Jetlag when flying is a phenomenon where one feels tired, fuzzy, and generally fatigued, sometimes accompanied by dull headaches, due to a time zone change.

To reset your clock, there are several things you can do: o Stay up 24+ hours and go to sleep at the normal time for your destination. o Do not take a nap at your destination until it is the normal time to go to sleep. o When you wake up in the morning at your destination, go for a half hour walk in the bright morning sunlight. (If there is no sunlight, a bright light can substitute.) o Do not eat right before you go to sleep. Eat a light dinner. o Eat your meals according to the destination time zone. o Do not drink any alcoholic or caffeine-based beverages during your flight. Drinking other liquids is OK -- some people recommend drinking a lot of water. o Don't forget to adjust your watch.

Things that affect the sleep-wake cycle: o Sunlight. Properly timed bright light is very helpful. Turn off the lights in your bedroom at bedtime in your destination time zone, and leave the windowshades down in the morning. o Time of Meals o Amount of Sleep o It is easier to shift forward (e.g., waking up at noon home time instead of 7am) than it is to shift backward (e.g., waking up at to sleep at 2am). o Carbohydrates make you sleepy. Protein will keep you awake. Eat heavy carbohydrate meals for two days prior to the trip and a heavy protein one on the day of departure.

Some people recommend taking melatonin at dusk or bedtime (for your destination) a day or two before departure, and continue for a day or two after you arrive. Melatonin is produced by the pineal gland at the base of the brain during the night, and can be used to shift the circadian rhythm ("body clock"). Melatonin production is highest in the dark and is suppressed by exposure to sunlight. Melatonin is available from many health food stores (as a "food supplement"), but this may be changing due to action by the FDA. Melatonin is not a tested, FDA-approved drug. It is known to have side effects after extended usage. The drug is still available in Europe and Canada. BE SURE TO CONSULT YOUR PHYSICIAN BEFORE TAKING MELATONIN OR ANY OTHER DRUG.

Most flights are run according to the time of the departure point, not the destination. If you need to sleep according to the light/dark cycle of your destination, bring along eye shades and ear plugs.

Note that you can regulate your body's production of melatonin using light, achieving much the same effect as taking the drug.

Or you could give in, and just not plan to do anything really important during your first day in the new time schedule. If you can arrange it, just don't switch over to the new time zone, if you're only going to be there for a few days.

The Argonee National Laboratory anit-jet-lag diet is available as the file ftp://ftp.cs.cmu.edu/user/mkant/Travel/