Disease relevance of Dietary Fiber

• PURPOSE: We conducted a clinical trial to assess the effects on the incidence of adenomas of reducing dietary fat to 25% of total calories and supplementing the diet with 25 g of wheat bran daily and a capsule of beta carotene (20 mg daily) [1].
• AGA technical review: impact of dietary fiber on colon cancer occurrence [2].
• Because butyric acid (BA) is the major short-chain fatty acid produced by fermentation of dietary fiber in the large bowel, it may be an important regulator of apoptosis in colorectal cancer [3].
• Whereas both the amount and type of dietary fiber influence cholesterol and bile lipid metabolism, specific associations between fiber and gallstones in humans remain elusive [4].
• Last, both secoisolariciresinol and matairesinol are metabolized in the gut of mammals, following digestion of high fiber dietary grains, seeds, and berries, into the so-called "mammalian" lignans, enterodiol and enterolactone, respectively; these in turn confer significant protection against the onset of breast and prostate cancers [5].

Psychiatry related information on Dietary Fiber

• RESULTS: Body mass index and intake of refined sugars were directly associated with risk of gallstone formation, whereas physical activity, dietary monounsaturated fats, dietary cholesterol, and dietary fibers from cellulose were inversely associated with risk of gallstone formation [6].
• CONCLUSION: To control tHcy, decreasing coffee and alcohol consumption may be important in women, whereas increasing physical activity, dietary fiber, and folate intake may be important in men [7].
• Feeding behavior changes of cattle during introduction of monensin with roughage or concentrate diets [8].

High impact information on Dietary Fiber

• Human colonic bacteria ferment RS and nonstarch polysaccharides (NSP; major components of dietary fiber) to short-chain fatty acids (SCFA), mainly acetate, propionate, and butyrate [9].
• However, it is not known whether oat-bran diets lower serum cholesterol levels by replacing fatty foods in the diet or by a direct effect of the dietary fiber contained in oat bran [10].
• We evaluated in detail usual intake of vegetables and fruits (each measured as the total reported grams consumed for all queried vegetables and fruit), vitamins C and E, folic acid, individual carotenoids, and dietary fiber with its components [11].
• This inverse association was found to be independent of vitamin C,alpha-tocopherol, folic acid, dietary fiber, and alpha-carotene.Adjusting for beta-carotene or lutein + zeaxanthin somewhat attenuated the inverse association with vegetable intake [11].
• Effects of dietary fiber on N-nitrosomethylurea-induced mammary tumors and on plasma estrogen levels in rats [12].

Chemical compound and disease context of Dietary Fiber

• It is yet unclear which lipid(s) may be active in the carcinogenic process, but one promising hypothesis concerns the interaction of cholesterol metabolites, considered a risk factor for colon cancer, and dietary fiber which may have a protective role [13].
• The purpose of the present study was to investigate whether three different types of dietary fiber, wheat bran, carrot fiber, and citrus pectin, influenced the induction of colorectal tumors produced by 1,2-dimethylhydrazine in rats [14].
• A 3 x 3 factorial experiment was conducted to examine how dietary fiber (wheat bran) and fat (lard) interactively affect the genesis of N-methyl-N'-nitro-N-nitrosoguanidine-induced colon cancer in rats [15].
• The mean daily intakes of water (in food and beverages), magnesium, potassium, dietary fiber and ascorbic acid were greater in patients with hyperoxaluria than in stone formers with normal oxalate excretion [16].
• The aim of this study was to test whether a diet with a high level of fermentable dietary fiber can stabilize interprandial blood glucose and insulin levels, prevent declines below basal levels, and reduce physical activity in limited-fed breeding sows [17].

Biological context of Dietary Fiber

• Modulation of colonic epithelial cell proliferation, histone acetylation, and luminal short chain fatty acids by variation of dietary fiber (wheat bran) in rats [18].
• Effect of structured dietary fiber on bioavailability of amoxicillin [19].
• Long-term effects of dietary fiber on glucose tolerance and gastric emptying in noninsulin-dependent diabetic patients [20].
• These results suggest that the secretion rate of apo B, compositional changes in lipoproteins occurring in the intravascular compartment, and up-regulation of LDL receptors-associated with faster LDL apo B turnover rates-are secondary metabolic responses induced by dietary fiber that contribute to the lowering of plasma cholesterol concentrations [21].
• In male guinea pigs, alterations in hepatic cholesterol homeostasis induced by dietary fiber in part account for the decrease in plasma LDL levels (Fernandez et al. 1994. Am. J. Clin. Nutr. 59: 869-878; 1995. 61: 127-134, and J. Lipid Res. 1995. 36: 1128-1138) [22].

