Effects of inulin and lactose on fecal microflora, microbial activity, and bowel habit in elderly constipated persons

Abstract

Constipation is an ailment encountered often in elderly people. A study was initiated to test the effects of lactose or inulin on the bowel habits of constipated elderly patients and to correlate these effects with several variables measured in feces such as microflora composition, concentration of lactate and short-chain fatty acids (SCFAs), pH, and the activities of beta-glucosidase and beta-glucuronidase, Groups of 15 and 10 patients received lactose and inulin, respectively, for a period of 19 d. The dose, 20 g/d from days 1 to 8, was gradually increased to 40 g/d from days 9 to 11 and was kept at this dose from days 12 to 19. There was considerable interindividual variations with this kind of dietary intervention. Inulin increased bifidobacteria significantly from 7.9 to 9.2 log10/g dry feces, but decreased enterococci in number and enterobacteria in frequency. In individuals consuming lactose, a noticeable increase in fecal counts of enterococci and a decrease in lactobacilli and clostridia was detected. Total bacterial counts remained unchanged. No changes in the concentrations of fecal SCFAs and lactate were observed. SCFAs showed a slight trend toward higher molar ratios of acetate to butyrate in response to the intake of lactose or inulin. The fecal pH and the beta-glucosidase and beta-glucuronidase activities were not influenced by sugar intake. Inulin showed a better laxative effect than lactose and reduced functional constipation with only mild discomfort.

Removing lactose from milk does not delay bowel function or harden stool consistency in lactose-tolerant women

“…However, Kleessen et al (1997) found no differences in faecal pH after ingestion of 20 or 40 g of lactose per day. In the present study, there were significant carryover and period effects in faecal pH, and therefore only the results of the first treatment periods were taken into account.…”

“…In an earlier study, 0-8% of lactose was not absorbed in lactose-tolerant subjects (Bond and Levitt, 1976). Thus, lactose may have a slight laxative effect in the gastrointestinal tract in healthy subjects (Kleessen et al, 1997). In the same article, the authors reported that stool frequency increased and the percentage of faecal dry matter decreased in lactose-tolerant elderly volunteers in response to the ingestion of 20-40 g of lactose per day.…”

“…Both doses had a slight laxative effect, but the effect of the smaller dose was more marked. The researchers suggested that lactose can be used in the treatment of constipation (Kleessen et al, 1997). The study of Ewe et al (1995) does not, however, support the effectiveness of lactose in treating constipation.…”

“…In a double-blind, randomized clinical trial, the effect of 20 and 40 g/day of milk lactose was studied in 15 elderly constipated subjects (Kleessen et al, 1997). Both doses had a slight laxative effect, but the effect of the smaller dose was more marked.…”

The effect of high and low dietary crude protein and inulin supplementation on nutrient digestibility, nitrogen excretion, intestinal microflora and manure ammonia emissions from finisher pigs

“…If SCFAs are rapidly absorbed by the intestinal mucosa the concentration remaining in the digesta with potential to reduce pH is limited (Cummings et al, 1987;Alles et al, 1996). Other studies have also found no response in terms of intestinal pH or VFA concentration due to inulin supplementation Kleessen et al, 1997;Houdijk et al, 1997 and1998).…”