If you've ever been on long haul flight you'll know jet lag can just make you feel tired, but did you know it might also make you put on weight?
Scientists from Israel discovered the circadian rhythm of organisms that live in our gut is disrupted when we travel through time zones.
The researchers found that this disruption changed the function of the metabolism in mice, and therefore could cause weight gain in humans, also.
During the study, published in the journal Cell, mice gained more weight when fed fatty food after suffering from jet lag.
The researchers also found that the composition of gut microbes in two humans who travelled from the United States to Israel changed to favour the growth of bacteria that can lead to metabolic disease.
Metabolic problems due to disrupted body clock have previously been linked to shift workers having a higher risk of diabetes.
Speaking on the latest findings, Eran Elinav of the Weizmann Institute of Science told The Telegraph: "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.
"These surprising findings may enable us to devise preventive treatments for these people to lower their risk for these complications."
Long plane journeys also disrupt our sleep pattern. Previous research has shown lack of sleep can increase hormones that increase a person's appetite - potentially another reason why regular flyers gain extra pounds.
SEE ALSO:
Shift Workers At Higher Risk Of Developing Diabetes, Study Finds
Suffering From Jet Lag? Scientists Step Closer To Helping Body Clock Adjust To Time Zones