Anatomical context of Dietary Fiber

• The effect of meat protein and dietary fiber on colonic function and metabolism. II. Bacterial metabolites in feces and urine [23].
• Concentrations of Cu, Fe, Zn, Ca, and phytate were measured in dry-milled corn bran, wheat brans, and soybean hulls prior to being baked in bread and after passage through the human GI tract [24].
• Cell walls of spinach, beetroot, sweet corn, pineapple, and wheat bran contained the phenolic acids (ferulic, p-coumaric, and diferulic) bound to polysaccharide components [25].
• This study demonstrated that dietary fiber can decrease apparent nutrient absorption and increase transit time in the upper gastrointestinal tract without affecting apparent glucose absorption [26].
• Epidemiological studies have linked dietary fiber to the prevention of human colorectal cancer and suggest that short chain fatty acids such as butyric acid, which is produced by fermentation of dietary fiber in the large intestine, may be an important mediator of the protective effects of fiber [27].

Associations of Dietary Fiber with chemical compounds

• BACKGROUND: Epidemiologic evidence of associations between the high intake of fat and low intake of dietary fiber, beta carotene, and other dietary constituents and the risk of colorectal neoplasia has been inconsistent and has not provided a sufficient basis for recommendations concerning the dietary prevention of large-bowel cancer in humans [1].
• The percent of the carcinogen 1,2-dimethylhydrazine (DMH) bound to a variety of fibers, such as wheat bran, corn bran, citrus pulp, citrus pectin, and alfalfa, was examined at pH values ranging from 1 to 12 [28].
• Effect of dietary fiber on azoxymethane-induced intestinal carcinogenesis in rats [29].
• The interaction of dietary fibers and cholesterol upon the plasma lipids and lipoproteins, sterol balance, and bowel function in human subjects [30].
• 0. Results from this experiment showed that the affinity to various types of dietary fibers for the colon carcinogen DMH was differentially affected by pH [28].

Gene context of Dietary Fiber

• In vivo, increasing dietary fiber increased colonic, but not proximal, ileal hsp25 while having no effect on hsp72 or hsc73 expression [31].
• Sodium butyrate (NaB), a short chain fatty acid, is a HDAC inhibitor and is produced in the colonic lumen as a consequence of microbial degradation of dietary fibers [32].
• Min mice were fed the following high-fat (40% of energy) diets for 5-6 weeks; a high-beef diet and a casein-based diet without added fiber or casein-based diet with 10% (w/w) oat, rye or wheat bran, or 2.5% (w/w) inulin [33].
• However, butyrate, an important luminal component produced from fermentation of dietary fibers, is an efficient inducer of GSTs and especially of GSTM2 [34].
• Consumption of saturated fat was found to decrease, and intake of omega-3 polyunsaturated fatty acids and of dietary fiber was found to increase circulating IGFBP-3 concentrations [35].

Analytical, diagnostic and therapeutic context of Dietary Fiber

• These data indicate that substantial changes in fiber content of the diabetic diet may lead to marked changes in diabetic control and that increasing dietary fiber may be a useful means of lowering plasma glucose in some diabetic patients [36].
• Cholesterol-lowering effects of dietary fiber: a meta-analysis [37].
• We have studied the effect of brown rice and soybean dietary fiber on the oral glucose tolerance test, plasma-insulin, -glucagon, -triglycerides, and cholesterol levels in control and streptozotocin-induced diabetic rats [38].
• The use of dietary fiber to increase fecal excretion of retained metabolites in CRF may be a beneficial adjunct to a low-protein diet (LPD) [39].
• OBJECTIVE: A cross-sectional analysis of dietary fiber intake was performed in European type 1 diabetic patients enrolled in the EURODIAB IDDM Complications Study to explore its potential relationship to serum cholesterol levels and the prevalence of cardiovascular disease (CVD) [40].

References