VOA健康报道2024--How to Prevent Jet Lag, Enjoy Travel

Many travelers face a common problem: jet lag.

It is the feeling of tiredness people get when traveling a long distance, resulting in a difference in daylight hours. Nobody wants to miss the fun because they are too tired to enjoy their vacation.

Here are some tips on how to deal with jet lag:

What is jet lag?

Scientists define jet lag as the effect on the human body of traveling across time zones. Sofia Axelrod studies circadian rhythms at Rockefeller University in New York. She said a circadian rhythm is like a biological clock programmed into almost every cell in the body.

"The clock is set by the 24-hour light and dark pattern," Axelrod said. "Every morning when we wake up, specialized¹ (light) receptor cells in our retina receive a daylight signal, which is transmitted to the brain and from there, (to) the whole body."

When we travel to another time zone, our eyes do not receive the daylight signal at the usual time. This causes our "internal clocks" to reset². But that process can take a while. During that period, we feel the effects of jet lag.

Is jet lag preventable?

People who travel long distances often want to prevent jet lag. One way has a high cost.

Malcolm von Schantz is a professor who specializes in circadian rhythms at Northumbria University in Newcastle, England. He said that paying a lot for a bigger seat and more space in an airplane can prevent sleep deprivation³.

He knows most people cannot pay so much to travel. But he said timing⁴ your flights can help. For example, he suggests flying from Europe to North America during the day, so that it is evening when passengers land and they can get to sleep.

"If you take the evening flight instead, you'll be woken up at midnight to be served breakfast and land an hour or two later, when both jet lag and sleep deprivation will hit you hard," he said.

Von Schantz also said flying in newer model passenger jets, like the Airbus A350 or Boeing 787 Dreamliner, might help. He said those planes can maintain a more comfortable atmosphere inside, causing less tiredness.

What should you do when you arrive?

Experts say being in sunlight is important to resetting⁵ your internal body clock. That could mean either avoiding morning sun or seeking it out, depending on where you started.

Getting light in the morning will move your body clock forward, while light exposure in the early evening will delay it. Sleeping for a short time during the day is acceptable, but scientists warn against sleeping for longer periods later in the day. Doing so might make it harder to sleep through the night.

Are there supplements or medicines for jet lag?

The brain naturally produces a chemical hormone⁶ called melatonin when the body thinks it is night. Taking melatonin as a supplement can be helpful. But it is not available everywhere and, in some countries like Britain and France, you need a doctor's permission.

Von Schantz said that one of the good effects of melatonin is that you can start taking it before you travel, to begin the process of resetting your internal clock.

"If you're in a part of the world where melatonin is available over the counter, you can combine the effects of light and melatonin to achieve the advance or delay (in your body clock) that you need," he said.

What can you do to deal with the effects of jet lag?

Russell Foster of Oxford⁷ University wrote a book on circadian rhythms. He said business travelers might want to consider arriving a day or two ahead of any important meetings or events. Being jet-lagged can lead to unwise decisions and unpleasant emotions.

Tourists might not need to think as clearly as business travelers, but they should still be careful, he said. He advises tourists to get enough sleep before doing anything that might be risky⁸ or that requires a lot of attention, like driving.

Foster said he tries to increase his exposure to light when he arrives at a new place to prevent jet lag. But he also has another method if light does not help: he drinks coffee.

Words in This Story

jet lag - n. a tired and unpleasant feeling that you sometimes get when you travel by airplane to a place that is far away

time zone - n. any one of the world's 24 divisions that has its own time

circadian rhythm - n. repeated activity in an organism that happens in 24-hour periods

pattern -n. a regular or repeated happening

retina - n. the sensitive tissue at the back of the eye that receives images and sends signals to the brain about what is seen

deprivation - n. the state of not having something that people need

comfortable -adj. to feel good and to not feel pain or discomfort⁹

hormone -n. a chemical produced by the body that influences how the body grows and develops

over the counter - expression. available for purchase without a special note (called a prescription) from a doctor

1 specialized   

adj.专门的，专业化的

参考例句：

• There are many specialized agencies in the United Nations.联合国有许多专门机构。
• These tools are very specialized.这些是专用工具。

2 reset   

v.重新安排，复位；n.重新放置；重放之物

参考例句：

• As soon as you arrive at your destination,step out of the aircraft and reset your wristwatch.你一到达目的地，就走出飞机并重新设置手表时间。
• He is recovering from an operation to reset his arm.他做了一个手臂复位手术，正在恢复。

3 deprivation   

n.匮乏；丧失；夺去，贫困

参考例句：

• Many studies make it clear that sleep deprivation is dangerous.多实验都证实了睡眠被剥夺是危险的。
• Missing the holiday was a great deprivation.错过假日是极大的损失。

4 timing   

n.时间安排，时间选择

参考例句：

• The timing of the meeting is not convenient.会议的时间安排不合适。
• The timing of our statement is very opportune.我们发表声明选择的时机很恰当。

5 resetting   

v.重新安放或安置( reset的现在分词 )；重拨（测量仪器指针）；为（考试、测试等）出一套新题；重新安置，将…恢复原位

参考例句：

• Range represents the maximum strain which can be recorded without resetting or replacing the strain gage. 量程表示无需重调或重装应变计就能记录到的最大应变。 来自辞典例句
• Adding weight to the puddle jumper by resetting its inertial dampeners. 通过调节飞船的惯性装置来增加重量。 来自电影对白

6 hormone   

n.荷尔蒙，激素，内分泌

参考例句：

• Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
• This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

7 Oxford   

n.牛津（英国城市）

参考例句：

• At present he has become a Professor of Chemistry at Oxford.他现在已是牛津大学的化学教授了。
• This is where the road to Oxford joins the road to London.这是去牛津的路与去伦敦的路的汇合处。

8 risky   

adj.有风险的，冒险的

参考例句：

• It may be risky but we will chance it anyhow.这可能有危险，但我们无论如何要冒一冒险。
• He is well aware how risky this investment is.他心里对这项投资的风险十分清楚。

9 discomfort   

n.不舒服，不安，难过，困难，不方便

参考例句：

• One has to bear a little discomfort while travelling.旅行中总要忍受一点不便。
• She turned red with discomfort when the teacher spoke.老师讲话时她不好意思地红着脸。