Fiber-free diet

Experiments with chemically induced colon cancer in the rat have partially, but not consistently, supported the dietary fiber hypothesis (12). Thus, Bauer et al. (13,14) recently reported that both high- and low-methoxylated pectin (6.5 or 5% in a diet containing 20% casein, 20% fat and no other dietary fiber) given during induction of colon cancer with subcutaneous 1.2-dimethyl— hydrazine, enhanced the yield of tumors. Guar gum, 5%, also tended to increase the tumor yield, although not significantly compared with controls on a virtually fiber-free diet. Others(15) however reported a protective effect of 15% pectin. 

Acid hydrolysis of hitman fecal samples collected after Ingestion of different dietary fibers produced monosaccharides that were related to the fibers Ingested. Dietary fibers studied In five normal male subjects were cellulose, xylan, corn bran and pectin. Increases In monosaccharides In recovered hydrolyzed feces from fiber diets compared to those from the fiber-free diet were galactose for the pectin diet xylose and glucose for the cellulose diet xylose and mannose for the xylan diet and arablnose, xylose, galactose and glucose for the corn bran diet. Comparison of the fecal results to those for the Intact food fibers showed that fermentation of fiber components In the colon was different for each fiber. 

Figure 8. Comparison of fiber input to fecal output (dry weight in grams) corrected for fecal output from fiber-free diet shown at extreme right. Average of five subjects for 3-day total fecal output.

Based on the majority of the evidence provided in the scientific database, and despite the limitations, Health Canada and the Canadian Celiac Association (CCA) concluded that the majority of people with celiac disease can tolerate moderate amounts of pure oats. The incorporation of oats into a gluten-free diet provides high fiber and vitamin B content, increased palatability, and beneficial effects on cardiovascular health. However, it is recommended that individuals with celiac disease should have both initial and long-term assessments by a health professional when introducing pure oats into a gluten-free diet. 

Manganese is a nutritionally important trace element for chicks. Dietary energy and protein sources contain very little bioavailable Mn, and these feed ingredients reduce the biopotency of inorganic Mn supplements. This adverse effect is exerted primarily in the intestine as a result of reduced Mn absorption and is mediated by the fiber and/or ash components of the feedstuffs. Gut absorption efficiencies are higher when a phytate-and fiber-free casein-dextrose diet is fed than when a corn-soybean meal diet is fed. Dietary interrelationships exist between Mn and Co and between Mn and Fe. Cobalt increases Mn absorption and may precipitate Mn toxicosis. Excess dietary Mn reduces Fe utilization, but excess Fe does not affect Mn utilization. Eimeria acervulina infection increases Mn absorption. 

FIGURE 2.46 Activity of sucrase. Rats were fed diets that were high in sucrose (open bars) or were Ccirbohydrate free (filled bars). The sucrose diet contained 650 g sucrose per kilogram of food. The carbohydrate-free diet contained a mixture of nonnutritive fiber and com oil rather than sucrose. The animals were fed the diets for 4 days then the intestines were removed for assay of enzyme activity. The results demonstrate that enzyme activity was about threefold greater with the sucrose diet than with the carbohydrate-free diet. Separate experiments revealed that maximal adaption of sucrase activity to the diet required 0.5-1.0 days. (Redrawn with permission from Riby and Kretchmer, 1984.)... 

Oat bran did not change plasma cholesterol levels. Others (25) have shown that oat bran decreases total plasma cholesterol and increases HDL in cholesterol fed rats. The effect seems to be related to soluble oat gums. The lack of effect of oat bran in our experiment might be due to the fact that we studied this fiber only in cholesterol-free diets. Soluble gums may also have been lost in preparing this fiber enriched oat bran (81% dietary fiber). 

Pancreas weight and lipase activity in the intestines of rats adapted to a diet with cellulose (C) or fiber free (FF). 

ELEMENTAL DIETS (SEMISYNTHETIC FIBER FREE LIQUID DIETS) ... 

That same long-chain fatty-acid-free diet was used very successfully to treat a three family members who had bfelong weakness and fatty-food intolerance due to autosomal dominant lipid neuromyopathy (with excess hpid within muscle fibers and Schwann cells) and normal levels of muscle carnitine [58]. 

Lipids present in the diet may become rancid. When fed at high (>4-6%) levels, Hpids may decrease diet acceptabiUty, increase handling problems, result in poor pellet quaUty, cause diarrhea, reduce feed intake, and decrease fiber digestion in the mmen (5). To alleviate the fiber digestion problem, calcium soaps or prilled free fatty acids have been developed to escape mminal fermentation. These fatty acids then are available for absorption from the small intestine (5). Feeding whole oilseeds also has alleviated some of the problems caused by feeding Hpids. A detailed discussion of Hpid metaboHsm by mminants can be found (16). 

Antilipidemic activity. Triglycerides structured lipids from coconut oil, administered to rats at a dose of 10% of diet for 60 days, produced a 15% decrease in total cholesterol and a 23% decrease in LDL cholesterol levels in the serum compared to coconut oil-fed rats. Total and free cholesterol levels in the liver of structured lipid-fed rats were lowered by 31 and 36%, respectively. The triglycerides in the serum and liver were decreased by 14 and 30%, respectively " . Anti-nociceptive activity. Aqueous extract of the husk fiber, administered orally to mice at doses of 200 or 400 mg/kg, produced an inhibition of the acetic acid-induced writhing response . 

A resurgence of interest in dietary fiber has been stimulated by epidemiological evidence of differences in colonic disease patterns between cultures with diets containing large quantities of fiber, and Western cultures having more highly refined diets. Many African countries, for example, are relatively free of diverticular disease, ulcerative colitis, hemorrhoids, polyps, and cancer of the colon Whereas most interest has focused on the beneficial role of dietary fiber, there is also concern that high fiber diets may cause disturbances in the absorption of nutrients such as minerals (see Mineral Nutrients) and vitamins. 

Wheat starch is low in protein, ash and fiber, and contains no residual sulfites. Sulfur dioxide is detrimental to the viscoelastic character of wheat gluten and is not used in the commercial production of wheat starch.28,323 The protein content of ten samples of unmodified and modified wheat starches ranged from 0.06-0.22%.28 A 0.23% protein (0.0404% nitrogen) level in wheat starch essentially indicates a gluten-free starch, as confirmed by an enzyme immunoassay.324 That purity of wheat starch is important in diets for celiac individuals. Wheat starch-based, gluten-free flour products were not harmful in the treatment of celiac sprue and dermatitis herpetiformis,325 although traces of an immunoreactive gliadin can be found in wheat starch.326... 

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