A new study found that jet lag alters the circadian rhythm of the human's gut microbes resulting to disruption in the metabolism that can make people fatter.
Researchers from the Weizmann Institute of Science spearheaded by Eran Elinav believe that their study is the first to explain how people with repetitive jet lag or shifting work schedules tend to gain additional weight. The findings of the study can be used to formulate deterrent treatments for people suffering from obesity due to these conditions.
The circadian rhythm or "internal body clock" is important in determining the sleeping patterns or the wake-sleep cycle every 24 hours, according to WebMD. However, there are factors that might disrupt the rhythm, such as shifting work schedules, pregnancy, time zone changes when traveling, medications and certain routine changes. When ignored, it can lead to different circadian rhythm disorder that includes jet lag or rapid time zone changes syndrome that is characterized by excessive sleepiness and difficulty of staying alert during daytime in people who travel across time zones.
The researchers tested their initial hypothesis by examining the fecal samples of humans and mice collected at different times of the day. The analysis showed fluctuations in the number of gut microbes and their activities depending on the times of the day.
As the study continued, the researchers exposed the mice to changing light-dark schedules and abnormal feeding habits for 24 hours. The team observed that the fluctuations stopped. The mice that were given fatty foods also gained weight and metabolic problems linked to diabetes. The two humans who were asked to travel from the United States to Israel also showed similar results.
"These findings provide an explanation for a long-standing and mysterious observation, namely that people with chronically disturbed day-night cycles due to repetitive jet lag or shift work have a tendency to develop obesity and other metabolic complications," said Elinav in a press release.
The study was published in the Oct. 16 issue of Cell.
