[Question] Which is more difficult to adjust the jet lag when flying east or west?

Regardless of crossing 12 time zones eastward or westward, it takes about 9 days to adjust the time difference.

According to the report of Chinese Talk, taking an international flight will often disrupt the physiological clock of the human body because it spans multiple time zones in a short time. It sometimes takes longer than expected to adjust the jet lag. New research finds that passengers flying from west to east have difficulty adjusting the jet lag.

It is reported that a research report published by American experts in the journal Chaos on the 14th said that a new mathematical model takes into account how specific cells in the human brain react to cross time zones, which helps explain why flying east is more difficult to adjust jet lag than flying west.

Michelle Girvan, co-author of the research report and associate professor of physics at the University of Maryland, said that "neuron oscillator cells" coordinate with each other synchronously or connect with external signals to regulate the circadian rhythm of the human body, or physiological clock.

Gerwin said that these cells do not operate exactly in a 24-hour cycle, but slightly longer, about 24.5 hours. This means that the time of one day will be extended. For example, flying over several time zones from east to west is easier for the human body to adapt. She said it was easier to adjust the jet lag than flying from west to east.

In other words, flying east is more difficult to adjust jet lag than flying west, because flying west increases in the day and delays in the night, and the body has more time to adjust itself. On the contrary, it is more difficult to reverse jet lag when flying eastward with shorter days and earlier nights.

According to the study, the time needed to adapt to the new time zone depends not only on the number of time zones crossed, but also on the direction of passengers.

The researchers found that passengers crossing three time zones from east to west can fully adjust the time difference in less than four days. It takes about six days to cross six time zones, and nearly eight days to cross nine time zones. However, passengers crossing three time zones from west to east must spend more than four days to adjust the time difference. It takes more than eight days to cross six time zones, and more than 12 days to cross nine time zones.

Regardless of crossing 12 time zones eastward or westward, it will take about 9 days to adjust the time difference.

Due to jet lag, the physiological clock is confused, which will cause insomnia, low spirit, fatigue, poor appetite, indigestion and other symptoms, thus affecting people's quality of life.

Generally, the human body has a strong ability of self-regulation, so jet lag within 4 hours will not cause very obvious physiological reactions. But once the jet lag exceeds 6 hours, the physiological discomfort will become more obvious. The hardest thing is the time difference of 12 hours, that is, the day and night are just reversed.