The effect of dietary fiber supplementation in man. II. Alteration in fecal physiology and bacterial flora.

Fecal weight and water content and fecal quantitative and qualitative bacterial studies were compared on six volunteer subjects during regular diet periods and when on 5.4 g of diet fiber supplementation. There was a statistical mean stool weight increase for the group from 103 +/- 40 g to 226 +/- 90 g. The water content of the stool remained constant under the diet conditions of this study. The total anaerobic counts increased significantly while the subjects were on the high fiber diet. Trends in bacterial genus changes appeared but were not significant and total aerobic counts were stable.