I’m Swiss, but I was born and raised in the Gulf states. When I visit Switzerland during the cold season, I immediately become depressed, irritable, and in a bad mood. I prefer the heat 100%. I don’t think I could live in a place with a cold climate and be happy.
That was my first thought too. My understanding is that Nordic countries do think about vitamin D deficiency (especially this time of year) so it’s common to see stuff like cod liver oil and other ways to supplement vitamin D, besides just eating fish. Figured Switzerland would be similar.