The expression ‘jet lag‘ is one that is given to a range of different symptoms that can be experienced by people who fly to a new time zone, and then have to adapt to a different schedule of daylight and darkness. Jet lag can affect any travellers of any age, and is a consequence of the internal body clock being unable to adjust to the new time zone straight away. Jet lag can cause sleep difficulties, and can result in feelings of drowsiness and tiredness during the daytime, and can sometimes cause problems with digestion.
There are a total of 24 different time zones in the world, and the human body has a natural internal clock controlling 24 hour circadian rhythms. Crossing time zones quickly, being an activity that we have not evolved to cope with, can disrupt these rhythms. The body clock influences the pattern of waking and sleeping, in addition to circadian rhythms in relation to:
- Production of urine
- Blood pressure
- Bowel habits
- Body temperature
Social interaction and light eventually set your body clock to your local time, but after travelling across time zones the body clock can take a while to adjust.
Different people can often experience different symptoms as a result of jet lag and the severity of it can also differ based upon the number of time zones that are crossed. There should be little jet lag caused by a shorter flight across just a couple of time zones, and the great majority of people only experience symptoms after having crossed at least three time zones. Treatment for jet lag is available from The Online Clinic .
Probably the most common symptom of jet lag is a disturbed sleep pattern which makes it difficult to fall asleep at the normal time, often resulting in sleeping during the day and being wide awake at night. Other symptoms that can be experienced by people suffering from jet lag include:
- Concentration problems
- Difficulties with memory
- Lack of energy
- Irregular periods for frequent female travellers
- Loss of appetite
- Feeling lightheaded
- Sore muscles
- General feeling of ill health
For people who have flown across nine time zones or more, especially in an easterly direction, symptoms can last for up to six days. Symptoms tend to be more severe for those travelling east; it’s possible that adapting to a longer day is easier for the human body than adapting to a shorter one. It is far more difficult to try to force sleep when the body is not ready for it, than it is to stay awake for a couple of extra hours.
There are a number of things that can be done to cut down on the effects of jet lag, and frequent flyers should be particularly au fait with these methods. One good tip is to set up a new routine and attempt to stick to it as quickly as possible, including sleeping and eating at the appropriate moments in your new time zone.
Even after a long and tiring flight, it is a good idea to try and remain active until the it’s the right time (in your new time zone) to fall asleep. You should also try to spend plenty of time outdoors, as natural light helps the body to adjust to the new routine.
Some people use sleeping pills to relieve the sleeping problems that can result from jet lag, but they are not recommended, due to side effects such as headaches and diarrhoea, and the risk of developing a dependency on them.
Although it is not possible to completely prevent jet lag, there are ways to limit its effects, which should be of particular interest to frequent flyers. One good tip is to make sure you have had enough sleep prior to travelling, as jet lag can be made much worse when you already feel tired. It may also be a good idea to try to alter your sleeping routine several days prior to departure.
During the flight you should take short naps and drink plenty of water, while avoiding alcohol and limiting your consumption of caffeine. Staying active, and immediately altering your watch to reflect your new time zone are also good tips.