I'm more or less back at it today after a very addled few days. I was happy to see jetlag is making the news . It seems that shifts of 6 or more hours are especially tough because they can jar two parts of the superior chiasmatic nucleus "clocks" out of sync with each other. I have seen mention that you can reduce jetlag by changing the timing of your meals . I presume you wouldn't be allowed to have anything but beer and nuts, the Hitchhiker's Guide diet.
What is hardest for us is travelling with the kids, who seem to absolutely randomize their clocks (also relative to each other) for shifts of this size.
The best cure of all is taking lots of naps. You need a scientist to tell you that?