Modify your schedule One way to cope is to start adjusting even before you arrive in a foreign country. If you know that Paris is six time zones away, try going to sleep and waking up a few hours earlier each day (for instance, if your bedtime is usually 11 p.m., make it 9 p.m.) This way, the time difference won't be so shocking. Most people aren't this prepared, or their work and school schedules won't allow them to change their sleep patterns. Some people cheat by staying up all night before they board a plane. This can work, but it's still tinkering with your circadian rhythm. Plus, given the stresses of air travel, less experienced fliers might do better to get a good night's sleep; it can be advantageous to feel bright-eyed and well-rested before approaching the security checkpoint. Ideally, you should aim to sleep on the plane. Despite the movies and in-flight magazines, there isn't much to do onboard except sit in your seat and wait for the aircraft to land. This way, you'll feel relaxed when you arrive—alert enough to hail a cab and check into a hotel (usually your top priorities). Avoid caffeine and alcohol The modern airport is more than a few landing strips and a bag-check counter: It's also a mini-mall where travelers can buy gifts, luggage, newspapers in any language—and booze. While many travelers look forward to the airport bar, where a cocktail and some harmless flirting can break up the airport's tedium, alcohol may worsen your jet lag. The same goes for coffee, some teas and soft drinks, nicotine—anything that affects your mood or sleep patterns. If you're seeking a beverage, juice and water are the most prudent choices, not only because they're decaffeinated, but because the dry air inside an aircraft's cabin can be withering. Prepare your body for time-zone changes by staying hydrated and clear-headed. Go west, young friend Any business traveler will tell you: It's much easier, in general, to travel west. For example, if you travel from New York to Paris (six times zones away), you're losing six hours of your day. You might leave JFK airport at 8 p.m., and the flight is seven hours long, but when you arrive at Charles De Gaulle, it's now 13 hours later (or 9 a.m.). You've lost much of your night, and even if you took advantage of the complimentary pillow, you still enjoyed a maximum of only seven hours of sleep. But if you take the same flight, at the same time, from Paris, you'll arrive in New York only one hour later (you left at 8 p.m. and arrived at 9 p.m.), which means you can take a taxi to your hotel and indulge in a full night's rest. No matter what your circadian rhythm is, a solid eight hours of sleep generally is helpful. Surprisingly, this even works for Americans traveling to Asia. You may cross the International Date Line (IDL), but you won't feel that you're losing much time (for instance, you leave Seattle at 12:30 p.m. and arrive in Tokyo at 4 p.m.). The only tricky part is that you're arriving in Tokyo the next day, even though the clock says it's only a few hours later. For first-time travelers to Asia, crossing the IDL can be alarming (essentially, you're losing a full day), but try to think of it this way: Compared to your friends in the U.S., you're already a day ahead of schedule! Not all time zones are created equal Time zones are a long-standing tradition, but they're not a precise science. The People's Republic of China uses one standardized clock—it's the same time in Chengdu as it is in Beijing, according to native watches. But according to Western systems, the nation should cover five distinct zones. Some places—including Calcutta, Newfoundland and central Australia—use a half-hour time difference. Not all days are created equal, either If you live in Miami and visit Juneau, there's only a four-hour time difference. But if it's January, you're in for a shock: Miami enjoys 16 hours of sunlight in the wintertime, and Juneau sees only a few hours, and these are pretty dim (Alaska in winter looks like either perpetual night or a sleepy late-afternoon). The actual time difference can be deceiving, because the amount of sunlight varies in different parts of the world (during Iceland summers, the sun may still be shining at 2 a.m.). Alaskans, Icelanders and Norwegians are accustomed to the seasonal changes, but the solar patterns can be jarring to visitors and lead to extended periods of fatigue, depression or sleeplessness. Check out Al Pacino's character in the movie “Insomnia,” a Californian detective who stays awake for days because he's so overwhelmed by Alaska's 24-hour summer sunlight. This disorientation still is considered jet lag, even if it has nothing to do with actual time differences. Seasonal weather patterns also take their toll on travelers: New Zealand and Australia experience seasons opposite of the United States (in Sydney, Christmas falls in the dry heat of summer). Meanwhile, most of India has never seen snow, but the monsoons drench the Indian landscape for months at a time. Keep the weather in mind before you plan your trip to Queensland or the Taj Mahal—after all, high and low tourist seasons usually revolve around climate changes. Take a sick day In a way, jet lag is just like catching a cold: Inconvenient but harmless, it's nothing that won't go away in a day or two. Medicate your jet lag with deep breathing, a few aspirin, lots of water and plenty of rest. Like a minor fever, jet lag will break, and you'll soon feel better than ever, no matter what hour it is. http://tinyurl.com/3e2tz3

The biggest mistake that people make, when it comes to overcoming a change in time is to eat the food on the airplane (or the airport) without regards to time. The basic rule is that you eat when travelling eat, but your fast when travelling west. Your body's internal clock is controlled by your eating times in many ways, so you want to ensure that you eat your meals in a way that allows your body clock to adjust. A flight leaving North American in the evening will be after dinner (so don't eat a second dinner on the airplane), but eat breakfast on the airplane because it's being served near breakfast time in your new arrival time zone. Eat your meals at the approximate proper time for your destination. If you are flying from Europe to North America, your flight generally will leave around lunchtime, but also arrive around lunchtime. Eat only ONE lunch. Your internal clock will be off if you eat two lunches.