While selfish mankind is focusing more and investing more in understanding internal circadian rhythms, we are utter foolish in recording every day disturbed circadian rhythms in outer environment. If someone notices, they are called climate hoax creators, conspiracy theorists etc.

“5 elements outside. 5 elements inside. No difference. If the outside is disturbed, such disturbances can occur on the inside too. The reverse also becomes true if done so deeply that we’re all the zombies who destroy everything for no good reason (okay, our current “good reason” is to make money) and will ultimately turn into cannibal zombies to end the feeding frenzy.” – Suraj Kumar

It is vicious cycle. You eat junk, disturb GUT bacteria and your circadian rhythms are disturbed (body clocks).

On the other hand, disturb rhythms by shift jobs, late night movies, parties, irregular life routine – all results into disturbed GUT.


Engineering an Internal Clock

Gut microbes affect circadian rhythms in mice, study says

A study including researchers from the U.S. Department of Energy’s Argonne National Laboratory and the University of Chicago found evidence that gut microbes affect circadian rhythms and metabolism in mice.

We know from studies on jet lag and night shifts that metabolism—how bodies use energy from food—is linked to the body’s circadian rhythms. These rhythms, regular daily fluctuations in mental and bodily functions, are communicated and carried out via signals sent from the brain and liver. Light and dark signals guide circadian rhythms, but it appears that microbes have a role to play as well.

All humans have a set of bacteria, viruses and fungi living in our guts, called the gut microbiome, which helps us digest food—and also interacts with the body in a number of other ways: there is evidence they affect allergies, mental health, weight and other metabolic conditions.

Researchers found that mice with a normal set of gut microbes showed evidence of a regular daily microbial cycle, with different species flourishing in different parts of the day and producing different compounds as a result. These compounds appear to act on the liver—they affected how circadian clock genes were expressed in the liver.

A high-fat diet reduced the variation in the microbial cycle; the circadian clock genes were disrupted, and the mice gained weight.

Meanwhile, “germ-free” mice raised without a normal gut microbiome showed evidence of a disrupted circadian clock cycle, but did not gain weight even on a high-fat diet.

The researchers hypothesize that high-fat diets change the compounds that microbes produce, thus disrupting the liver’s circadian clock signaling.

“The earlier explanation for microbiome-related weight gain was that some bacteria make calories from food more available to your body, but this is a fundamental alternative explanation,” said Jack Gilbert, an Argonne microbial ecologist who co-authored the study.


  1. Interesting, “germ-free” mice didn’t even gain weight on a high fat diet. From what I understand, it’s the high-fat diet that caused the circadian disruption as both “germ-free” and normal mice raised on a high fat diet showed circadian disruption. The reduced in microbiome diversity seems like a consequence of the high-fat diet.