Because of this, many North Americans choose to disbelieve it when doctors in the UK say that people living in the British Isles cannot get Vitamin D from the Sun over the winter until some time in March.
Having lives in Winnipeg and Seattle I'll say that darkness when I get to work and darkness when I leave work does not help things. Sure it's also cloudy during the day if I manage to go outside at all but it had to happen during typical work hours.