January 30, 2023 – The gut microbiome appears to play a serious role in regulating body temperature, each for long-term health and in life-threatening medical situations corresponding to sepsis, in response to a University of Michigan study.
The research team examined data from patients hospitalized for sepsis and experiments with mice to find out the link between the gut microbiome – all of the microorganisms that live in our digestive system – and health outcomes, said a press release from the university.
Researchers examined rectal swabs from 116 patients admitted to the hospital and located that variation in gut bacteria correlated with temperature fluctuations experienced by patients during their hospital stay. In particular, they found that gut bacteria of the phylum Firmicutes were often related to increased fever.
“We know that temperature response plays an important role in sepsis because it plays a key role in determining who survives and who dies,” said university microbiologist and immunologist Robert Dickson within the press release. “But we don't know what causes this variation and whether it can be modified to help patients.”
The results were confirmed in controlled experiments with mice.
The gut microbiome may additionally be the explanation why human body temperature has dropped over the past 150 years, the press release states.
“Although we have not proven that changes in the microbiome explain the decline in human body temperature, we think this is a plausible hypothesis,” said Dr. Kale Bongers, lead writer of the study. “Human genetics have not changed significantly in the last 150 years, but changes in diet, hygiene and antibiotics have had profound effects on our gut bacteria.”
The American Journal of Respiratory and Critical Care Medicine Conclusion: “The gut microbiome is an important modulator of body temperature fluctuations in both healthy and critically ill states and therefore represents an important, under-explored target for modulating physiological heterogeneity in sepsis.”