New test detects vitamin D more accurately

Jan. 27, 2012 at 9:04 PM

GAITHERSBURG, Md., Jan. 27 (UPI) -- It's estimated most U.S. adults may be deficient in vitamin D but blood sample testing may yield inaccurate measurements of vitamin D levels, researchers say.

Karen Phinney of the National Institute of Standards and Technology, an agency of the U.S. Department of Commerce, and colleagues said medical research suggests vitamin D deficiency or insufficiency may be more common than previously thought.

Measuring vitamin D itself doesn't work because it is rapidly changed into another form in the liver, Phinney said.

"That's why current methods detect levels of a vitamin D metabolite, or 25(OH)D. However, the test methods don't always agree and produce different results," Phinney said in a statement.

To help laboratories detect consistent and accurate methods, the researchers developed a Standard Reference Material, or SRM 972, the first certified reference material for the determination of the metabolite in human serum -- a component of blood.

The researchers developed four versions of the standard, with different levels of the vitamin D metabolites 25(OH)D2 and 25(OH)D3 in human serum.

In addition, the researchers found the metabolite 3-epi-25(OH)D in the adult human serum samples, which was previously thought to only exist in the blood of infants.

"This reference material provides a mechanism to ensure measurement accuracy and comparability and represents a first step toward standardization of 25(OH)D measurements," the researchers said.

The findings were published in the journal Analytical Chemistry.

Related UPI Stories
Latest Headlines
Trending Stories
Multiple attacks escalate Jerusalem violence; gun restrictions could ease"
Genetic changes could make pig organs usable for human transplant
Five Democratic presidential candidates meet in Las Vegas for first debate
Confederate flag group charged with terrorist threats
Report: MH17 downed by Russian-made missile