The gut microbiome, a lively community of microbes that resides in the digestive tract, seems to run on a 24-hour clock. That may be really important for our health — but scientists are just beginning to learn why. Early research hints that the bugs play a part in myriad bodily functions, from regulating sleep to breaking down drugs.
The researchers found that the microbes maintain these day-night rhythms even when they're extracted from the body and grown in the lab, suggesting that their rhythm is intrinsically regulated and thus not dictated solely by factors in the gut itself. It's unknown why gut microbes behave this way, but their cyclical behavior may somehow help them colonize the human intestine, the study authors theorize.
By submitting your information you agree to the Terms & Conditions and Privacy Policy and are aged 16 or over.The microbiome is beneficial to humans in many ways. For example, it helps protect us against infections by regulating the immune system and metabolizes parts of our food that we can't readily digest. The gut, in turn, provides microbes with a safe, warm place to live.
Sleep, disease and drugsSome past research has probed the circadian clocks of human gut bacteria, such as Klebsiella aerogenes and Bacillus subtilis. However, so far, most work in this field has focused on rodents' gut microbiomes. About 20% of microbes in the mouse gut are known to have a circadian rhythm, showing consistent fluctuations in their abundance at various points in the day.
Some findings in mice hint that byproducts made by bacteria in our own guts may influence our sleep-wake cycles. One called butyric acid is produced when bacteria digest dietary fiber and has been shown to promote sleep in mice. However, more evidence is needed to see if the findings actually translate to humans.
There's an emerging scientific discipline called chronopharmacology in which scientists are investigating whether the time you take a drug can affect its safety and effectiveness. In addition to influencing people's sleep-wake cycles, bacterial circadian rhythms might partly dictate how the body reacts to a given drug.