber are linked to lower body weights. Only polysaccharides were included in dietary fiber originally, but more recent definitions have included oligosaccharides as dietary fiber, not based on their chemical measurement as dietary fiber by the accepted total dietary fiber (TDF) method, but on their physiological effects. Inulin, fructo-oligosaccharides, and other oligosaccharides are included as fiber in food labels in the US. Additionally, oligosaccharides are the best known "prebiotics", "a selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microflora that confers benefits upon host well-bring and health." To date, all known and suspected prebiotics are carbohydrate compounds, primarily oligosaccharides, known to resist digestion in the human small intestine and reach the colon where they are fermented by the gut microflora. Studies have provided evidence that inulin and oligofructose (OF), lactulose, and resistant starch (RS) meet all aspects of the definition, including the stimulation of Bifidobacterium, a beneficial bacterial genus. Other isolated carbohydrates and carbohydrate-containing foods, including galactooligosaccharides (GOS), transgalactooligosaccharides (TOS), polydextrose, wheat dextrin, acacia gum, psyllium, banana, whole grain wheat, and whole grain corn also have prebiotic effects.
膳食纤维的健康益处早已为人所赞赏。较高的膳食纤维摄入量与较少的心血管疾病有关，膳食纤维在肠道健康中发挥作用，许多有效的泻药实际上是分离的纤维来源。较高的膳食纤维摄入量与较低的体重有关。最初膳食纤维仅包括多糖，但最近的定义将低聚糖也包括在膳食纤维中，不是基于它们作为膳食纤维的化学测量值，而是基于它们作为被接受的总膳食纤维 (TDF) 方法的膳食纤维的生理效应。在菊粉、果寡糖和其他低聚糖在美国被包括在食品标签的纤维中。此外，低聚糖是最著名的“益生元”，“一种选择性发酵的成分，可使胃肠道微生物群的组成和/或活性发生特定变化，从而为宿主的健康和福祉带来益处。”迄今为止，所有已知和可疑的益生元都是碳水化合物化合物，主要是低聚糖，已知在人类小肠中抵抗消化，并到达结肠，在那里被肠道微生物群发酵。研究提供了证据表明，菊粉和低聚果糖（OF）、乳果糖和抗性淀粉（RS）符合定义的所有方面，包括双歧杆菌的刺激，双歧杆菌是一种有益的细菌属。其他分离的碳水化合物和含碳水化合物的食物，包括半乳寡糖（GOS）、转半乳寡糖（TOS）、聚右旋糖、小麦糊精、阿拉伯胶、车前子、香蕉、全麦小麦和全谷物玉米也具有益生元作用。
