I remember 10 years ago someone mentioned that Vitamin D was the most effective Vitamin...and that we do one thing that causes more cancer and disease than anything....
...Wearing sunscreen.
Sunscreen blocks the absorption of Vit D....Vit D has been so reduced in our bodies from using sunscreen (and also, skin cancer has grown exponentially, too)
We are finding more and more, Vitamin D is so important
Most people also work indoors which makes it harder to get Vitamin D from the sun.
I saw a 2 hour lecture about a week ago on Dish Network's Universityhouse channel done by a UCLA Phd on this very topic. Not trying to be a wise ass or anything, but what sunscreen does is block UVb penetration into your skin. UVb reacts with a layer in your skin which causes your body to produce Vitamin D. People with a lot of melanin in their skin, i.e., dark skinned people, have trouble with being vitamin D deficient, especially at higher latitudes, and especially in the winter. If you have a lot of melanin in your skin it acts as a natural filter to UVb. The professor who was doing the lecture said you only really get good D3 production between the hours of 11:00AM and about 2:00PM and you have to have 50% of your body uncovered and in direct sunlight for at least 20 minutes to reach the blood serum levels needed to fight off various diseases. This lecturer was talking citing six different studies which showed from 50%-75% reductions in several types of cancer, MS, influenza infection, and type 1 diabetes. I'll tell ya, after watching the case this lady made I went out and bought some D3 and started taking it daily.....