Comment by Aerroon

I guess northern Europe must be an unpopulated wasteland where everybody's health just instantly declines.

I find these explanations to these studies so bizarre. We know that there are large populations living significantly further north, who don't get sunlight in the morning in winter, no matter whether there's DST or not. We also know that they get almost perpetual light during summer. If these explanations were true then you would expect a country like Sweden to have an impact on life expectancy and illness from this. But it's not. It's about as rich as Canada and has about the same life expectancy.