>>>You need at least 5000 international units per day or more.<<<
Geesh, I thought I had that covered with a half million units. But at 5,000 daily X3 people only equals a months coverage. Maybe I will just have to put on shorts and spend some time in the sun in January... Brrr.
At your latitude you could be outside all day in January and never get enough sunshine. You have to take vitamin d supplements to get enough.