The earth is divided into 24 time zones, with time changing by one hour for every 150 of travel east or west of the Greenwich meridian. When travelling from London to New York you would need to turn your watch back by five hours, while travel to Japan from London means turning your watch forward by nine hours (nine time zones). Arriving in Tokyo by plane from London at bedtime your body will feel as though it is lunchtime.
It takes about one day per time zone crossed to adjust to local time.
Ways of reducing Jet Lag
In order to cope with Jet lag you should get a good deal of sleep before your journey. It is also important to rest as much as possible during your flight. Planning to arrive at your destination as near to the time when you normally go to sleep will also help with the adjustment. If you are able to plan your itinerary allow time on arrival for adjustment.
Some people advise changing their watches to destination time when they get onto the plane. While this helps many people, for those who are on regular medication, such as diabetics, watches should remain on home time until you are able to adjust your medication to local times on arrival at your destination or as suggested by your health advisor.
On arrival at your destination get active as soon as possible and adjust your meals and activities to local time as soon as you can. Exposure to light is also a good way of naturally allowing your body to adjust. If you need to take a short nap – use an alarm clock or a helpful friend to wake you up!
Medication in reducing the effects of Jet-lag
For those with important schedules and meetings it would be worth discussing with your doctor the possible benefits of a mild sleeping tablet for 2-3 days whilst you adjust.
The drug melatonin is used frequently in the USA – although research is limited. Taking the drug is advised just before bedtime. After taking the drug you should avoid driving as it can make you very drowsy.
Note: This information is designed to complement and not replace the relationship that exists with your existing family doctor or travel health professional. Please discuss your travel health requirements with your regular family doctor or practice nurse.