Coffee and naps not helping your jet lag? Try starving instead.

CHICAGO: Starving yourself before a long flight may help prevent jet lag, according to U.S. researchers.

Normally, the body's natural circadian clock in the brain dictates when to wake, eat and sleep, all in response to light. But it seems a second clock takes over when food is scarce, and manipulating this clock might help travelers adjust to new time zones, the researchers said Thursday.

"A period of fasting with no food at all for about 16 hours is enough to engage this new clock," said Dr. Clifford Saper of Harvard Medical School, whose study appears in the journal Science.

"Because the body's clock can only shift a small amount each day, it takes the average person about a week to adjust to the new time zone," Saper said in a statement. "And, by then, it's often time to come home."

Saper and colleagues knew that when food was scarce, animals were able to override their normal biological clock to improve their chances of finding food.

Studies have shown that mice fed only during the time when they normally sleep shift their body clocks to this new schedule.

"They would be awake and alert and ready to go an hour or two before a meal was due to appear to have maximal chance of getting the food," Saper said by telephone. "This is built into the brain. The problem is, nobody knew how it worked."

He and his colleagues set out to find this mechanism. They used a group of mice that had been genetically engineered to lack a master gene called BMAL1 that regulates the body's clock. They put this gene into the shell of a hollowed-out virus that acted as a vector to deliver the gene only to brain cells they were interested in studying.

When they put it into a small region of the hypothalamus that serves as the body's primary clock, the mice adjusted to a light-based schedule for waking and sleeping, but not eating.

"If you don't wake them up, they will starve to death," Saper said.

However, when they restored the gene only in a section of the hypothalamus that helps organize waking and feeding schedules, the mice adjusted to the eating schedule, but not daylight.

Saper said that these same clock genes were known to be in all mammals, including humans.

While skipping meals before a long flight or night shift has not been proven to work in humans, it may be worth a try.

"I'm certainly going to do it the next time I go to Japan," he said.

Contemporary art boom brings opportunities, and challenges, for insurers

More from Culture:

• Graffiti finds its place in contemporary art
• Younger Chinese artists struggle to excite buyers
• Contemporary art's "Old Masters of Tomorrow"

Search

Subscriptions
Sign Up  |  Manage