Jet
lag is a modern disease because it is only with high-speed jet
flight that our bodies are able to cross several time zones
very rapidly. Everyone has, near the base of the brain, an area
of nervous tissue which is, effectively, a 24-hour clock, enabling
them to be awake and sleep appropriately. In another part of
the brain, a small gland, the pineal, during daylight, produces
the hormone, melatonin, a derivative of serotonin. The "clock" area of the brain is sensitive to melotonin and consequently the brain can tell whether it is day or night. In fast modern jet travel, this clock mechanism is thrown out of rhythm and jet lag results. It is usually worst when travelling from west to east. The symptoms include tiredness, insomnia, irritability and loss of appetite. Often, after a transatlantic trip, for example, it takes from 3 to 5 days to resolve. During this time concentration, work performance etc are at low ebb. Similar problems to jet lag can occur in shift workers and in old age, particularly if there is a degree of dementia, when the old person can suddenly develop complete day-night reversal and become severely confused.
The simplest way to deal with jet-lag, at the most sophisticated level, is to travel by Concorde and, if it is a short business trip, to try, as far as possible, to keep to the time habits of the country you have left. The vast majority are not in the position to do this. Usually there is little problem going from east to west, as from the U.K. to the U.S.A. The trip back takes more getting over. Sleep disturbance can be treated with conventional sleeping pills but these do not seem to alter the general symptoms of jet lag. Increasingly, melatonin by mouth is becoming a popular medication and seems to be very helpful in many cases in reducing the jet lag effects. Similarly it also seems to help shift workers and the elderly with sleep problems. |
