The ratio of serum 24,25-dihydroxyvitamin D(3) to 25-hydroxyvitamin D(3) is predictive of 25-hydroxyvitamin D(3) response to vitamin D(3) supplementation.

What Was Tested

The paper reports a study of Vitamin D, K2, Magnesium and Zinc, published as a randomized controlled trial.

24,25-Dihydroxyvitamin D (24,25VD) is a major catabolite of 25-hydroxyvitamin D (25VD) metabolism, and may be physiologically active.

Their objectives were to: (1) characterize the response of serum 24,25VD(3) to vitamin D(3) (VD(3)) supplementation; (2) test the hypothesis that a higher 24,25VD(3) to 25VD(3) ratio (24,25:25VD(3)) predicts 25VD(3) response.

Who Took Part

The age groups tagged for this paper are young adults and adults, both men and women.

How the Study Was Run

The design is described as randomized, double-blind and placebo-controlled.

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

Neither the participants nor the staff measuring them knew who was on Vitamin D, K2, Magnesium and Zinc, so expectations could not easily colour the readings.

Some participants received a placebo instead of Vitamin D, K2, Magnesium and Zinc, giving a reference point.

What Was Measured

Their objectives were to: (1) characterize the response of serum 24,25VD(3) to vitamin D(3) (VD(3)) supplementation; (2) test the hypothesis that a higher 24,25VD(3) to 25VD(3) ratio (24,25:25VD(3)) predicts 25VD(3) response.

PubMed files the paper under topics including 24,25-Dihydroxyvitamin D 3, Cholecalciferol, Chromatography, Liquid, Dietary Supplements, Tandem Mass Spectrometry and Vitamin D.

What This Means in Plain Language

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

The publication is from 2011 (The Journal of steroid biochemistry and molecular biology), a journal based in England.

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