App could cut jet lag short

Shaking off jet lag could be as easy as downloading an app. Researchers developed the iPhone app, called Entrain, using mathematical analyses of humans’ daily rhythms to calculate the quickest way to adjust to new time zones.

Users plug in their destination and arrival time, and Entrain advises times of the day to soak up or stay out of the light. The schedules are surprisingly simple, says mathematical biologist Daniel Forger, of the University of Michigan in Ann Arbor.

“They might say, ‘Hey you should keep the lights on in your room until midnight,’” he says. “Or ‘you should stay in darkness until 10 a.m.’”

Scientists have previously created mathematical equations that describe how humans’ internal clocks respond to light, Forger says.

He and a colleague used a computer program to solve the tricky problem of finding the best lighting schedules for more than 1,000 possible trips. To do so, the researchers asked a question: If a traveler wants to move their body’s clock from New York to London time, for instance, what lighting schedule gets them there fastest?

The pair reports the results April 10 in PLOS Computational Biology.