Research published in the Journal Anticancer Research on February 21 concluded that markedly increasing the intake of vitamin D is necessary to reach blood levels that will prevent or cut the incidence of breast cancer and other major diseases. Although the levels identified from the research (4,000-8,000 IU daily) is considerably higher than those traditionally recommended by physicians they are within a range considered safe for daily use by the National Academy of Science Institute of Medicine in a December, 2010 report.
This research was based upon a survey of several thousand volunteers who were taking between 1000 and 10,000 IU of vitamin D daily. Blood samples were studied to determine the circulating level of 25-vitamin D that is the form in which most vitamin D circulates in the blood.
The researchers found that ” the daily intake of vitamin D by adults in the range of 4,000-8,000 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.” However, according to a recent National Health and Nutrition Examination Survey only about 10% of the United States population have levels in this range and those are mostly people who work outside.
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