Yeast Mannan Supplementation Provides Some Sleep Benefits, More Studies Needed

Supplementation with the prebiotic yeast mannan (YM) has demonstrated the potential to benefit both gut health and sleep quality, according to a study published in Nutrients.

Maintaining a healthy gut environment carries implications for one’s overall mental and physical health. When the gut environment is not nourished properly, this imbalance can lead to consequences that contribute to sleep problems, which can have a cascading impact on one’s overall health and well-being.

Gut Health Supplements Concept | image credit: Fabio - stock.adobe.com

A prebiotic is a substrate that is used by microorganisms to derive health benefits for their host. As the present authors mention, the utilization of prebiotics has gained increasing traction because they are easy to administer, have a low risk for severe adverse effects, and yield great potential for benefiting the functionality and makeup of an individual’s intestinal microbiota. YM, in particular, has been shown to alter intestinal microflora in ways that can impact sleep quality and encourage the growth of Bacteroides, such as Bacteroid thetaiotaomicron, that elevate the health status of the gastrointestinal microbiome.

With little research attention being given to the effects of YM supplementation, the present authors utilized fecal metabolomics to better investigate the direct effects and health benefits of YM on sleep quality and gut health.

The researchers recruited participants from the Department of Medical Management and Informatics in Hokkaido Information University, Japan. Participants were randomly assigned 1:1 to a placebo or YM group. From May 2021 to November 2021, blood and fecal samples were taken, physical exams and medical interviews were conducted, dietary surveys were given, and electroencephalogram (EEG) data to measure sleep quality were collected at various weeks. Five placebo or YM tablets were instructed to be taken once daily and participants kept logs on their bowel movements, physical status, menstrual status, tablet intake, and other medications they were taking.

The study began with 39 individuals who were instructed to carry out their daily lives as normal—but to avoid other health supplements. The authors found that changes in the frequency of defecation (times/day) were much greater in YM individuals compared with placebo (P = .037), as were changes in defecation volume (P = .013). Prior to treatment, YM frequency was 0.75 times per day compared with 0.81 times per day in placebo, demonstrating the benefits of YM on daily bowel habits. Furthermore, in the fecal metabolite analysis, those in the YM group demonstrated significant changes in the growth (P = .046) and relative abundance (P = .035) of B thetaiotaomicron.

EEG sleep measurements after 4 weeks of treatment revealed that the duration of stage N3 sleep (deep sleep) was significantly longer in the YM group vs placebo (P = .022). In a similar trend, N3 latency time was significantly shorter for those in the YM group vs those taking placebo (P = .008). Notably, there were no significant differences between groups at baseline, which suggested the inherent benefits of YM supplementation on individual sleep quality.

The authors subsequently conducted a forward stepwise linear regression analysis to evaluation the associations between fecal metabolites and sleep. Results showed that the extension of an individual’s total time in bed could be 53% attributed to elevations in fecal propionate levels (P < .0001). N3 latency was seen to be 59% affected by increases in gamma-aminobutyric acid (GABA; P = .001) and deoxythymidine monophosphate (P = .004) levels. Concentrations of GABA alone was seen to influence 33% of N3 latency (P = .007).

Although their study did not find significant correlations between YM supplementation and sleep latency or sleep efficiency, the authors concluded by emphasizing YM’s significant impact on deep sleep by helping individuals achieve N3 faster and for longer periods of time. To better understand the mechanisms at work in YM and more fully explore its benefits to the gut and individual sleep, more studies are needed.

Reference

Tanihiro R, Yuki M, Sasai M, et al. Effects of prebiotic yeast mannan on gut health and sleep quality in healthy adults: a randomized, double-blind, placebo-controlled study. Nutrients. 2023;16(1):141. doi:10.3390/nu16010141