Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Randomized Controlled Trial
. 2023 Jan-Dec;15(1):2197837.
doi: 10.1080/19490976.2023.2197837.

Effects of dietary fibers or probiotics on functional constipation symptoms and roles of gut microbiota: a double-blinded randomized placebo trial

Hao Lai  1 , Yunfeng Li  1 , Yafang He  1 , Fangyao Chen  1 , Baibing Mi  1 , Junqi Li  1 , Jiawen Xie  1 , Guoqing Ma  1 , Jinzhao Yang  1 , Kun Xu  1 , Xia Liao  2 , Yan Yin  3 , Junrong Liang  4 , Liyun Kong  1 , Xinyan Wang  5 , Zhongxia Li  5 , Yuan Shen  1 , Shaonong Dang  1 , Lei Zhang  1 , Qian Wu  1 , Lingxia Zeng  1 , Lin Shi  6 , Xuguang Zhang  5 , Tian Tian  7 , Xin Liu  1
Affiliations
Randomized Controlled Trial

Effects of dietary fibers or probiotics on functional constipation symptoms and roles of gut microbiota: a double-blinded randomized placebo trial

Hao Lai et al. Gut Microbes. 2023 Jan-Dec.

Abstract

Dietary fibers/probiotics may relieve constipation via optimizing gut microbiome, yet with limited trial-based evidences. We aimed to evaluate the effects of formulas with dietary fibers or probiotics on functional constipation symptoms, and to identify modulations of gut microbiota of relevance. We conducted a 4-week double-blinded randomized placebo-controlled trial in 250 adults with functional constipation. Intervention: A: polydextrose; B: psyllium husk; C: wheat bran + psyllium husk; D: Bifidobacterium animalis subsp. lactis HN019 + Lacticaseibacillus rhamnosus HN001; Placebo: maltodextrin. Oligosaccharides were also included in group A to D. 16S rRNA sequencing was used to assess the gut microbiota at weeks 0, 2, and 4. A total of 242 participants completed the study. No time-by-group effect was observed for bowel movement frequency (BMF), Bristol stool scale score (BSS), and degree of defecation straining (DDS), while BSS showed mean increases of 0.95-1.05 in group A to D (all P < 0.05), but not significantly changed in placebo (P = 0.170), and 4-week change of BSS showed similarly superior effects of the interventions as compared placebo. Group D showed a marginal reduction in plasma 5-hydroxytryptamine. Group A resulted in a higher Bifidobacterium abundance than placebo at week 2 and 4. Fourteen genera showed intervention-specific increasing or decreasing trends continuously, among which Anaerostipes showed increasing trends in groups B and C, associated with BMF increase. Random forest models identified specific baseline microbial genera panels predicting intervention responders. In conclusion, we found that the dietary fibers or probiotics may relieve hard stool, with intervention-specific changes in gut microbiota relevant to constipation relief. Baseline gut microbiota may predispose the intervention responsiveness. ClincialTrials.gov number, NCT04667884.

Keywords: Dietary fiber; functional constipation; gut microbiota; nutritional intervention; probiotics.

Plain language summary

What is the context?Supplementation of dietary fibers, such as psyllium husk or wheat bran (10 ~ 15 g/day) may relieve constipation symptoms, but bloating and flatulence are major concerns on a high fiber intake.Functional constipation patients had alternated gut microbiota profiles, while meta-analysis suggested that multispecies probiotics may increase bowel movement frequency and relieve hard stool in functional constipation.Dietary fibers or probiotics may lead to before-after changes of gut microbiota in patients with functional constipation, but time-series continued changes of gut microbiota during the intervention are unknown.Elevation of 5-hydroxytryptamine synthesis in enterochromaffin cells may affect bowel movement. And the elevated plasma 5-hydroxytryptamine was observed in functional constipation patients.What is new? Daily supplement of three prebiotic formulas with dietary fibers (polydextrose, psyllium husk, wheat bran, together with oligosaccharides), or a probiotic formula with Bifidobacterium animalis subsp. lactis HN019 + Lacticaseibacillus rhamnosus HN001 effectively relieved hard stool in functional constipation patients after 4 weeks intervention.We identified continued increasing or decreasing gut microbial genera over the intervention. Dietary fiber – gut microbiota (Anaerostipes)—constipation relieve (bowel movement frequency) evidence axis was identified in this human trial.Probiotic supplementation marginally reduced plasma 5-hydroxytryptamine, possibly associated with changes in BMF-related gut microbial genera.Intervention-specific baseline gut microbiota well predicted the responsiveness of constipation symptom relief.What is the impact? We provided references for the dosage and duration of dietary fiber/probiotics recommendations for adults with functional constipation, and advanced the microbial genera evidences of the fibers/probiotics-microbiota-laxation theory in humans.

PubMed Disclaimer

Conflict of interest statement

BYHEALTH Co., LTD provided the dietary fiber and probiotic supplements in this study.

Figures

None
Graphical abstract
Figure 1.
Figure 1.
The changes of constipation symptoms from baseline to week 2 and week 4 by group.
Figure 2.
Figure 2.
Changes in 5-HT and correlations with gut microbiota.
Figure 3.
Figure 3.
The baseline correlations between gut microbial abundance and constipation symptoms, and the difference in relative abundance of the top 10 genera between intervention groups and placebo group at different stages.
Figure 4.
Figure 4.
Constant genera abundance changes over the intervention and selected relevance with constipation.
Figure 5.
Figure 5.
Baseline gut microbiota predicting the improvement of constipation symptoms upon interventions.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Vriesman MH, Koppen IJN, Camilleri M, Di Lorenzo C, Benninga MA.. Management of functional constipation in children and adults. Nat Rev Gastroenterol Hepatol. 2020;17(1):21–15. doi:10.1038/s41575-019-0222-y. - DOI - PubMed
    1. Barberio B, Judge C, Savarino EV, Ford AC. Global prevalence of functional constipation according to the Rome criteria: a systematic review and meta-analysis. The Lancet Gastroenterol Hepatol. 2021;6(8):638–648. doi:10.1016/S2468-1253(21)00111-4. - DOI - PubMed
    1. Nag A, Martin SA, Mladsi D, Olayinka-Amao O, Purser M, Vekaria RM. The humanistic and economic burden of chronic idiopathic constipation in the USA: a systematic literature review. Clin Exp Gastroenterol. 2020;13:255–265. doi:10.2147/CEG.S239205. - DOI - PMC - PubMed
    1. Huang L, Jiang H, Zhu M, Wang B, Tong M, Li H, Lin MB. Prevalence and risk factors of chronic constipation among women aged 50 years and older in Shanghai, China. Med Sci Monit. 2017;23:2660–2667. doi:10.12659/MSM.904040. - DOI - PMC - PubMed
    1. Gill SK, Rossi M, Bajka B, Whelan K. Dietary fibre in gastrointestinal health and disease. Nat Rev Gastroenterol Hepatol. 2021;18(2):101–116. doi:10.1038/s41575-020-00375-4. - DOI - PubMed

Publication types

LinkOut - more resources