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Fast Before a Long Flight
A lab study in the journal Science suggests that animals have a second biological clock that can reset their circadian rhythms, telling the body to shut down when food is scarce and wake up when it's plentiful again. Though it hasn't been demonstrated in humans, there's no reason to doubt that our biological clock works this way, too, says lead study author Clifford Saper, MD, PhD, department chair of neurology at Beth Israel Deaconess Medical Center in Boston. For an overnight flight to Europe, for example, you would stop eating after lunch, go to sleep when the plane takes off, then eat a hearty breakfast when you arrive the next morning to reset to your destination's time zone. Bon voyage!