Xylooligosaccharides promote optimal gut microflora balance in adults, study shows

Summary

This double-blind, randomized, placebo-controlled, pilot study assessed the effect of xylooligosaccharides (XOS) on the gut microbiota in healthy and pre-diabetic adults.

For this study, researchers randomly assigned 16 healthy men and women, 21-49 years of age, and 13 pre-diabetic men and women, 30-63 years of age, to receive one of two treatments: 2 g/day XOS or a placebo for 8 weeks. Stool samples were collected at baseline and after 8 weeks and analyzed for changes in gut bacteria. In the pre-diabetic subjects, changes in body composition and oral glucose tolerance test (OGTT) were also assessed.

Results reveal 40 bacterial taxa associated with pre-diabetes, including an abundance of Enterorhabdus, Howardella, and Slackia genera. XOS significantly decreased or reversed the increase in these three genera in both pre-diabetic and healthy subjects. In pre-diabetic subjects, Blautia hydrogenotrophica, a species found to be lower in pre-diabetic subjects, was increased by XOS treatment. XOS showed a tendency (P=.13) to reduce 2-hour OGTT insulin levels, but had no significant effect on blood glucose, body composition, HOMA-IR, triglycerides, satiety hormones, or the pro-inflammatory marker TNFα. Interestingly, in healthy subjects, XOS largely inhibited bacteria related to infectious and metabolic disease (e.g., Streptococcaceae, Clostridia, Subdoligranulum, Gordonibacter, and Streptococcus) and greatly reduced the abundance of bacteria related to obesity or type 2 diabetes (e.g., Firmicutes, Subdoligranulum and Bacilli). Participants did not report any adverse effects or symptoms with the XOS intervention.

These findings indicate that supplementing with 2 g/day XOS for 8 weeks significantly modifies gut microflora in healthy and pre-diabetic adults to promote a gut bacteria balance that is associated with health.