I suffered terribly from jet lag when I was younger. Some trips were almost completely eaten by it.
Strangely, with age I stopped getting jet-lagged. Even though I’m physiologically incapable of sleeping on airplanes, I switch over to local time with great ease both going there and returning.
Clarissa's Blog 
“with age I stopped getting jet-lagged”
The first time or two I went to Europe I wasn’t jet-lagged in either direction.
The last few times I wasn’t jet-lagged going to Europe but going to the US I’d absolutely conk out soon after arriving from the airport… as in more or less alert one minute sitting on a couch and then sprawled out deep asleep the next and all but impossible to wake up for 14-15 hours. Then the next morning I’d be fine.
No idea why…..
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