"Vitamin D metabolites increase communication between cells by switching on a protein that blocks aggressive cell division," said Garland. "As long as vitamin D receptors are present tumor growth is prevented and kept from expanding its blood supply. Vitamin D receptors are not lost until a tumor is very advanced. This is the reason for better survival in patients whose vitamin D blood levels are high."
"Women in the high serum group had an average level of 30 nanograms per milliliter (ng/ml) of 25-hydroxyvitamin D in their blood. The low group averaged 17 ng/ml. The average level in patients with breast cancer in the United States is 17 ng/ml."
"The study has implications for including vitamin D as an adjuvant to conventional breast cancer therapy," said co-author Heather Hofflich, DO, UC San Diego associate professor in the Department of Medicine."
"A 2011 meta-analysis by Garland and colleagues estimated that a serum level of 50 ng/ml is associated with 50 percent lower risk of breast cancer. While there are some variations in absorption, those who consume 4,000 International Units (IU) per day of vitamin D from food or a supplement normally would reach a serum level of 50 ng/ml. Garland urged patients to ask their health care provider to measure their levels before substantially increasing vitamin D intake."
Experts in the field of Vitamin D research recommend 40-70 ng/ml. See chart at http://www.grassrootshealth.net.
Make sure that your multiple vitamin includes adequate levels of Vitamin D3. I recommend Shaklee Vita-Lea, Vita-Lea Gold and Vitalizer for a basic foundation plus supplemental Vita-D3 to get your blood levels into optimum range. For children, I recommend Shaklee's chewable multiple vitamin, Incredivites, which contains 600 IU per two tablet serving.
Of the 300 plus men and women -- average age 65 -- who had been taking Shaklee nutritional supplements for 20 years or more and participated in Shaklee's Landmark Study, not one had sub-optimal levels of Vitamin D. Since Vitamin D deficiency is so common, that is an impressive finding!