Barrie BC Calgary Durham Edmonton Guelph Halifax Hamilton Kingston Kitchener Lethbridge London Montreal New Brunswick Okanagan Ottawa Peterborough Regina Saskatoon Toronto Winnipeg. Global News Facebook Pages Global News Twitter Accounts Global News Youtube Channel Global News on Instagram Global News on LinkedIn Global News on TikTok Global News on Telegram.

Close Local your local region National. Share Share this item on Facebook facebook Share this item on Twitter twitter Send this page to someone via email email Share this item via WhatsApp whatsapp Share this item on Flipboard flipboard Share this item on LinkedIn linkedin Share this item on Reddit reddit Copy article link Copy link.

Calendar All event types Comedy Festival Food Health Music Sports Theatre Virtual Other. Search Submit search Quick Search. Add Global News to Home Screen Close Instructions: Press the share icon on your browser Select Add to Home Screen Press Add.

Comments Close comments menu. Video link. Close X. Click to scroll back to top of the page Back to top. By Katie Dangerfield Global News. Posted August 8, pm. Hide message bar.

Leave a comment Share this item on Facebook Share this item via WhatsApp Share this item on Twitter Send this page to someone via email See more sharing options. Descrease article font size. Increase article font size. Story continues below advertisement.

How the sleep study worked. Get the latest Health IQ news. Sent to your email, every week. Trending Now. A year-old went hiking alone in California.

Her body was recovered 8 days later. Shift workers need to pay special attention. More on Health. Journalistic standards Comment Report an error. Sponsored content. Meanwhile, the other mice — the control group — drank water without antibiotics.

After 4 weeks, the researchers found that the mice that drank the antibiotic water had far fewer intestinal metabolites than the control mice. The team found that the biological pathways that the antibiotic treatment most affected were those that play a role in producing neurotransmitters, the molecules that neurons use to communicate.

The results indicated that the antibiotic treatment totally shut down the tryptophan-serotonin pathway. The microbiota-depleted mice had higher tryptophan levels than the control mice but almost no serotonin. Therefore, it seems that gut microbes are critical to the process that produces serotonin from tryptophan in foods.

The microbiota-depleted mice were also deficient in vitamin B6 metabolites, which are molecules that speed up the production of serotonin and dopamine.

This step revealed that compared with the control mice, the microbiota-depleted mice experienced more rapid eye movement REM and non-REM sleep at night, a time when mice should be active.

The microbiota-depleted mice also had less non-REM sleep during the daytime, most of which mice usually spend sleeping. Finally, the team noted that the microbiota-depleted mice experienced a higher number of REM sleep episodes than the control mice during both the day and night and a higher number of non-REM episodes in the daytime.

These findings suggest that the microbiota-depleted mice were switching more frequently between sleep and wake stages than the control mice. The researchers believe that these sleep disturbances may be related to low serotonin levels, but more research is necessary to determine the mechanism.

The limitations of the study include the fact that the researchers could not disregard the direct effect of the antibiotics on brain function. The researchers suggest that one way to get around this in future studies is to use germ-free mice. Some research shows that prebiotics, which are nutrients that support a healthy intestinal microbiota, help improve sleep quality in humans.

Supplementation with prebiotics may also reduce stress-related sleep disturbances in rats. A person with insomnia can try various techniques to encourage the onset of sleep and improve its quality and duration.

Learn more here. The tens of trillions of microbes that live in the gut have some important implications for health, but do you know what they are? We investigate. Read this article to learn about the causes and treatment options available.

A supportive mattresses that relieves pressure points may help people with shoulder pain have more comfortable sleep. Discover some of the best…. Medium-firm mattresses may improve sleep quality and align the body. Learn more about the best options for here.

My podcast changed me Can 'biological race' explain disparities in health? Why Parkinson's research is zooming in on the gut Tools General Health Drugs A-Z Health Hubs Health Tools Find a Doctor BMI Calculators and Charts Blood Pressure Chart: Ranges and Guide Breast Cancer: Self-Examination Guide Sleep Calculator Quizzes RA Myths vs Facts Type 2 Diabetes: Managing Blood Sugar Ankylosing Spondylitis Pain: Fact or Fiction Connect About Medical News Today Who We Are Our Editorial Process Content Integrity Conscious Language Newsletters Sign Up Follow Us.

