Jet lag often strikes airline passengers who are moving between time zones, not within the same time zone. A flight leaving Chicago at 1pm local time, for example, may land roughly at 1pm local time in California. The passengers would still be adjusted to Chicago time, however, so they might experience symptoms of jet lag as their sleep cycle becomes disrupted. The light cues of a California sun may also cause Chicago passengers to feel disoriented or confused at their normal bedtimes.
The symptoms of jet lag can go beyond a temporary confusion or disorientation, however. Some passengers who have traveled across several time zones may experience severe headaches, sinus congestion, general irritability, and even mild depression. The disruption to the passenger's Circadian rhythm may linger for several days, and can be even worse for those who travel from west to east. Gaining several hours of daylight does not appear to be as debilitating as losing hours from a natural bedtime after dark.
Some suggested remedies for jet lag include moderate exercise, maintaining normal eating schedules regardless of local time, and getting sufficient amounts of sleep. Some seasoned air travelers also suggest removing shoes and socks in order for a passenger to rub his or her bare feet on the plane's carpeting. The familiar sensation should help passengers orient themselves after a long flight with few natural cues. Anti-nausea medications for motion sickness may also have some positive effects on feelings of jet lag as well.
The main, but not the only cause of jet lag is crossing time zones. Usually going east is worse than going west. Children under three don't seem to suffer jet lag as badly, as they are more adaptive and less set in their ways. Adults who adjust readily to changes of routine also seem less susceptible to jet lag. Those who are used to a fixed daily routine are often the worst sufferers.
If you're over-tired, excited, stressed, nervous, or hungover before the flight, you are setting yourself up for a good dose of jet lag. How many times have you heard travelers say "Don't worry, I'll catch up on the flight"? Well you don't. The wise traveller who wants to get the most out of a trip has a good night's sleep prior to departure.
The air aboard passenger jet aircraft is dry. To people who normally live in more humid conditions the change can be striking. The dryness can cause headaches, dry skin and dry nasal and throat membranes, creating the conditions for catching colds, coughs, sore throats or the flu. Drinking plenty of water helps, and some frequent flyers take a bottle of water with them. Some airlines supply water frequently to passengers, but others only have a small water fountain near the toilets. Coffee, tea, alcoholic drinks and fruit juices are not recommended. Water is what your body wants.
At a cruising altitude of near 30,000' the aircraft is pressurized to near 8,000'. Unless you live near 8,000' and are acclimatized to this pressure you may suffer from swelling, tiredness and lethargy.
Providing a constant supply of fresh air in the cabin costs the airlines money. A lack of good air helps make you tired and irritable and can cause headaches. Sometimes if you ask the flight attendants to turn up the fresh air they will do so.
The impact of alcohol on the body is 2-3 times more potent when you're flying. One glass of wine in-flight has the effect of 2-3 glasses on the ground. Add this to the other problems mentioned here, and you can get off the plane with a huge hangover that simply compounds the effects of jet lag.
Airline coffee and tea not only tend to taste awful - they have a higher than usual caffeine content and are abrasive on the stomach. Orange juice is also abrasive if you are not used to it. If you don't normally drink strong coffee, tea or orange juice, don't try it while flying. Also go easy on the frequent meals served in-flight. You don't need them. And sitting in a cramped position puts extra pressure on your stomach. Also beware risky foods served on some airlines in certain parts of the world, including salads and cold meat and fish. According to WHO, 50% of international travellers get stomach problems, so dietary care is important while flying.
Lack of exercise is one of the worst aspects of long haul flying. It makes the flight uncomfortable and sets you up for a longer period of jet lag afterwards. Do stretching exercises in your seat, especially for the legs, and if possible go for walks up and down the aisle. If you have a spare seat next to you, try to get your feet up. Get off the plane whenever possible at stopovers and do some exercises (don't worry what others think). If there is an opportunity during a ground stop, take a shower - it freshens you, tones the muscles and gets the blood moving again.
The symptoms of jet lag can vary from person to person. The severity of your symptoms will usually depend on how far you have travelled and how many time zones you have crossed. Most people will only have the symptoms of jet lag after crossing at least three time zones, although some people may get mild symptoms after shorter journeys.
A disturbed sleep pattern is one of the most common symptoms of jet lag. Although jet lag can make you tired, you may find it difficult to sleep at the correct times. For example, you may be awake during the night and sleep during the day.
As well as disturbed sleep, other symptoms of jet lag can include:
indigestion
constipation
diarrhoea
nausea
loss of appetite
difficulty concentrating
feeling disoriented
anxiety
irritability
memory problems
clumsiness
lack of energy
lightheadedness
confusion
headaches
sweating
muscle soreness
menstrual irregularities in women who travel often
generally feeling unwell
The symptoms of jet lag will usually last for no more than a day or two, depending on how quickly your body can adjust to the new time zone.
If you have ever flown across a few time zones, you are undoubtedly familiar with the struggles of adjusting your sleep to the new hours -- jet lag. Why is jet lag so hard to tolerate? Is there anything that can be done about it?
First, it should be recognized that your body wishes to keep a regular sleep schedule, as is reflected in sleep hygiene guidelines. Certainly we are creatures of habit, and our bodies like when we go to bed and get up at the same time every day. Our biological clock, which is controlled by part of the brain called the suprachiasmatic nucleus, helps us to keep a regular schedule by releasing hormones on a regular pattern. This pattern is called a circadian -- or near-day -- rhythm. Our sleep follows this same regular pattern.
When we disrupt the regularity of these cycles, our body treats us unkindly by making us sleepy or alert when we don’t wish to be. We may also have difficulty thinking, an upset stomach, a headache, or even mild mood changes. It is no wonder that we have trouble sleeping when we travel. For example, if you were to go to bed three hours early tonight, you would have great difficulty falling asleep. However, if you fly from California to New York and crawl into bed at your normal bedtime, you are effectively attempting the same thing (considering the time zone change).
How can we counter our circadian rhythm when we travel? One solution would be to keep the same sleep/wake hours as our original time zone, going to bed and getting up based on the times at home. This may not be the best way to enjoy our travels, especially if we fly great distances. An alternative would be to slowly adapt to the new time zone prior to leaving.
We can conquer jet lag by adjusting our sleep by an hour for a week at a time. If we are crossing two time zones, the change can occur over two weeks. If traveling west, we would go to bed and get up an hour later for one full week. During the second week we would repeat the same, going to bed and getting up another hour later. If traveling east, we would go to bed and get up an hour earlier each week. If we can slowly adapt to the change, we will tolerate it better. Unfortunately, unless the trip is quite lengthy, we wouldn’t be able to adjust the other way for our return home.
Another alternative is the use of melatonin. Melatonin is a naturally occurring hormone in our body that follows a circadian pattern. It is often called a “sleep hormone” because it peaks during the night, but it only induces sleep at high doses. It can, however, cue our body to adjust our naturally occurring circadian rhythm. By taking a melatonin pill a few hours before our desired bedtime, we will more likely be able to sleep. If we find ourselves waking too early, melatonin in the early morning hours will help us sleep in.
The use of a light box can also shift our circadian rhythms when we travel. Imagine it pushing back your desire to sleep. If you are sleepy too early, use the light box at night to put off bedtime. If you are sleeping too late into the morning, use it when you get up to alert your body and mind.
Any of these solutions will help you to adjust your sleep schedule to a new time zone, and make your travels from home the joy that they should be.