Managing Time Zone Changes – How to Best Adjust

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There is nothing worse than arriving at your destination feeling exhausted and unable to concentrate, particularly if you are scheduled to attend important meetings or events. Travelling long distances, and coping with multiple time zone changes can be difficult due to the normal physiological response to travelling long distances.

Time zone changes cause a disruption in normal circadian rhythms, which controls your sleep cycle.  The body clock which is situated in the hypothalamus, which is a part of the brain that controls body functions including sleep, hormone levels, blood pressure, body temperature, thirst and hunger.  Abrupt shifts in the light-dark cycle causes impaired daytime functioning, commonly known as jetlag.

The symptoms of jetlag can be influenced by the direction and timing of travel. Individual variability may also account for your ability to adapt to your new destination. Common symptoms of jetlag include daytime fatigue, sleep disturbance, reduced alertness, headache and gastrointestinal upset.  If you can, try to travel business or first class, as this will allow you to have sleep of better quality.


Try to adapt to the new time zones before you travel. Adjust the wake and sleep times to gradually bring you in line with the normal sleep- wake times for the destination.  When travelling eastward, this would involve having gradual earlier wake times (increase by 30-60 mins daily). This is easier than attempting to sleep at an earlier time.


Drink plenty of water and avoid high salt foods before and during your flight.  Dehydration can make your jet lag symptoms worse. Avoid alcohol and caffeine on your flight, and on the days before and after your flight. Both alcohol and caffeine lead to accelerated dehydration and result in poorer quality sleep, worsening the symptoms of jet lag.

Appropriate timed meals and composition

To accelerate realignment, gradually adjust meals to the new time schedule.  Eat small light meals on the flight. The composition of meals may affect circadian rhythms. There is some evidence that a program of high protein meals, and a period of fasting before arrival followed by a high-protein meal eaten at the appropriate time for breakfast at the end destination, may reduce the symptoms of jet lag.  Avoid rich foods, keep the quantities small and focus on light meals such as salads, fish and fresh fruits.


Light is the major signal that shifts the sleep-wake cycle. The timing of light exposure can help you adjust to your new time zone. When travelling west, expose yourself to light, and exercise late into the evening. When travelling east try and have a brisk morning walk. A new potential treatment using brief bursts of flashing light while sleeping has been shown in a small study to help people adjust to their new time zone and delay the onset of sleepiness by 2 hours. There are a few products on the market, and some have been used in athletes travelling long distances to help reduce symptoms of jetlag.


Melatonin helps to regulate the body’s sleep-wake cycle. It is a natural substance released from the pineal gland at night-time. A decline in melatonin alerts the body that night is ending.  It can be used to reset your body clock. Used in combination with light therapy, it may help to reduce the symptoms of jetlag.  It is best to take melatonin about an hour before bed. In Australia, your doctor must prescribe melatonin.

Jet lag is a normal physiological response to travelling across time zones. The body often requires a few days to adjust. Maximising your daylight exposure will help you restore your circadian rhythm and get back on track as quickly as possible.


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