Tips on Jet Lag
Most travelers have experienced jet lag. The common symptoms—insomnia, fatigue, change in appetite, irritability. After several days at your destination, your body's biological clock (circadian rhythm) becomes reset, and the symptoms subside. In general, it takes the body one day to adjust for each time zone crossed. On long haul flights it will take 2 weeks for all body functions to revert to normal.
Like many disorders that have no cure, there are lots of proposed jet lag remedies and preventatives. Numerous travelers have tried jet lag “diets.” More recently, exposure to artificial light sources and melatonin have been touted as being effective in resetting the body's clock.
Despite their apparent popularity, there is no scientific evidence that jet lag diets do any good.
Light exposure seems to play a role in resetting circadian rhythms. The mechanism involves suppression of the hormone melatonin, which is secreted by the brain's pineal gland.
The current dogma is that for eastward travel additional morning sunlight (whether cloudy or not) is beneficial, whereas for westward travel, afternoon light is important. Special high intensity lights (>10,000 lux) are available to help accomplish this end. Regardless of travel destination and arrival time, recent studies suggest that exposure to outdoor light at any time of day assists in readjustment of your circadian rhythm.
Placebo-controlled studies have shown that the hormone melatonin can reset your body's internal clock. In one study, travelers experienced much less fatigue, required less time to normalize their sleep patterns on melatonin. Some other studies, however, have shown no significant beneficial effect.
Adverse effects included headache and excessive drowsiness. In summary, melatonin appears to be somewhat beneficial, but there's much individual variation in response to this hormone. Concerns have been raised about melatonin's safety since the drug's strength, quality, and purity are not standardized. Also, there are little data on optimal dosing and timing of administration.
Since melatonin is a hormone, it is not recommended for children or during pregnancy. It should also be noted that unidentified chemical impurities have been detected in some melatonin preparations. For now melatonin is not recommended until further studies are done and a synthetic form approved.
Insomnia is one of the most troublesome symptoms of jet lag. While you're trying to fall asleep, your internal clock is saying “wake up.” The following sleeping aids are indicated and recommended:
- Sonata (zaleplon): Dose: 10 to 20 mg for adults
- Immovane: Dose 5 to 7.5 mg for adults
These medications have rapid onset, adequate duration of action, and minimum or no residual effect on daytime performance. Habituation is possible.
They should be used for only a short time and in the lowest effective dose.
Jet Lag Formulas "No Jet Lag"
These homeopathic preparations supposedly help reset your biorhythms. The evidence on their effectiveness is empirical and no scientific studies have been done. They are also expensive.
Jet Lag is Multifactorial
Feeling tired and irritable after a long trip is not due entirely to changes in your circadian rhythms. The issue is more complex.
For several days prior to departure, you are frantically taking care of what seems like a thousand and one last minute errands and details:
- You are probably too keyed up to get enough sleep.
- Your normal eating and drinking patterns are disrupted.
- You are somewhat apprehensive about flying.
- You are anxious about leaving home and/or your family.
- You fight heavy traffic getting to the airport.
- You park your car, but wonder if it will be safe.
- You carry a heavy suitcase half a mile to check in and hope it won't get lost.
- You catch a connecting flight.
- You stand in line again at check-in.
- You clear security checkpoints.
- Then you wait in a crowded, smoky airport lounge because your overseas flight is delayed by hours.
It's no surprise that you're feeling stressed out even before takeoff. Add to this a lack of sleep enroute, cramped seating, further dehydration—even constipation. Then, after arrival in a foreign country, you face still more hassles simply getting to your hotel. No wonder you've got jet lag.
Jet lag is not a single entity and the symptom complex will probably never be completely alleviated by a single treatment. The symptoms you experience are usually a combination of travel-related physical and emotional stress, sleep deprivation, plus the biological effect of your circadian rhythm being out of synch.
Reducing Jet Lag
- Don't drink too much alcohol—Alcohol is a depressant drug, and larger amounts can cause rebound nervous stimulation and restlessness, interfering with your sleep.
- Don't drink too much coffee—Excess caffeine may cause nervousness and insomnia heartburn. If you drink coffee at home have your coffee enroute at the destination time that corresponds to your regular “caffeine fix” time at home.
- Do drink water and fruit juices. They are good substitutes for (or complements to) alcoholic drinks and coffee. You may be somewhat dehydrated at the beginning of the flight due to disrupted eating and drinking habits prior to departure. Also, breathing low-humidity cabin air during a long flight will dry the mucous membranes of your throat and make you thirsty. Water and fruit juices are the best drinks to quench your thirst.
- Sleeping enroute when it coincides with nighttime at your destination.
- If you have an evening arrival, have a light dinner and go to bed late. The next day try to eat and sleep according to the local time.
- If you have a morning arrival, stay active during the day and get as much exposure to natural light as possible, if your schedule and the weather permit. If possible, don't nap, but overpowering fatigue should not be resisted. If you do nap, keep it under 45 minutes to avoid grogginess upon awakening.
- Take a sleeping pill if you have troubling insomnia (see below). Discontinue sleeping medication after three to five nights.
The Myth Of Dehydration
For many years it has been touted by the travel media that dry cabin air in jet airliners causes dehydration—which presumably could aggravate jet lag. The recommended remedy has always been to drink extra fluids enroute—and avoid certain beverages, such as caffeinated drinks, that would “dehydrate” you.
This advice appears to be misleading. According to a new study from the University of Nebraska Medical Center, healthy adults showed the same “hydration status” (as determined from urine analysis and other tests) when they drank caffeinated beverages, such as coffee or caffeinated colas as when they drank only water and/or fruit drinks. Lower cabin humidity causes, at most, only a 3 oz. water loss during an 8-hour trip. (In fact, the stress of travel may cause your body to retain water.) Compulsive drinking water or other fluids enroute is unnecessary and will lead to fluid retention and swelling.
If you are traveling on important business, you probably have more need than others to reduce the stress of traveling and symptoms of jet lag. Consider the following strategies:
- Avoid leaving large amounts of work that may be waiting for you on returning.
- Arrive one to two days before starting your business or making important business decisions.
- Reserve a sleeperette (reclining airline seat) or at least go business class, to improve the chances of sleeping enroute,
- Plan one or two extra days after arrival to rest and recuperate prior to business activities,
- Break up a long trip (>6 time zones) along the way for a day or two.
- Follow the general advice above.