Jet lag

Jet lag is a condition which occurs when crossing several time zones due to travel. Our need for sleep and levels of alertness depend on something that happens in our bodies called the circadian cycle. The Circadian cycle determines the time of the day we feel awake or tired. It can be affected by events from the outside world and is also affected by daylight and darkness. When taking a long distance flight, you arrive in a new environment where the time of day might be different to the time of day your “body clock” thinks it is. This can make it difficult to adapt to the local time at your destination, which we call ‘jet lag’

Travellers usually find that they tolerate travelling west better than travelling east. This is due to the fact that our circadian cycle adapts faster when we are required to stay up longer to adjust to the local time. When travelling east, our circadian cycle tends to take longer to adapt, as it is more difficult to sleep earlier than it is to stay awake for longer. When travelling east, travellers tend to experience worse jet lag symptoms.

What are the symptoms of jet lag?

The risk of jet lag symptoms increases with the number of time zones you cross when flying. Travellers do not usually suffer from jet lag unless they cross at least three time zones. The more time zones you cross, the more noticeable the time difference will be.

The most common jet lag symptom is a disturbed sleeping cycle. You may find it difficult to sleep at night and stay awake during the daytime at your destination. As a result, you may feel lethargic, tired and have problems concentrating.

Other possible symptoms of jet lag include:

• digestion problems such as nausea, indigestion, diarrhoea and constipation
• changes in appetite
• confusion and light-headedness
• irritability and light-headedness
• feelings of disorientation and clumsiness
• memory problems
• increased sweating
• headaches
• sore muscles
• generally feeling unwell
• irregular periods (affect women who travel on a regular basis)

These symptoms should subside within 2 days. Depending on how many time zones you cross, they may remain for several days.

How can I overcome jet lag?

Although it is difficult to avoid jet lag entirely when travelling over long distances, there are steps you can take to overcome jet lag quicker. 

• Begin your journey well rested, after a good night’s sleep. 
• Start settling into the correct routine while you are still on the plane, by trying to sleep when it is nighttime at your destination. 
• Once you have arrived, you should try to adapt to the correct schedule as soon as possible.
• You can also take medication to help manage your symptoms to relieve jet lag faster.