What affordable remedy will help with jet lag?

* A friend swears by melatonin tablets to help with jet lag when travelling on long haul flights.

She purchases them online at great expense, but is convinced that they are worth the trouble. Is there an affordable remedy that will have a similar effect, and is preferably available locally?

>> Melatonin is a hormone which determines the pattern of sleeping and waking in the body. Levels of this hormone decrease with age, with the body producing only half the amount at the age of 60 than it did at the age of 20.