Jet lag brings the bowels out of rhythm

Jet lag and shift work remove intestinal flora from the rhythm

17/10/2014

Usually people are awake during the day and sleep at night. The same applies to the bacteria of the intestinal flora. However, if this rhythm gets out of step, health effects such as metabolic diseases and obesity can result, say Israeli scientists in the journal "Cell".

„These findings provide an explanation for a long-term and mysterious observation that humans, whose day-night rhythm is disturbed by jet lag or shift work, tend to develop obesity and other metabolic disorders“, said Eran Elinav from the Weizmann Institute of Science „Cell Press“. Your latest research could contribute to the development of new drugs or treatment: „These surprising findings could enable us to develop preventive treatments to lower the risk of the disease to these people“, Elinav continues.

The fact that disturbances of the day-night-rhythm or the change of light and dark, as they occur among shift workers or travelers between the time zones, can cause cardiovascular diseases, obesity or diabetes, was already well-known among medical professionals. The reasons for this, however, were so far unclear.

In their study, the scientists used mice to study how the bacterial composition changed during the day, and found that the bacteria fluctuated both in frequency and in type. In addition, the function of the intestinal flora changed with the time of day.

Also in humans rhythmic fluctuations in the intestine
The bacteria of the intestinal flora are not only influenced by the light-dark change, but also the time of food intake plays a role. When both feeding time and light-dark changes were changed, the intestinal flora changed such that the test mice developed a precursor to diabetes and obesity in a fatty diet, which was not the case in non-jet lag control animals. However, when these animals were given bacteria from the jetlag mice, the control animals showed the same symptoms as the jet lag mice.

The same thing happened when the researchers transferred intestinal bacteria from people with jet lag to germ-free mice. The animals rapidly increased and formed the pre-diabetes stage. Thus, the Israeli researchers have provided evidence on the relationships of jet lag and changes in the intestinal flora.

Preliminary results
However, their research results are not considered to be conclusive, said researchers from the Weizmann Institute. However, these would suggest a connection between jet lag, changes in the intestinal flora and the formation of metabolic diseases in humans and thus explain the frequent occurrence of diseases among shiftworkers and frequent flyers. The treatment may be targeted for probiotic or antimicrobial therapy, the researchers write. „Our results show a new therapeutic target that could be used in future studies to normalize the intestinal flora of people such as shift workers and frequent flyers whose lifestyle has frequent changes in the sleep pattern“, Elinav in Cell Press. „The aim is to reduce the harmful changes in the intestinal flora with probiotic or antimicrobial therapies or even to prevent the risk of obesity and its consequences.“ (Jp)