Vahouny G V
Fed Proc. 1982 Sep;41(11):2801-6.
Despite the physiochemical complexity of dietary fibers (plant cell walls) and their individual components, there is substantial epidemiologic, clinical, and experimental evidence that these dietary components may have a role in modifying certain risk factors in coronary heart disease. Particulate fibers, such as wheat bran, do not appear to significantly alter plasma lipids or lipoprotein distributions in humans, or the atherogenicity of diets in experimental animals. Dietary fibers found in fruits, legumes, and vegetables, in contrast, show more definitive responses. Among the fiber isolates, the gelling and mucilaginous fibers, such as pectins and guar gum, predictably decrease circulating lipids in humans and animals and increase excretion of fecal metabolites of cholesterol, the bile acids. These fibers and fiber components can be shown to influence luminal solubility of lipids and the extent of lymphatic absorption of both cholesterol and triglyceride. In addition, these same fibers are effective in reducing postprandial levels of glucose, insulin, and other hormones. These direct effects on lipid absorption, and secondary effects of glucose and insulin on hepatic and peripheral lipoprotein metabolism, can account for many of the hypolipidemic responses to specific dietary fibers or their components, and may be of long-term consequence in coronary heart disease.
尽管膳食纤维（植物细胞壁）及其各个成分在物理化学性质上很复杂，但有大量的流行病学、临床和实验证据表明，这些膳食成分可能在改变冠心病的某些危险因素方面发挥作用。颗粒状纤维，如麦麸，似乎不会显著改变人体血浆脂质或脂蛋白分布，也不会改变实验动物饮食的致动脉粥样硬化性。相比之下，水果、豆类和蔬菜中的膳食纤维表现出更明确的反应。在纤维分离物中，胶凝性和粘性纤维，如果胶和瓜尔豆胶，可预期地降低人和动物的循环脂质，并增加胆固醇（胆汁酸）粪便代谢物的排泄。这些纤维和纤维成分可被证明会影响脂质的管腔溶解度以及胆固醇和甘油三酯的淋巴吸收程度。此外，这些相同的纤维在降低餐后葡萄糖、胰岛素和其他激素水平方面也很有效。这些对脂质吸收的直接影响，以及葡萄糖和胰岛素对肝脏和外周脂蛋白代谢的间接影响，可以解释对特定膳食纤维或其成分的许多降血脂反应，并且可能对冠心病产生长期影响。
