New Research Shows Infant Gut Bacteria Has Its Own Circadian Rhythm

While there are numerous supplements marketed toward improved gut health, the bacteria in your gut, also called the gut microbiome, start to develop naturally in infancy. A new study from researchers in Germany suggests that some of these bacteria actually operate on a circadian rhythm, Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source   or sleep-wake cycle, that can affect infants’ long-term and short-term health, along with the babies’ own circadian rhythms. 

When a baby is born, their gut is sterile, Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source or close to it. The birthing process, aging, and food intake all help the development of a baby’s gut microbiome. The healthy bacteria present in the gut aid in the development of the immune system, the central nervous system, and digestion. Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source

The researchers performed a randomized trial with infants who were breastfed and others who consumed formula, comparing differences in gut microbiomes between the two. They found that while there were variations in bacteria between the two populations, age affected the development of gut bacteria rhythms more than diet.

During the first year of life, an infant gradually develops a sleep-wake cycle. Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source This partly explains why newborns have such irregular sleep patterns at first but slowly adapt to sleeping through the night as they grow.

Interestingly, the new study showed that particular bacteria within infants’ gut microbiomes have a circadian rhythm, becoming active and inactive with environmental factors like light exposure and feeding times. The researchers also noted that the circadian rhythms are bidirectional — the body’s internal clock helps regulate the sleep-wake cycle of the gut microbiome, and vice versa. 

The research team believes that the circadian nature of infants’ gut bacteria could affect disease development. Because there appears to be communication between an infant’s sleep-wake cycle and their gut bacteria’s sleep-wake cycle, outside factors like lack of natural light exposure or irregular feedings could hinder gut microbiome development and affect overall health.

The study acknowledged certain limitations, including a small sample size of 210 infants and restricted timing for stool sample collections. Additional research could help bolster the study’s findings and further explore the link between a person’s circadian rhythm and the 24-hour cycles present within gut bacteria.