Long-haul flying can be debilitating. Dehydration, unfamiliar foods, cramped spaces, recycled air, lack of sleep, uncomfortable clothes, continual low-level noise, connections that disrupt sleep, and other factors all add to the misery of jet lag, and can even make you feel jet lagged when you're just a little beat up.

Jet lag is physical reaction to a rapid change in time zones. It affects most travelers, including seasoned fliers like flight attendants and pilots. Common symptoms include disorientation, irritability, fatigue, swollen limbs and eyes, headaches, cold-like symptoms, and irregular bowels.

On long flights, especially red-eye night flights, you can lose several hours of sleep time, which can set you back considerably even without the jarring time change. If you live by a regular schedule (up at 7, in bed by 10 every night), watch out. Jet lag hits those with rigid body clocks the hardest. For parents, be sure to bring along books and toys your child can play on his own, as kids are nearly immune to jet lag.

A general rule of thumb to keep in mind before any long trip is the 1:1 ratio: allow yourself one day to recover for every hour time difference you experience. So for Californians visiting the Big Apple, give yourself at least three days to fully adjust to the new time zone.

Before You Fly
Exercise, sleep well, stay hydrated, and stay sober. The worst thing you can do is get on a long-haul flight with a hangover. Some travelers like to exercise before they go to the airport. Try avoiding the escalators and moving sidewalks at the airport, and walk to your check-in area, and to your gate connections.

Adjust your habits before you leave. If you are traveling from the East to West Coast, you're facing a three-hour time change and you should try to adjust your internal clock. Three or four days before you leave, start to stay up a little later than usual, and sleep in a little longer. That way, if you become accustomed to falling asleep at 1 AM and waking up at 9 AM on the East Coast, it will be the same as falling asleep at 10 PM and waking up at 6 AM on the West Coast. Traveling west-to-east, do the opposite: get up and go to bed earlier.

Wearing two watches, one set to the current time, and one to the time at your destination, can help. Many business travelers use this tactic to stay in touch with what's happening back at the office.

During your Flight
Perhaps the most effective way to combat jet lag while in flight is to treat your body well. Stay hydrated by drinking plenty of nonalcoholic, non-caffeinated fluids. Bring your own bottled water so you're not dependent on flight service.

Get up out of your seat at regular intervals to walk and stretch. You can also do exercises like toe raises, isometric exercises, stomach crunches, and shoulder shrugs right in your seat. This keeps your blood flowing and prevents it from pooling at your extremities, a common phenomenon in pressurized cabins.

Other tips: Get up to wash your face, brush your teeth, or just stand up for several minutes. Wear loose-fitting clothing that breathes. Bring a neck pillow, blindfold or ear plugs-these work remarkably well, and are invaluable on red-eye flights. Also, avoid any footwear that is snug on your feet (high heels or wingtips); it is quite possible that your feet will swell in transit, making your post-flight trek to baggage claim a nightmare.

Medications & Vitamins
Melatonin is a chemical in the body that helps regulate sleep cycles. It can be taken in pill form. Many travelers swear by it for fighting jet lag. However, as popular as Melatonin is, it's controversial. Studies have indicated that incorrect melatonin usage can make you feel even more fatigued, so be sure to read all instructions before taking the product. For general information, try The National Sleep Foundation.

Magellan's offers a homeopathic remedy, aptly called  No-Jet-Lag It's a natural, homeopathic product that addresses all the symptoms of jet lag, not just sleeplessness, and it's made a lot of converts! The chewable tablets claim to attack all jet lag symptoms, and come with a money-back guarantee.. Made in New Zealand

Some travelers use sleeping pills, antihistamines and motion sickness pills to induce sleep on planes, at hotels, in airports, and on layovers. While they work for some, others are left feeling miserably groggy. Consult your doctor before taking any medication.

If all else fails, try an alternate therapy. Light therapy has become a popular treatment for jet lag, and it makes sense. At its heart, jet lag means you're out of step with the rising and setting of the sun. Unfortunately, the jury's still out on this one. Debate centers on precisely what kind of light is best -- natural, artificial, bright or dim. Some researchers and enthusiasts recommend simply spending 15-20 minutes in direct sunlight without sunglasses as soon as possible after landing.

An interesting resource for light therapy comes from Outside In, a commercial light therapy outfit: The Jet Lag Calculator - Reset Your Bodyclock. If you have success with this method, let us know on the boards.

The Jet Lag Diet
The so-called "jet lag diet," an alternation of feasting and fasting for three days leading up to a longhaul flight, was very popular a few years back. The military tested the diet, concluding, basically, that it is bunk. Nonetheless, Ronald and Nancy Reagan used it during their White House days, and some travelers still do. If you'd like to try it out for yourself, check out the diet regimen.

Eating foods that are easy to digest is always a good way to go. Foods that are relatively high in fiber, and foods that are not too rich, are often the gentlest on your belly. Fats tend to keep you awake, while carbohydrates usually put you to sleep. If you need to stay awake for a stretch to help you get on local time, eat peanuts, eggs, meats, and other high-protein or fatty foods. If you need to fall asleep, eat carbohydrates, such as pasta and breads.

Caffeine is also useful if you need to stay awake. However, we don't recommend that you drink so much coffee that your stomach feels like it's under siege. Also remember not to go overboard. While it might seem tempting to guzzle several cups of coffee when your eyelids begin to droop, you could end up wide awake at 1 AM. Be sure to use all dietary changes in moderation.