I moved to Canada 6 months ago and as soon as I got here I noticed that my sleeping habits had changed dramatically. Indeed, I sleep much more than I used to. I've always been insomniac and so I used to get around 6 to 7 hours of sleep per night, but now I get at least 8 to 9 hours. However, I always feel tired whereas I used to not feel tired at all on a 6-hour sleep. I thought it may not have any connection with me moving abroad but at least 5 friends of mine who also recently moved from France to Canada told me they experience the exact same thing. They all reported sleeping at least 1 to 2 hours more per night since they got here.
So I was wondering, why is it that we sleep more in certain countries than in others? I don't believe it has anything to do with language since we all have been attending international schools where we would hear and speak more than just 2 languages daily. Any other plausible explanation ?