How unfair! The first day of your long anticipated vacation and this happens! You feel awful. It isn't influenza or an intestinal parasite. You haven't eaten tainted chicken or contracted Mad Cow Disease. The foreign allergens aren't to blame and you haven't developed a brain tumor from the headsets on the airplane.

So what is causing the fatigue, insomnia, stomachache, headache, bloating, distractibility, and irritability? And, more importantly, can you be cured or, better yet, have prevented the problem completely?

The cautious answer is 'maybe'.

Desynchronosis, or jet lag, is a temporary condition that most people experience following air travel across time zones. Risk factors include age, gender, and certain personality traits. The greater number of time zones crossed increases the amount of discomfort and the period of time required for recovery. Flights of similar duration but within the same or adjacent time zones don't cause the syndrome, though there might be other forms of distress.

Some of what is commonly blamed on jet lag is more likely attributable to the discomforts of airplane environment. Dry stale air, confined quarters, noise, vibration, unfamiliar foods and pathogens can be counteracted by opening the fresh air intakes, upgrading your seat when possible, moving about the cabin regularly, using earplugs, eating lightly, avoiding alcohol, and staying well-hydrated.

As opposed to the mostly annoying aspects of jet lag for the occasional traveler, female flight attendants and businesswomen face an increased risk of breast cancer, hormonal disturbances, and brain shrinkage associated with their frequent and prolonged flight hours.

In the past, US presidents, cabinet members, and upper-level business managers have insisted on maintaining their established routines, ignoring local time, and scheduling middle of the night meetings to the inconvenience to subordinates. This method works extremely well, but most people don't have the influence of elevated public office or the corporate weight needed to execute this egocentric solution.

What can the average flyer do?

Understanding circadian rhythms helps in managing recovery. Many of the body's functions vary depending on the time of day. 'Daytime' - or the period of greatest activity - is subjective to the local phases of sunlight and darkness, though studies have indicated that our cycles remain intact even when there are no clues regarding actual time. In such deprived or artificial environments, a group of people will unconsciously select  'daytime' and 'nighttime', preserving the length of the complete cycle at 23.7 to 25 hours long.

Air travel has shortened the journey to other 'daytimes'. The visual elements no longer synchronize with the innate ones and, thus, cause disharmony.

Techniques to avoid jet lag hinge on several factors, including number of time zones, direction of travel, length of visit, and existing personal sleep habits.

One of the solutions may involve varying visual exposure to sunshine, or artificial lights in the proper wavelengths during the first hours of arrival. For example: When traveling across six time zones from west to east (as in USA to Europe) avoid bright light between 430 A.M. and 930 A.M. on the first day. Then, go out into the sunlight for several hours. The second day, remain indoors from 130 A.M. until 630 A.M then seek out light until 930 A.M.

If headed west, six time zones, bask from 630 P.M. until 930 P.M then avoid bright lights for four hours. The next day, seek sunlight (or equivalent) from 930 P.M. until 1230 A.M. then avoid it until at least 430 A.M.

The schedule will vary with the number of time zones and a traveler's normal wake-up time. An online calculator is available at commercial sites such as The Body Clock - http://www.bodyclock.com/index.htm - along with artificial light products designed to help one achieve reliable exposure at the recommended times.

Light therapy is better described in 'The Complete Idiot's Guide to Getting a Good Night's Sleep' by Martin Moore-Ede.

Other methods employ programmable wristwatches that, by speeding up or slowing down, gradually adjust to the local time of the destination. This psychological technique claims to stimulate the brain's influence on internal cycles.

Herbalists sell a range of products designed to stimulate more rapid adjustment to the new time zone. These homeopathic remedies have only antidotal evidence to support the claims but also have few side effects, making them worth a trial run.

Aromatherapy at the destination may encourage relaxation and reduction of stress, alleviating part of the irritability. Splurging on a thorough massage may also induce sleep at the proper hour and decrease nighttime wakefulness.

From traditional medicine, a variety of sleep-aids and mild stimulants show promise. The new medications, Ambien and Restoril, are of short duration and, unlike previous remedies that left the user groggy upon waking, have minimal residual effects. Another pill, Modafinal, can promote alertness without further disrupting the already precarious sleep patterns of the traveler.

All these drugs require a physician's consent and prescription. Most doctors are reluctant to dispense drugs for symptoms endured by casual tourists because of the potential for abuse, but may be more willing for the business traveler's relatively greater need for immediate relief.

One businessman, a frequent long-distance flyer, describes his strategy:
 

I set my watch to destination time before I leave, sometimes as late as getting on the plane, and shift my activities to match those at my journey's end. I never calculate what hour it is at home.

At mealtimes there, I eat and don't allow the airline's service schedule to dictate mine. I'll refuse the meal, or ask that it be brought back later. I use melatonin tablets shortly before bedtime and have earplugs and blinkers to minimize distractions. I sleep when my watch indicates that night has fallen even if I need to take a sleeping-aid. I avoid alcohol and snacks but drink plenty of plain water.

If it is daytime upon arrival, I do not give in to the urge to nap. I walk instead, and expose my face to sunshine as much as possible. When arriving at night, I take an additional sleeping pill, if necessary, and set my alarm for the local morning. If I feel sleepy during the days that follow, I walk and seek out bright lights. Continuing this pattern eliminates my jet lag.
 

This traveler has found a combination of techniques that fulfill his needs.

Vacationers have a single advantage over their business counterparts, who must be at their best quickly. Napping is socially acceptable while on holiday and may nudge one toward adjustment.  If choosing to rest, experts advise setting an alarm for several hours, taking a warm shower for a quicker drop into slumber, and banishing guilt. After arising, engaging in light physical activities, appropriate for the local hour, will bump jet lag farther away by tricking the body into compliance with your surroundings.

Perhaps the best simple strategy for reducing the discomfort of long journeys is following the example set by the youngest. Children, especially those below the age of three, rarely experience the severity of symptoms that adults suffer. One of the reasons may be their plastic approach to life, which facilitates adaptation. They rest without apology, eat when hungry without glancing at the clock, and become easily immersed in the here-and-now.

Maybe adult worries and expectations contribute the biggest part of the perceived problems of travel. Scale back plans, ease into the activities, and remember there is no gold medal for seeing everything. It's a vacation - not an assignment.

There are many gadgets, remedies, and strategies for overcoming jet lag. The choice is an easy one.

Pick whatever works best for you.

References:

Sleep Disorder Channel: http://www.sleepdisorderchannel.net/jetlag/

No Jet Lag: http://www.nojetlag.com/jetlag1.html

Travel Advice at USA Today: http://www.usatoday.com/life/travel/business/2000/ltb082.html

Good Sleep: http://www.goodsleep.com

How to Avoid Jet Lag: http://www.asiatraveltips.com

Brain Shrinkage in Airline Travelers: http://news.bbc.co.uk/hi/english/health/newsid_1342000/1342081.stm

Breast Cancer Risks in Flight Attendants: http://news6.thdo.bbc.co.uk/hi/english/health/newsid_5F154000/154933.stm