Keeping up with D news

Two new studies brought to my attention by Gretchen of Denver:

The data were very clear, showing that individuals in the group with the lowest blood levels had the highest rates of breast cancer, and the breast cancer rates dropped as the blood levels of vitamin D increased. The serum level associated with a 50 percent reduction in risk could be maintained by taking 2,000 international units of vitamin D3 daily plus, when the weather permits, spending 10 to 15 minutes a day in the sun.
--Cedric Garland, Dr.P.H.

Through this meta-analysis we found that raising the serum level of 25-hydroxyvitamin D to 34 ng/ml would reduce the incidence rates of colorectal cancer by half. We project a two-thirds reduction in incidence with serum levels of 46ng/ml, which corresponds to a daily intake of 2,000 IU of vitamin D3. This would be best achieved with a combination of diet, supplements and 10 to 15 minutes per day in the sun.
--Edward D. Gorham, Ph.D.