Not eating may be the key to staving off jet lag

June 17, 2010

By Tabatha Elliott, PhD


If you’re a frequent long-distance traveler, then you’re all too familiar with jet lag. Nothing can ruin a good trip — or make a bad trip worse — than the miserable feeling of jet lag.

Researchers from Beth Israel Deaconess Medical Center in Boston discovered that humans have what is known as a food-related clock inside our bodies; and that this clock can supersede our body’s master clock, which is light-based and serves as our internal timekeeper. In other words, we have an internal clock that is in synch with the rising and setting of the sun, which is why you get so messed up when you travel and the sun suddenly rises and sets at a different time. In addition to light cues from the sun, our body clock also runs based on cues from when we eat. After all, we pretty much eat breakfast, lunch, dinner and all our other meals at approximately the same time of day.

The researchers reported that 16-24 hours of fasting, followed by refeeding, overrides the light cues your body gets and resets your body’s internal timekeeper. Of course, you’ll rarely want to fast, because it can lead to some muscle loss. But since jet lag can last for up to a week and mess up your training and eating (which can lead to even greater muscle loss), this is one of those times when we recommend fasting over the alternative.

If you’re traveling to a different time zone, try fasting for 16-24 hours, and then start eating again based on the new time zone.