膳食纤维与结肠癌

近十几年来,膳食纤维的研究日益受到人们的重视。各国学者正广泛而深入地探讨其理化性质、生理功能及其与人体健康的关系。现仅就膳食纤维与结肠癌的关系及有关机理综述如下。一、膳食纤维与结肠癌发病的关系由于对膳食纤维在人体内的消化过程、降解程度、消化部位认识不一,故定义各异。目前为多数学者所接受的概念是:膳食纤维是植物性食物中不能     

膳食纤维与结直肠肿瘤的研究进展

长久以来,膳食纤维被认为可以降低结直肠肿瘤发生风险.膳食纤维做为益生元,被肠内益生菌酵解,可产生多种短链脂肪酸,降低肠内致癌物浓度,加速致癌物的排出,影响胆汁酸代谢.但有少数前瞻性研究结果并不支持该假说,其抗结直肠肿瘤作用的机制尚需要进一步研究.     

膳食纤维与健康

近年研究发现，膳食纤维具有防治先天性儿童慢性便秘、控制体重、控制和改善糖尿病预后、抑制肿瘤生长、改善肠道微环境和提高机体免疫力的作用，并提出了膳食纤维供应能量的结肠消化的概念，本文拟对此进行阐述。     

膳食纤维与肠内营养

膳食纤维（ｄｉｅｔａｒｙｆｉｂｅｒ，ＤＦ）一词始见于Ｈｉｐｓｌｅｙ（１９５３）“膳食纤维与妊娠毒血症”一文，其称经流行病学调查，证实妊娠毒血症与膳食中的植物细胞壁（含ＤＦ）有关。当时并未引起人们普遍的关注。以后，陆续发现富含水果与蔬菜的膳食具有降低胆...     

膳食纤维与无机盐的吸收

无机盐的吸收直接影响体内无机元素状态,它是一个复杂的生理过程,受许多因素的影响。近年来关于膳食纤维影响无机盐吸收的研究渐多,但未形成结论。膳食纤维是指植物细胞中不被人类消化酶消化因而不能被小肠吸收的部份,它包括:木质素、纤维素、半纤维素、果胶、树胶、粘胶等。膳食纤维主要存在于谷类、蔬菜和水果中。     

膳食纤维的保健功能

长期以来，许多人对膳食纤维毫无所知或知之不多，膳食纤维的保健作用一直没有在大众心目中引起足够的重视。因此，让更多的人了解膳食纤维的情况是有必要的。     

039 膳食纤维与健康

近年研究发现,膳食纤维具有防治先天性儿童慢性便秘、控制体重、控制和改善糖尿病预后、抑制肿瘤生长、改善肠道微环境和提高机体免疫力的作用,并提出了膳食纤维供应能量的结肠消化的概念,本文拟对此进行阐述.     

膳食纤维在糖尿病治疗中应用的研究进展

膳食纤维是指植物性食品中不能被人类胃肠道所消化的糖类物质。包括非淀粉类多糖和本质素，本文从膳食纤维的主要来源、生理作用以及在临床中的应用进行了分析。并探讨了膳食纤维在糖尿病治疗中的可能作用机制。     

膳食纤维分析方法的简化

对ＳｅｌｖｅｎｄｒａｎＲＲ等人的冷中性洗涤剂纤维提取分析法（ＣＮＤＦ）进行简化，改变了各溶剂的处理时间，省去了湿球研磨与超声波处理步骤。将原法中ＳＬＳ－ＰＡＷ－ＤＷＳＯ处理时间１５ｈ，３０ｍｉｎ和１６ｈ分别延长为２２ｈ，４０ｍｉｎ与２２ｈ，化学分析与透射电镜观察结果表明，简化法对膳食纤维的提取分析效果与原推荐法相同，更加方便与实用。     

Dietary Fiber and Colorectal Cancer: What Is Appropriate Advice?

Two recent studies question the role of dietary fiber in the prevention of colorectal cancer. However, the duration of dietary intervention, dose of fiber, and the complexity of polyp formation and transformation to carcinomas make interpretation of such studies difficult. Multiple rationales exist for promoting the consumption of high-fiber, low-fat, fruit-and vegetable-rich diets.     