Medical News Today. Health Conditions Health Products Discover Tools Connect. How gut microbes contribute to good sleep.

By contrast, five bacterial taxa increased the risk of insomnia, namely, Rikenellaceae RC9 gut group OR: 1. Alistipes OR: 0. By contrast, five intestinal flora genera were positively correlated with sleep duration according to the IVW estimates, namely, Victivallis OR: 1.

The IVW estimates suggested that the genetic forecast of abundance ratio of Alistipes OR: 0. However, Slackia OR: 1. Coprococcus 1 OR: 0. Three genera were positively correlated with short sleep duration, namely, Eubacterium hallii group OR: 1.

Furthermore, the causal link between Anaerofilum and short sleep duration was still significant after Bonferroni correction. The IVW method yielded nominal associations of four intestinal flora genera with chronotype, namely, Bacteroides OR: 0.

Genetically predicted relative abundance of Intestinibacter OR: 1. After using the binary phenotype of the chronotype, the significant difference of all these associations persisted except for Eubacterium coprostanoligenes group OR: 0. Furthermore, nominal significant effects on chronotype were observed for Bifidobacterium OR: 0.

In addition, the influence of Tyzzerella 3 on chronotype was more significant. According to the selection criteria of the IVs, we selected 78 SNPs for daytime napping, 33 SNPs for daytime sleepiness, 34 SNPs for insomnia, 58 SNPs for sleep duration, four SNPs for long sleep duration, 23 SNPs for short sleep duration, and SNPs for chronotype.

Details about the selected SNPs are displayed in Supplementary Tables S5—S Except for IVs for long sleep duration and short sleep duration, the F-statistics for IVs were larger than As shown in Figure 3 and Supplementary Table S14 , the results of reverse MR analysis indicated that daytime napping was correlated with three bacterial taxa, daytime sleepiness was correlated with eight bacterial taxa, insomnia was correlated with five bacterial taxa, sleep duration was correlated with eight bacterial taxa, long sleep duration was correlated with four bacterial taxa, short sleep duration was correlated with eight bacterial taxa, and chronotype was correlated with five bacterial taxa.

Figure 3. In the reverse MR analysis, IVW estimates from seven sleep-associated traits daytime napping, daytime sleepiness, insomnia, sleep duration, long sleep duration, short sleep duration and chronotype on 39 bacterial genera. The IVW estimates indicated that daytime napping had causal contribution to the reduction of Fusicatenibacter abundance OR: 0.

The IVW estimates indicated that daytime sleepiness was negatively correlated with five bacterial taxa, namely, Oxalobacter OR: 0. In addition, there were suggestive associations between daytime sleepiness with three bacterial taxa, namely, Dialister OR: 2.

However, after additional adjustment for body mass index, the effects of daytime sleepiness on Slackia , Dialister , Blautia , Dorea , and Coprococcus 3 were not significant. Insomnia was negatively correlated with Eubacterium nodatum group OR: 0.

The results of the IVW method revealed that sleep duration was negatively correlated with five intestinal flora genera, namely, Senegalimassilia OR: 0.

It was positively correlated with three bacterial taxa, namely, Bacteroides OR: 1. The F-statistic of SNPs for long sleep duration and short sleep duration was less than Therefore, weak instrumental bias could disturb the conclusions of reverse MR analysis Supplementary Table S Chronotype was negatively correlated with the genetic forecast of abundance ratio of four bacterial taxa, specifically, Ruminococcus gnavus group OR: 0.

It was positively correlated with Streptococcus OR: 1. However, after using the binary phenotype of the chronotype, the associations of chronotype with Ruminococcus gnavus group , Butyricicoccus , and Ruminiclostridium 6 became insignificant. In addition, significant effects of chronotype on Eggerthella OR: 2.

In other words, there was no evidence of significant heterogeneity. To the best of our knowledge, this is the first bidirectional MR analysis that comprehensively clarifies causal relationships between gut microbiota and sleep-related traits.

