International Travel and Jet LagThe increase in long distance travel means that more people are experiencing the condition known as Jet Lag. Jet Lag is caused by flying across time zones in a short space of time. This causes the body’s ‘internal clock’ to fall out of sync with the present location. It may take some time – sometimes several days – before the body is able to adjust.

Jet Lag is now recognised as a Sleep Disorder and affects millions of travellers each year. It occurs when the body’s Biological Clock stays in its original time zone as it tries to adjust to the new location. Designed to sleep during darkness and stay awake during daylight the brain produces the hormone Melatonin that creates drowsiness. This is produced during the night and ‘switched off’ when daylight breaks. The body’s pattern of sleep and wake is controlled by this internal Body Clock.

A new location will require adjusting to different daylight hours, and other timetable changes such as mealtimes and leisure or business schedules.

Jet Lag (Desynchronosis) is different from other sleep disorders as it affects even those who normally sleep well. It is the result of crossing the earth’s meridians which define time zones. This means that the body has to acclimatise itself to the affect of new Circadian Rhythms which affect sleeping patterns.

Symptoms of Jet Lag

Travellers report a number of symptoms related to Jet Lag. Most report difficulty in sleeping and insomnia. Many suffer feelings of exhaustion or elation and difficulty in concentrating. Some find they are unable to function properly during routine tasks or while driving. Other symptoms include headaches, loss of appetite, mood changes and irritability.

Symptoms differ between individuals and some people are relatively unaffected. Usually travellers are able to adjust within a couple of days, but some report symptoms lasting up to a week. The number of time zones crossed may affect the severity of the condition.

All age groups are affected by Jet Lag, although the over 50s are more likely to suffer than the under 30’s. Conditions vary between individuals, but there is some evidence that those suffering from sleep deprivation may suffer more than those who sleep well before travel.

Some symptoms such as muscle aches and dry colds are more likely to be related to the flight itself and should not be confused with crossing time zones.

East to West and Back Again:

  • Symptoms are usually worse flying East making it difficulty getting to sleep. Flying West causes early morning waking.
  • If travelling West try to go to bed and wake up one hour later in the days before flying.
  • When travelling East, go to bed one hour earlier before travelling.
Helping Travellers Sleep:
  • Get plenty of sleep before flying.
  • Gradually adjust sleeping times to coincide with the destination before travelling.
  • Adjust eating and sleeping times on the flight in line with your destination.
  • Use natural stimulants such as coffee and exercise to help you adjust.
  • Avoid alcohol, coffee and heavy meals before bedtime.

Melatonin and Sleep

Melatonin is the hormone that helps regulate sleep. Although it is not available without prescription in this country, research has shown that it is effective in reducing some of the symptoms associated with Jet Lag. It is believed to be particularly effective when flying across several time zones and flying east.


Outdoor exercise on the day following a flight helps the body adjust to a new time zone.


Exposure to natural light or the use of a Light Box helps reduce the production of Melatonin. This will help reduce sleepiness during the day and speed up re-adjustment.


There is a report of acupressure helping relieve symptoms of Jet Lag. A group of Chinese acupuncturists tested the effectiveness of acupressure on themselves on flights between China and the USA. They discovered that when they used acupressure they experienced none of the symptoms of Jet Lag on arrival.

Adjusting Sleep

Travellers should try and avoid alcohol, caffeine and heavy exercise in the hours before bedtime. Earplugs and Sleep Masks may help acclimatisation. Learning how to relax will help you stay calm during travel, and increase your ability to relax and fall asleep at the right time.