Anyone who has flown across several time zones or been a shift worker knows just how unpleasant jet lag can be.
The reason is the way that kind of travel or working odd hours disrupts the body's circadian rhythms.
But researchers in California say they have discovered a molecule with the most potent effects ever seen on the body clock.
Dr Steve Kay from the University of California San Diego explained to the ABC what happens when the body clock is thrown askew.
"We have a very strong biological clock in our brain and that controls our sleep-wake cycle and our body temperature rhythms," he said.
"We have a very strong clock in our cardiovascular system that controls blood pressure. And we have a clock in our liver that controls all sorts of things associated with metabolism.
"In jet lag and shiftwork, what actually tends to happen is that these rhythms are no longer playing together as an orchestra and that's the basis really for why we feel so badly."
Dr Kay says dysfunctional body clocks can also contribute to cardiovascular disease, diabetes and some cancers.
However the ABC reports he and his colleagues think they may have found a way to reset the clock.
"We found a single chemical, a compound we call longdaysin, because it massively slows down the biological clock when it's applied to cells.
"And we were very encouraged to see the chemical also worked on different tissues we isolated from laboratory mice."
Dr Kay says longdaysin itself is only a research tool, but he hopes that in about 15 years it may be used in drugs to help people adjust to new time regimes.
The research into longdaysin is published in the online journal, Public Library of Science Biology.
