The effects of two dietary fiber supplements on gastrointestinal transit, stool weight and frequency, and bacterial flora, and fecal bile acids in normal subjects.

The effect of dietary supplements of sugar-cane fiber (bagasse), on stool weight, solids, and water content were studied in normal ambulant volunteers over a 9-mo period; a second inpatient study was done with bran supplements. The addition on 10.5 g of bagasse containing 5.1 g of crude fiber to a normal diet containing 3.7 g of crude dietary fiber daily raised the mean fecal weight from 88.3 +/- 6.4 g to 139.7 +/- 10.2 g/day (p less than 0.005). There was also a significant rise in fecal solids and fecal water, although the percentage of water in the stools remained unchanged. Bagasse supplements accelerated gastrointestinal transit when measured by the carmine marker technique. Radiopaque "shapes" showed a trend toward more rapid transit with bagasse supplements. Daily supplements of 39 g of wheat bran or 10.5 g of bagasse increased the total daily excretion of fecal bacteria, but there were no changes in bacteria excreted per gram of feces. The composition of the bacterial flora showed no change. There was increased excretion of fecal acid sterols on the bagasse supplement, but this failed to occur with bran. No changes attributable to fiber supplements occurred in the plasma triglycerides or cholesterol. Future work may define specific dietary fiber supplements for different therapeutic purposes. One fiber may be used as a bulk expander in diverticular disease and another as a hypocholesteremic fiber.