Lipid excretion, fecal, effect

The mechanism whereby dietary protein influences DMH carcinogenesis is unknown. An attractive hypothesis concerning the effects of dietary protein on DMH metabolism is discussed later in this manuscript. Another factor which may contribute to tumor growth promotion in the intestine is a doubling of fecal crude lipid excretion which we observed in mice as dietary protein was increased from 10 to 40% of the diet (19). The association between... 

Dietary supplementation with 40 mg of manganese increased both fecal excretion and whole blood concentration of the mineral but had no effect on serum lipids or fecal fat. 

Kay, R.M. and Truswell, A.S. 1977. Effect of citrus pectin on blood lipids and fecal steroid excretion in man, Am. J. Clin. Nutr., 30 171-175. 

Various mechanisms have been proposed to explain the hypocholesterolemic effect of GA (Annison et al., 1995 Tiss et al., 2001). Some studies have suggested that the viscosity of fermentable dietary fiber contributes substantially to the reduction of lipids in animals and humans (Gallaher et al., 1993 Moundras et al., 1994). However, other studies suggested that this property is not related to plasma lipids (Evans et al., 1992). The mechanism involved is clearly linked to increased bile acid excretion and fecal neutral sterol or a modification of digestion and absorption of lipids (Moundras et al., 1994). 

Several other agents have beneficial effects on plasma lipid profiles occurring through various cellular mechanisms.89 Cholestyramine (Questran), for example, attaches to bile acids within the gastrointestinal lumen and increases the fecal excretion of these acids. This action leads to decreased plasma cholesterol concentrations because cholesterol breakdown is accelerated to replace the bile acids that are lost in the feces. 

In conclusion, serum, liver and brain lipid concentrations, body weight change and fecal fat excretions were greater in rats fed a diet with 25% fat than in rats fed a lower fat diet. Within each level of fat, total liver lipids decreased and liver cholesterol concentration increased as level of dietary manganese increased. However, in 14 adult, human subjects fed two levels of dietary fat, dietary manganese had no effect on serum lipid parameters or fecal fat excretion. 

Effects of dietary fiber on plasma lipids have been most pronounced and most consistent in studies using purified, viscous types of fiber, such as pectin and guar gum. The decrease in total and LDL cholesterol when feeding these fibers is accompanied by an increased fecal bile-acid excretion. Increased bile-acid loss with increased de novo synthesis from cholesterol is usually considered the main mechanism by which dietary fiber may alter plasma cholesterol. However, decreased absorption of dietary cholesterol or altered cholesterol and lipoprotein metabolism by other mechanisms may also be important (for review see for instance. ... 

The overall movement of fats in the rats during the last 3 days of the experiment are shown in Table 4. No significant differences between the diet groups were seen for any of the variables food intake, fat intake, dried feces mass, fat excretion, fat content of dry feces, or fat absorption coefficient. To see whether dietary DAG had any effects on the lipid composition of the feces, we also analysed the fecal lipid profiles of the two groups of rats using gas chromatography. No significant differences were found. 

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