Jet Lag

What is jet lag?
Jetlag is caused by disruption of your “body clock” – a small cluster of brain cells that controls the timing of biological functions (circadian rhythms), including when you eat and sleep. The body clock is designed for a regular rhythm of daylight and darkness, so that it is thrown out of “sync” when it experiences daylight and darkness at the “wrong” times in a new time zone.

The symptoms of jet lag often persist for days while the internal body clock slowly adjusts to the new time zone. Jet lag has a high correlation with age … over 50 and you are more susceptible.

Tips for Jet Lag:

* Before you go: Make sure you have all your affairs, business and personal, in order. Ensure you are not stressed-out with excitement or worry, and not tired or hung over from a function the night before. Get plenty of exercise in the days before departure and try to avoid sickness such as the flu, colds, and so on. If you have a cold, flying will probably make it worse – ideally you should delay the trip. Start going to bed and getting up later if heading west, earlier if going east. Extend your period of exposure to light—in the morning or at night, depending on direction of travel and number of time zones you will cross.

* Drink plenty of water. The dry air in aircraft causes dehydration. Drinking plenty of nonalcoholic fluids counters this. Water is better than coffee, tea, and fruit juices. Alcohol is not only useless in combating dehydration, but has a markedly greater intoxicating effect when drunk in the rarefied atmosphere of an airliner than it does at ground level.

*Get as much exercise as you can. Walking up and down the aisle, standing for spells, and doing small twisting and stretching exercises in your seat all help to reduce discomfort, especially swelling of legs and feet. Get off the plane if possible at stopovers, and do some exercises or take a walk. Other hints, ideas .

*Timing of meals may play an important role in resetting body clocks, concludes a study that could aid scientists who are hunting for ways to combat travelers’ jet lag. The discovery, published in a recent edition of the journal Science, is in rats, not travelers, scientists cautioned. Still, “it’s noninvasive to change your eating habits”, notes lead researcher Michael Menaker, a University of Virginia biologist. “This would give you a reason to try it.”

Scientists discovered the brain-based clock is not the only control of circadian rhythms. Other organs seem to have their own clocks that supplement the brain’s master clock. Perhaps that is why sleep problems are not the only jet lag symptom; many sufferers complain of stomach upset and other problems, too. Menaker simulated jet lag by exposing rats to light six hours earlier than they would normally wake. While the light-sensitive brain clock could adjust in a few days, the rats’ separate liver circadian rhythms were out of sync for up to two weeks. The liver helps control food metabolism.

So Menaker, working with scientists in Norway and Japan, wondered if changing mealtimes would reset the liver’s own circadian rhythm and thus help readjust the overall body clock. Rats normally sleep during the day and feed at night. Allow them food only for four hours during daylight and they rapidly act like day is night, pumping away on their exercise wheels for a few hours before the food appears. Are they just hungry? By checking those liver genes under the microscope, Menaker found that the circadian clock in the liver had shifted by 10 hours after just two days of adjusted mealtimes.

This doesn’t mean eating habits are more important than light exposure for a person trying to prevent jet lag, Earnest cautioned, but that changing meal times might “be an added bonus” in helping to reset the body clock after a long trip. Indeed, “it is reasonable that … if you are going to Europe, you should a few days before departure, start eating dinner on European time,” Menaker said. “The brain will shift more quickly once you get there”, meaning the two organs might be in sync sooner, thanks to the liver’s head-start.

Note of caution: Some people use sleeping pills to try to alleviate jet lag. This is a dangerous approach as a report in the Lancet in 1988 says, “Estimated that over three years at Heathrow Airport, 18% of the 61 sudden deaths in long distance passengers were caused by clots in the lungs”. Sleeping pills induce a comatose state with little or no natural body movement. When blood does not circulate, there is a possibility that it will clot. In addition, many so-called sleeping pills are variants on antihistamines and they tend to dehydrate significantly adding to the already big problem of dehydration.