Significance of serum 24,25-dihydroxyvitamin D in the assessment of vitamin D status: a double-edged sword?

What Was Tested

Researchers studied Vitamin D, K2, Magnesium and Zinc in this randomized controlled trial publication.

24,25-Dihydroxyvitamin D [24,25(OH)2D] in serum may be both a nuisance and nutritionally valuable.

Who Took Part

By PubMed's age tags, the people studied were middle-aged adults, both men and women.

The researchers investigated the impact of 24,25(OH)2D3 on the performance of commercially available immunoassays for serum total 25-hydroxyvitamin D [25(OH)D] using (a) serum from a nationally representative sample of adults, (b) serum from a spiking experiment, and (c) data from the UK Vitamin D External Quality Assurance Scheme (DEQAS).

The researchers also investigated the utility of the serum ratio of 24,25(OH)2D3 to 25(OH)D as an index of inactivation and of response to vitamin D supplementation using randomized controlled trial (RCT) data.

How the Study Was Run

In design terms this was a randomized and double-blind study.

The participants were allocated by chance, so the Vitamin D, K2, Magnesium and Zinc group and the comparison group should start out alike.

As a double-blind Vitamin D, K2, Magnesium and Zinc study, the assignments were hidden from both participants and investigators until the end.

Measurement of 24,25(OH)2D in sera by a LC-MS/MS method allowed for an investigation of its impact on immunoassay-derived serum 25(OH)D values as well as its clinical utility.

The researchers report data from a nationally representative sample of adults, a recent vitamin D RCT in older adults, and DEQAS.

What Was Measured

The subject headings attached to it are 24,25-Dihydroxyvitamin D 3, Chromatography, Liquid, Cross Reactions, Dietary Supplements, Immunoenzyme Techniques, Linear Models and Tandem Mass Spectrometry.

What This Means in Plain Language

The paper is a randomized and double-blind study of Vitamin D, K2, Magnesium and Zinc.

Results are reported in around 5 sentences of the abstract; we leave them to the paper itself rather than summarise them.

The publication is from 2015 (Clinical chemistry), a journal based in England.

More context: the Vitamin D, K2, Magnesium and Zinc compound page, all human trials.