As shown in Figures 2 , 3 , our findings indicate that a total of 68 bacterial taxa are causally associated with seven sleep-related traits. Furthermore, 13 bacterial taxa related to sleep-related features in forward MR analysis were regulated by sleep-related traits, including Alistipes , Alloprevotella , Anaerofilum , Bacteroides , Catenibacterium , Coprococcus 3 , Oxalobacter , Parabacteroides , Ruminiclostridium 6 , Ruminococcaceae NK4A group , Ruminococcaceae UCG , Ruminococcus gnavus group , and Slackia.

Nevertheless, the potential causal effects of Coprococcus 3 , Oxalobacter , and Slackia on daytime sleepiness, and the potential causal effect of Parabacteroides and Bacteroides on chronotype in forward MR analysis were not supported by the results of reverse MR analysis.

However, these findings did not exclude the possibility that the effects are interactive. Moreover, owing to potential pleiotropy, some causal effects Eisenbergiella on daytime napping, daytime napping on Fusicatenibacter , sleep duration on Lactobacillus , and binary chronotype on Alistipes were not credible.

After excluding the above uncertain causal effects, a total of 40 bacterial taxa had potential causal effects on seven sleep-related traits, which in the other direction may be related to 34 bacterial taxa, and most of the bacterial taxa were of Bacillota Figure 4.

Figure 4. The chord plot showed the causal relationships between gut microbiota and sleep. Growing evidence from observational studies indicates that gut microbiota is correlated with sleep-related traits and disorders, and that the absence of gut microbes and their metabolites may alter sleep traits and architecture Leone et al.

Szentirmai et al. found that the intestinal microbiome induces non-REM sleep through butyrate-sensitive mechanisms Szentirmai et al. Cross-feeding is the central metabolic mechanism of the gut microbiota.

Faecalibacterium can produce butyrate from acetate and lactate, which are produced by Bifidobacteria from fermented carbohydrates. Moreover, the coculture of Eubacterium hallii group with Bifidobacterium promotes the accumulation of butyrate through cross-feeding Belenguer et al.

Butyricimonas , Marvinbryantia , Holdemanella , Intestinibacter , Ruminococcaceae NK4A group , Clostridium sensu stricto 1 , and Oscillibacter have also been associated with the production of butyrate, while Eggerthella is involved in the depletion of butyrate Chen et al.

Consistent with these previous studies, our study found that these butyrate-producing bacteria Bifidobacterium , Clostridium sensu stricto 1 , Eubacterium hallii group , Holdemanella , Intestinibacter , Marvinbryantia , Oscillibacter , and Ruminococcaceae NK4A group all had a nominally significant causal association with sleep Figure 5.

This finding suggests that these intestinal microbiotas associated with butyrate metabolism are involved in sleep-related regulatory mechanisms Figure 6. Lipopolysaccharides and peptidoglycans, which are components of bacterial cell walls, are released during the decomposition or division of bacteria and then produce an inflammatory response by activating the expression of proinflammatory factors Motta et al.

Previous research has confirmed that these inflammatory responses are related to the sleep that occurs during bacterial infections. However, the butyrate produced by intestinal flora has a strong anti-inflammatory effect and can inhibit inflammation in the colon and liver as well as the expression of inflammatory factors induced by lipopolysaccharides and NF-κB activation Perez et al.

Figure 5. Scatter plots for the causal association between several bacteria associated with butyrate-producing and sleep. Figure 6. The summary of the findings in our study and the existing knowledge in literature about different mechanisms that affect the sleep. Black indicated known evidence, bold orange italics indicated the findings by forward MR analysis, and bold blue italics indicated the findings by reverse MR analysis.

Metabolites of gut microbes such as short-chain fatty acids, butyrate and, acetate may also regulate circadian rhythms by influencing the expression of circadian clock genes Figure 6. Wang et al. have demonstrated that the gut microbiome modulates the expression of the circadian transcription factor NFIL 3 Wang et al.

Furthermore, the absence of gut microbiota and gut microbial metabolites such as butyrate and acetic can led to significant differential expression of hepatic and central circadian clock genes regardless of dietary changes Leone et al.

