Average blood levels of vitamin D appear to have decreased in the United States between 1994 and 2004, according to a report in the March 23 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Clinicians previously believed the major health problems associated with vitamin D deficiency were rickets in children and reduced bone mineral content in adults, conditions reduced by fortifying foods with vitamin D, according to background information in the article. More recently, insufficient vitamin D levels have been associated with cancer, heart disease, infection and suboptimal health overall. Evidence suggests that levels of 30 nanograms per milliliter to 40 nanograms per milliliter may be needed for optimum health.
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