A new study of serum levels of vitamin D shows that 4000 to 8000 IU per day are required to keep your serum level in a range that will reduce the incidence of disease. This includes cancer, type 1 diabetes, and multiple sclerosis. Dr. Cedric Garland says that the incidence of many diseases could be reduced by half.
Here is the news article in Business Week: “Higher Vitamin D Level Could Cut Cancer Risk”
As I have described in many post, the amount of vitamin D required is different for each individual. The only way to know that you are getting enough is to have your serum 25(OH)D level tested. Serum levels should be maintained above 40 ng/ml, and for best results the level should be maintained between 60 to 80 ng/ml year round. You should only supplement with Vitamin D3.
For a better understanding of the science, here is the journal article that was published in Anticancer Research, International Journal of Cancer Research and Treatment, made available in its entirety by Grass Roots Health.
CEDRIC F. GARLAND, CHRISTINE B. FRENCH, , LEO L. BAGGERLY, and ROBERT P. HEANEY (here is the url in case you cannot go there from the above link http://www.grassrootshealth.net/garland02-11)
“This paper provides a long awaited insight into a dose-response relationship between orally administered vitamin D3 and the resulting levels of serum 25(OH)D in over 3600 citizens. The results will allow new definition of high vitamin D dose safety and reduce concerns about toxicity. This is a landmark contribution in the vitamin D nutrition field!”
– Pandemic Survivor