An observational study determined that short-chain fatty acids, propionate, and butyrate in feces were associated with nighttime sleep duration in infants Heath et al. Another observational study also found that changes in abundance of Lachnospira , Bacteroides , Faecalibacterium , and Blautia were significantly associated with sleep quality and disorders Li et al.

Yu et al. found that after giving mice oral high doses of gamma-aminobutyric acid fermented milk, the relative abundance of Ruminococcus , Allobaculum , and Adlercreutzia , and the levels of short-chain fatty acids increased significantly and sleep time was significantly prolonged Yu et al.

This result suggests that diet may affect sleep by regulating the intestinal microbiota. These previous studies and our research show that the gut microbiota and its metabolites can participate in the regulation of sleep. The relative abundance of gut microbiota is unique between individuals, and under healthy conditions, the gut microbiota displays resilience and stability.

Sleep disturbances or circadian rhythm disturbances have also been reported to disrupt the balance of the gut microbiota. Circadian rhythms are essential for maintaining normal physiological functions of the gastrointestinal tract, and circadian rhythm disorders are closely related to certain diseases of the digestive system Schernhammer et al.

In vitro experiments by Summa et al. proved that circadian rhythm disturbance and sleep fragmentation lead to the destruction of the integrity of intestinal barrier function, which in turn increased intestinal permeability Summa et al.

This increased intestinal permeability may lead to translocations of gut microbiota and its metabolites, which alters the variety and abundance of gut microbiota.

Poroyko et al. also demonstrated through in vitro experiments that sleep fragmentation can induce selective changes in intestinal flora, such as reducing the abundance of Bacteroidetes , Actinobacteria , and Bifidobacteriaceae Poroyko et al.

However, the disruption of the integrity of the intestinal barrier caused by sleep disorder may be related to its suppression of melatonin levels Gao et al. Gao et al. found that the decrease in the abundance of Faecalibacterium , Bacteroides , and Akkermansia caused by sleep deprivation was associated with decreased levels of melatonin Gao et al.

Consistent with these conclusions, we also found nominally causal effects of sleep disorder or sleep fragmentation on these bacterial taxa Figure 6. The previous studies mentioned above demonstrate that gut microbiota are involved in circadian rhythm regulation and show that circadian rhythm disturbances may cause changes in gut microbiota abundance by damaging the intestinal barrier or inducing changes in melatonin.

This is consistent with the results from 13 bacterial taxa found in our study that were both involved in and subject to sleep regulation, which suggests that regulation between gut microbiota and sleep may be bidirectional.

A major advantage of this study was that MR analysis effectively excluded the interference of reverse causation and possible confounding factors in inferring causal effects between gut microbiota and sleep-related traits. The SNPs of the intestinal microbiota came from the largest GWAS meta-analysis available, and the sample sizes were large enough to ensure the strength of the IVs and the robustness of the results.

The design of the two-sample MR further avoided bias resulting from overlapping data on exposure and outcome pools. Utilization of various statistical models such as IVW, weighted median, and maximum likelihood method as well as sensitivity analyses such as MR-PRESSO and MR-Egger regression intercept term tests ensured the confidence of causal effect estimates.

However, our study also had some limitations. First, genus level was the lowest classification level in the data for gut microbiota, which limited the ability to uncover causal relationships between gut microbes and sleep at the species level.

Third, the participants of gut microbiota and sleep in the GWAS meta-analysis were primarily of European ancestry. The same genetic variant may have different pleiotropic effects in different ethnic populations; therefore, the inference of causal effects derived in our study may not be applicable in non-European populations.

Fourth, in the reverse MR analysis, estimates of effects may have been biased by weak IVs because of the small sample size of the GWAS meta-analysis for sleep-related traits. Finally, we applied a number of exclusion criteria to select IVs; however, many internal and external factors affect gut microbes and sleep.

Thus, bias resulting from SNPs being associated with potential risk factors cannot be completely ruled out. In conclusion, this study represents the first bidirectional MR analysis to systematically reveal the causal association between gut microbiota and sleep.

Our findings suggest the possible causal effect of 42 bacterial genera on sleep-related traits. Conversely, sleep-related traits may also be involved in the regulation of the abundance of 39 bacterial genera.

