TweetThere is now wide scientific support1 for maintaining blood levels of vitamin D between 40 ng/ml – 80 ng/ml, with 60 ng/ml – 80 ng/ml now the gold standard range for cancer prevention. Surprisingly the researchers found that a supplemental dose of 9,600 IU of vitamin D per day enabled 97% of participants to reach 40 ng/ml – the bottom end of the protective range.
“We found that daily intakes of vitamin D by adults in the range of 4000-8000 IU are needed to maintain blood levels of vitamin D metabolites in the range needed to reduce by about half the risk of several diseases—breast cancer, colon cancer, multiple sclerosis, and type 1 diabetes,” said Cedric Garland, DrPH, professor of family and preventive medicine at UC San Diego Moores Cancer Center. “I was surprised to find that the intakes required to maintain vitamin D status for disease prevention were so high—much higher than the minimal intake of vitamin D of 400 IU/day that was needed to defeat rickets in the 20th century.”
Interest in larger doses was spurred in December of last year, when a National Academy of Sciences Institute of Medicine committee identified 4000 IU/day of vitamin D as safe for every day use by adults and children nine years and older, with intakes in the range of 1000-3000 IU/day for infants and children through age eight years old.
20-30 minutes of sun exposure produces 10,000 IU of vitamin D. In the current study no patient talking 10,000 IU of vitamin D daily came close to the vitamin D toxicity level of 200 ng/ml.
It is quite clear that when vitamin D levels are not maintained in a more optimal range than existing health problems can worsen. It is also now clear that significantly higher vitamin D intake may be required to keep vitamin D in a health-protective range.
Referenced Studies:

1. ^Higher Vitamin D Intake Recommended Anticancer Research 1.Cedric F. Garland, Christine B. French, Leo L. Baggerly, Robert P. Heaney.

TweetVitamin D is involved in the regulation of over 200 genes responsible for cellular growth, differentiation, cell death and blood vessel generation. The cell death (apoptosis) genes are especially important when it comes to considering the anti-cancer effects of Vitamin D