Stephen A M
Division of Nutrition and Dietetics, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada.
Crit Rev Food Sci Nutr. 1994;34(5-6):499-511. doi: 10.1080/10408399409527677.
Much of the present research on the physiological effects of dietary fiber and starch has been done on sources isolated from the parent material, and it is not clear whether they have the same effects if fed in the intact or whole grain. For dietary fiber, physiological effect depends on extent of fermentation in the large intestine, and this is influenced by chemical composition, solubility, physical form, and presence of lignin or other compounds. All of these factors are altered by isolation of a fiber source from the whole grain, and hence effects of eating fiber vary. Similarly, physical form and presence in the whole grain will affect digestibility of starch in the small intestine, which in turn influences the glycemic response and colonic effects determined by the extent of malabsorption and entry into the colon. Starch that enters the colon is fermented and produces short-chain fatty acids, particularly butyrate, which is necessary to maintain a healthy mucosa. Hence, their presence within the whole grain may have important implications for health for both dietary fiber and starch. Evidence indicates that such effects are beneficial and that whole-grain consumption should be encouraged.
目前关于膳食纤维和淀粉生理效应的许多研究都是针对从母体材料中分离出来的来源进行的，尚不清楚如果以完整谷物或全谷物形式喂食，它们是否具有相同的效果。对于膳食纤维来说，生理效应取决于在大肠中的发酵程度，而这会受到化学成分、溶解性、物理形态以及木质素或其他化合物的存在情况的影响。从全谷物中分离纤维来源会改变所有这些因素，因此食用纤维的效果也会有所不同。同样，物理形态以及在全谷物中的存在情况会影响淀粉在小肠中的消化率，进而影响血糖反应以及由吸收不良程度和进入结肠情况所决定的结肠效应。进入结肠的淀粉会被发酵并产生短链脂肪酸，特别是丁酸，这对于维持健康的黏膜是必需的。因此，它们在全谷物中的存在可能对膳食纤维和淀粉的健康都具有重要意义。有证据表明这些效应是有益的，应该鼓励食用全谷物。
