The study by researchers at Nova Southeastern University (NSU) in the USA set out to investigate whether sleep quality could impact the health of the gut microbiome, which is all the microorganisms (bacteria, viruses, protozoa and fungi) and their genetic material found in your gastrointestinal tract. There has been growing interest recently in how the gut microbiome affects our health, particularly how the diversity of the microorganisms present there are linked to certain health conditions. Growing evidence suggests that the gut microbiome can also influence sleep quality.
For the new study, 26 male participants were asked to wear an Actiwatch for 30 days, a device which indicates the quality and duration of sleep measuring aspects such as bedtime, get up time, time in bed, total sleep time, sleep efficiency, and number of awakenings in the night. The researchers also tested the participants' gut microbiome.
The findings, published in the journal PLoS ONE, showed that increased sleep efficiency (the percentage of time spent asleep in bed) and total sleep time were positively associated with a more diverse gut microbiome, or in other words, a "better" gut microbiome.
"Based on previous reports, we think that poor sleep probably exerts a strong negative effect on gut health/microbiome diversity," said study author Jaime L. Tartar, PhD. "We know that sleep is pretty much the 'Swiss Army Knife of health," Tartar added. "Getting a good night's sleep can lead to improved health, and a lack of sleep can have detrimental effects. We've all seen the reports that show not getting proper sleep can lead to short term (stress, psychosocial issues) and long-term (cardiovascular disease, cancer) health problems. We know that the deepest stages of sleep is when the brain 'takes out the trash' since the brain and gut communicate with each other. Quality sleep impacts so many other facets of human health."
Tartar also noted that the diversity of the gut microbiome, or rather lack of diversity, has been linked with health conditions such as Parkinson's disease, autoimmune diseases, anxiety and depression. The more diverse someone's gut microbiome is, the likelier they are to have better overall health. Although genetics can play a role in the diversity of an individual's gut microbiome, as can certain medications such as antibiotics, so can diet. Eating food rich in prebiotics and probiotics, such as sauerkraut and yoghurt, may boost levels of beneficial bacteria in the gut.
Study author Robert Smith, PhD, said that understanding how sleep and the gut work may lead to a better understanding of the "two-way communication" between a person and their gut microbiome, and could lead to new ways to improve sleep. "The preliminary results are promising, but there's still more to learn. But eventually people may be able to take steps to manipulate their gut microbiome in order to help them get a good night's sleep."