My doctor's advice: 15-30 minutes of sun per day, with more than just your face exposed. So yes, an hour a day might be sufficient. You don't need to sunbathe,

My doctor's advice: 15-30 minutes of sun per day, with more than just your face exposed. So yes, an hour a day might be sufficient. You don't need to sunbathe, luckily, and cloudy days count too. For me, this only counts from May to August: I'm pretty far north, and there isn't proper sun strength much of the year.