New Research Reveals More About the Gut Microbiome’s Role in Regulating the Circadian Rhythm and Metabolism

By Kate Anastas
Friday, September 10, 2021
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Focusing on maintaining healthy gut microbiota may help patients avoid future health problems, such as obesity, diabetes or fatty liver disease.

The central clock, the brain’s suprachiasmatic nucleus, is not the body’s only internal mechanism for controlling circadian rhythms. Researchers such as Eugene B. Chang, MD, Professor of Medicine and Director of the Microbiome Medicine Program the University of Chicago, and his colleagues suspect the gut microbiome translates dietary cues to the body’s circadian clocks that help regulate energy balance.

In a recent study published in Nature Reviews Gastroenterology & Hepatology, the researchers took a close look at how oscillators in the gut, “microbial oscillators,” act as drivers of the circadian rhythm, as well as regulate the metabolism. By ameliorating disruptions to circadian rhythms, scientists believe people can avoid certain diseases, including obesity, fatty liver disease and diabetes. However, there was a major factor that hindered this process: the Western diet.

“Diet plays a role in the microbes you have and what they are doing,” Dr. Chang says. “We’ve found that the Western diet completely disrupts and changes the gut microbiome. Microbial oscillators disappear with a high-fat, high-calorie, low-fiber diet. Low-fat diets promoted more ‘oscillations’ of certain microbial populations.”

Applications in Clinical Practice

While further research is needed to better understand the influence of microbial oscillators on a host’s metabolism and circadian rhythms, studies like this help physicians better understand how to promote microbiome-based interventions for maintaining health and countering metabolic disorders. Clinical implications include:

  • High-fat diets may do more harm than good. Dr. Chang warns against going too extreme, instead suggesting healthcare providers promote a diverse, balanced diet in which a person moderates fat and carbohydrate levels for a healthier circadian and metabolic state.
  • Probiotics may not be enough to replace microbial oscillators because of the way they pass through the gut. Instead, Dr. Chang encourages focus on restoring oscillators in a way that is compatible with the GI tract and that will graft, and then addressing when patients eat, what they eat and how much they eat to maintain a stable relationship with microbial oscillators.
  • Time-restricted diets, such as intermittent fasting, may have some merit because of the alternating eating and fasting periods.

“The gut microbiome is an organ ... just like our liver or heart; we need to think of it that way,” Dr. Chang says, challenging conventional definitions. “Then we can ... develop metrics to assess when the gut microbiome is healthy or not, and know precisely how to rebalance, correct or rebuild the microbiome.”