Department of Medical Physiopathology, Sapienza University of Rome, Rome, Italy.
Arch Gerontol Geriatr. 2009;49 Suppl 1:61-9. doi: 10.1016/j.archger.2009.09.013.
Dietary fiber can be considered "any dietary component that reaches the colon without being absorbed in a healthy human gut". Thus "fiber", according to the recent literature, is contemplated any substance other than plant cell-wall material. The latter is a new definition expanding the previous one beyond carbohydrates. In fact, there is evidence that compounds other than cell-wall polysaccharides that are able to evoke similar physiological effects of those stimulated by soluble and insoluble polysaccharides. Moreover, this definition does not presume that the physiological effects of any fiber component are manifested only when fiber reaches the colon. Dietary fiber intake is important from a metabolic view point (lipid and glucose metabolism) or acting as prebiotics on microbiota health, in preventing colonic cancer, in treating bowel diseases and symptoms, on mineral absorption. Fiber intake seems to be important in particular in the elderly to the point that all national dietary guidelines and food guide pyramid for elderly people underline the necessity to increase dietary fiber intake, and therefore fruits and vegetables.
膳食纤维可被视为“健康人体肠道中未被吸收而到达结肠的任何膳食成分”。因此，根据最近的文献，“纤维”被认为是除植物细胞壁物质以外的任何物质。这个新定义将以前的定义扩展到了碳水化合物之外。事实上，有证据表明，除了能够引起与可溶和不可溶多糖相似的生理效应的细胞壁多糖以外的化合物。此外，这个定义并不假设任何纤维成分的生理效应只有在纤维到达结肠时才会表现出来。膳食纤维的摄入从代谢角度（脂质和葡萄糖代谢）来看很重要，或者作为对微生物组健康的益生元，在预防结肠癌、治疗肠道疾病和症状、矿物质吸收方面也很重要。膳食纤维的摄入似乎对老年人尤为重要，以至于所有国家的膳食指南和老年人食物金字塔都强调必须增加膳食纤维的摄入，因此要多吃水果和蔬菜。
