Air travel and jet lag

You’ve just got off an airplane and feel jet lagged. It can ruin your first couple of days of a beautiful holiday or even an important business trip. But what is jet lag and when and why does it occur?

Our systems have an internal clock too, often referred to as the circadian rhythm which also follows about a 24 hour schedule. It regulates our body processes and hormones and is set according to our external environment, chiefly sunlight and melatonin or the "hormone of darkness" that tells us when it’s bedtime and when to wake each morning.

When we travel across multiple time zones (by air, usually), our circadian cycles are out of sync with our environment. This can cause disturbances in our sleep and waking schedules, and can give us a stomach upset, fatigue through the day, and poor productivity at work. This syndrome is called jet lag.

Causes of jet lag: There are 24 time zones in the world, and the Greenwich meridian, UK, is the base. The idea is that for every 15° traveled, the time changes by one hour. This travel can be in either direction from the Greenwich meridian.

So, if you travel over three time zones, you are sure to experience jet lag. For instance, if you travel from the UK to Europe, Africa and the Middle East, you will not experience jet lag. But if you travel from UK or Europe to Asia, Australasia, the Pacific Islands, USA or South America, you will suffer from jet lag.

Symptoms: The symptoms of jet lag vary from person to person, and it also depends on how far you fly and how many time zones you cross. They include fatigue, feeling disoriented, irritability, lack of sleep, disturbed bowel schedule, dehydration, headaches, and dry skin.

How soon can you overcome it? If you fly east, jet lag becomes a big problem since your body has difficulty in adjusting to a shorter day. Generally for trips from west to east, you will need one day to recover for each time zone crossed, while for trips from the east to the west, you will need one day per one and a half time zones crossed. To avoid this feeling, people break up a long journey with a stopover which helps them adjust to the new time zone they are traveling to.

Counteracting jet lag:

Reset your watch when you board the plane so that the quicker you adapt to the new time zone the lower level of jet lag you are likely to suffer
In the new time zone, spend some time in the daytime as natural sunlight can help yu align your body clock
Adjust your bedtime and meals according to local time
Schedule any meetings when you are at the peak of your energy-either in the evenings if you’ve just flown east, or in the mornings if you’ve just flown west
Before and after a flight, reduce your alcohol intake
Exercise all you can by walking up and down the aisle, rotate your ankles and do gentle stretching exercises while still in your seat to banish all discomfort

So, take care when on a flight and plan to counteract the effects of jet lag.