JET lag can make frequent flyers fat, researchers have found.

    A study published in the journal Cell found that all living organisms, including bacteria in the body, have biological clocks that can get thrown out of sync by international travels.

    In humans, the result is jet lag. But at the microbial level, the result could be a gut full of the wrong kinds of bacteria — including species that promote obesity.

    Researchers looked at the microbiome, or bacterial populations, in rodent and human subjects. The abundance of different bacteria (and their activities) changed based on the time of day the sample was taken.

    Humans contain a whole host of fauna, known as the microbiome, the function of which is only partly understood. It is believed that one role of this ecosystem is in digestion.

    The researchers then messed with their subjects’ biological rhythm, flying two human subjects to Israel and manipulating the mice with lights and meals. When this was artificially disrupted by moving mice in the study to a different time zone, they fed more erratically, put on weight and developed metabolic problems associated with diabetes. The jet-lagged mice started putting on more weight than those that hadn’t “traveled,” even though they were on the same diet.

    When the researchers transferred gut bacteria from jet-lagged mice to healthy ones, the new mice saw the same effect. Humans were similarly affected: the two participants had an increase in bacteria that have been linked to obesity. But their microbiome normalized after only a couple of weeks. (SD-Agencies)