Diabetes and Dietary Fiber

Eight insulin-requiring diabetics demonstrated a significantly lower plasma glucose while eating a high- fiber diet.     

不同来源膳食纤维,钙与结直肠癌关系的研究

以一项基于全人群的营养流行病学病例对照研究数据，探讨不同食物来源的膳食纤维和钙与结、直肠癌联系性的可能差异。结果表明，蔬菜类膳食纤维与左、在半结肠癌和直肠癌，水果类膳食纤维与右半结肠癌均呈显著负相关；动物性膳食钙则具有降低左、右半结肠癌及直肠癌发病相对危险度的趋势。并经非条件Ｌｏｇｉｓｔｉｃ回归模型调整年龄、性别、总能量、维生索Ｃ、饱和脂肪酸等因素后上述联系仍然存在，提示为一类独立性变量。而谷类膳食纤维和植物性膳食钙的抗结直肠癌的保护性作用不显著。研究表明膳食纤维和钙对结直肠癌的保护性作用，不但与摄入量还与种类和来源密切相关。．．     

Whole Grain,Dietary Fiber,and Incidence of Endometrial Cancer in a Danish Cohort Study

Whole grains and dietary fiber might be inversely associated with endometrial cancer risk through their effects on sex hormone metabolism and body fat. We investigated whether a higher intake of whole grains and dietary fiber was associated with a lower incidence of endometrial cancer in the Diet, Cancer and Health cohort of 29,875 women aged 50–64 years at enrollment in 1993–1997. Information on diet and lifestyle was derived from self-administered questionnaires. The incidence rate ratios and 95% confidence intervals were estimated based on a Cox proportional hazards model. Of the 24,418 women included as cohort members, 217 had a diagnosis of endometrial cancer. No clear associations were found between intake of whole grains or dietary fiber and the incidence of endometrial cancer.     

Importance of Dietary Fiber in Childhood

Dietary fiber has important health benefits in childhood, especially in promoting normal laxation. Currently, children consume amounts of dietary fiber that appear to be inadequate for optimal health promotion and disease prevention. It is prudent to recommend that children older than 2 years of age increase dietary fiber intake to an amount equal to or greater than their age + 5 g/day. According to the “age + 5” rule dietary fiber intake would increase from 8 g/day at age 3 years to 25 g/day by age 20 years. After age 20, dietary fiber levels of 25 to 35 g/day are recommended. Dietary fiber intake should be increased gradually in childhood by increasing consumption of a variety of fruits, vegetables, legumes, cereals, and other whole-grain products. Although very high fiber intake in childhood could have adverse effects, the potential health benefits of a moderate increase in dietary fiber substantially outweigh the possible risks, especially in highly industrialized countries such as the United States. A safe range of dietary fiber intake for children may be between age + 5 and age + 10 g/day. This range is considered safe even for children and adolescents with marginal intakes of some vitamins and minerals; should provide enough dietary fiber for normal laxation; and may provide enough added dietary fiber to help prevent chronic diseases.J Am Diet Assoc. 1995; 1140-1146, 1149.     

No Preventive Effect of Dietary Fiber Against Colon Cancer in the Japanese Population: A Cross-Sectional Analysis

The report of Fuchs et al. in 1999 on the protective effects of dietary fiber (DF) against colon carcinogenesis has led many researchers to question the benefits of DF. We analyzed the relationship between dietary intake and mortality from colon cancer in Japan cross-sectionally. Dietary data were taken from the National Nutrition Survey. The standardized mortality ratio (SMR) was calculated using data from "Vital Statistics" and "the Population Census in Japan." Multiple regression analysis (stepwise variable selection method) was performed with the SMR of colon cancer as the objective variable and intake of DF, nutrients, and food groups in 1966 as the explanatory variables. The beta regression coefficient was significantly positive for intakes of fat, protein, and vitamin C and significantly negative for intakes of calcium and vitamin A to the SMR of colon cancer. However, no significant correlation was observed for DF or for any of the various food groups analyzed. In conclusion, our data do not demonstrate any protective effect of DF on colon cancer in subjects with a low fat intake (Japanese subjects), which supports Fuchs' findings in subjects with high fat intake (U.S. subjects).