It has become increasingly clear that gut bacteria play a big role in one’s health, potentially improving or damaging it depending on one’s diet and other factors. A new study out of Japan has linked gut bacteria to sleep quality, finding that people who have a messed up profile — such as from recent antibiotic use — may suffer from poor sleep as a result.
The study comes from the University of Tsukuba, where researchers studied the effects of antibiotics and gut bacteria changes on sleep using mice. One group of mice was dosed with strong antibiotics for a week in order to kill off their gut bacteria; a different control group of mice didn’t receive the antibiotics.
Of note, gut bacteria play an important role in breaking down food into metabolites, the profile of which was found to be significantly different in the mice given antibiotics compared to the control mice. Among other things, the mice were missing around 60 common metabolites.
By analyzing the metabolites and the role they play in the body, the researchers found that the antibiotics predominately impacted the processes involved in producing neurotransmitters. The mice given antibiotics were found to have low vitamin B6 levels, which play a role in the production of neurotransmitters, as well as high tryptophan levels.
Tryptophan is a precursor to the neurotransmitter serotonin, which — despite the high tryptophan levels — was found to be near zero in these mice. The findings indicate that antibiotics may trigger changes in the body that impair the tryptophan-to-serotonin pathway.
As part of the study, the scientists used EEGs to monitor the rodents’ brain activity, finding that the antibiotic mice got more sleep during what would typically be their active period of the day and less non-REM sleep during the hours they would typically sleep.
The study notes that the antibiotic-triggered changes that led to a lack of serotonin then spilled over to impacting sleep, resulting in trouble sleeping. The researchers suggest that changing one’s diet to alter one’s gut bacteria profile may trigger changes that help resolve sleep troubles — though, of course, that depends on the reason for poor sleep quality.