In addition, 13 of these bacterial genera overlapped, which provides suggestive evidence for a reciprocal role between gut microbiota and sleep. The demonstration of a causal relationship between sleep and gut microbiota provides support for techniques to modify sleep by manipulating the gut microbiome.

However, the basic mechanism of gut microbiota on sleep is still unknown, and more research is needed to provide theoretical support for targeted intervention in sleep by regulating specific gut microbiota.

Publicly available datasets were analyzed in this study. DO and JW designed the research. JW, BZ, and SZ collected and analyzed the data and drafted the manuscript.

DO, XZ, and XL supervised the study. JW, ZH, and YX were involved in writing the manuscript. All authors contributed to the article and approved the submitted version. This work was supported by the National Natural Science Foundation of China NO.

The data analyzed in this study was provided by MiBioGen consortium and UK Biobank. We gratefully acknowledge their contributing studies and the participants in the corresponding studies without whom this effort would not be possible.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers.

Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

MR, Mendelian randomization; OR, Odds ratio; CI, Confidence interval; REM, Rapid eye movement; RCT, Randomized controlled trials; SNP, Single-nucleotide polymorphism; GWAS, Genome-wide association study; MR-PRESS, MR pleiotropy residual sum and outlier; IVW, Inverse-variance weighted; IV, Instrumental variables.

Belenguer, A. Two routes of metabolic cross-feeding between Bifidobacterium adolescentis and butyrate-producing anaerobes from the human gut. doi: PubMed Abstract CrossRef Full Text Google Scholar.

Benedict, C. Gut microbiota and glucometabolic alterations in response to recurrent partial sleep deprivation in normal-weight young individuals. Bowden, J. Mendelian randomization with invalid instruments: effect estimation and bias detection through egger regression.

Consistent estimation in Mendelian randomization with some invalid instruments using a weighted median estimator. Burgess, S. Mendelian randomization analysis with multiple genetic variants using summarized data.

Combining information on multiple instrumental variables in Mendelian randomization: comparison of allele score and summarized data methods. Celis-Morales, C. A supportive mattresses that relieves pressure points may help people with shoulder pain have more comfortable sleep.

Discover some of the best…. Medium-firm mattresses may improve sleep quality and align the body. Learn more about the best options for here. My podcast changed me Can 'biological race' explain disparities in health?

Why Parkinson's research is zooming in on the gut Tools General Health Drugs A-Z Health Hubs Health Tools Find a Doctor BMI Calculators and Charts Blood Pressure Chart: Ranges and Guide Breast Cancer: Self-Examination Guide Sleep Calculator Quizzes RA Myths vs Facts Type 2 Diabetes: Managing Blood Sugar Ankylosing Spondylitis Pain: Fact or Fiction Connect About Medical News Today Who We Are Our Editorial Process Content Integrity Conscious Language Newsletters Sign Up Follow Us.

Medical News Today. Health Conditions Health Products Discover Tools Connect. How gut microbes contribute to good sleep. By Jennifer Huizen on December 24, — Fact checked by Rita Ponce, Ph. The microbiota-gut-brain axis. Conducting the study. Study limitations and future research. Share this article.

Latest news Ovarian tissue freezing may help delay, and even prevent menopause. RSV vaccine errors in babies, pregnant people: Should you be worried? Scientists discover biological mechanism of hearing loss caused by loud noise — and find a way to prevent it. How gastric bypass surgery can help with type 2 diabetes remission.

Atlantic diet may help prevent metabolic syndrome. Related Coverage. Having social jet lag was associated with lower overall diet quality, higher intakes of sugar-sweetened beverages, and lower intakes of fruits and nuts, which may directly influence the abundance of specific microbiota in your gut.

These microbes are associated with poor diet quality, indicators of obesity and cardiometabolic health, and markers in your blood related to higher levels of inflammation and cardiovascular risk.

Sleep is a key pillar of health, and this research is particularly timely given the growing interest in circadian rhythms and the gut microbiome.

Even a minute difference in the mid-point of sleep can encourage microbiota species which have unfavourable associations with your health. Previous research has found social jetlag is associated with weight gain, chronic illness and mental fatigue. Professor of Nutritional Sciences.

Skip to main content Search news articles Search.