Dr. Steven W. Lockley on the science of jet lag

Transcript

So when we learned to jet travel, when we invented jet travel, we also gave ourselves a new problem, which is jet lag. And we’ve evolved to shift by a few minutes a day in response to seasonal changes in light and dark, but we’re not very good at shifting large amounts every day. And so when we do those big flights across the planet, our body clocks can’t keep up, and we end up with the symptoms of jet lag, which is sleepiness, insomnia, and often other disorders of metabolism, eating and so on.

Now, the key time cue that our body clock uses to reset is the light and dark cycle. If we time light properly and time light avoidance or dark properly, we can shift the body clock much more quickly. So instead of shifting by up to an hour a day, which you would do if you just did it yourself and didn’t really know what you were doing, we can shift the body clock three times quicker than that, by about three or four hours a day, so we can get you much more quickly to that new time zone.