Vitamin D(3) is more potent than vitamin D(2) in humans.

What Was Tested

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

The aim of the study was to compare the potencies of D2 and D3.

Why It Was Studied

Published studies yield mixed results.

Who Took Part

The abstract describes 33 adults taking part.

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

The trial used a single-blind, randomized design in 33 healthy adults.

Principal outcome variables were area under the curve for incremental total 25-hydroxyvitamin D [25(OH)D] and change in calciferol content of sc fat.

How the Study Was Run

The design is described as randomized and single-blind.

Random assignment meant chance, not the researchers, decided who got Vitamin D, K2, Magnesium and Zinc and who got the comparison, which limits bias.

In this single-blind Vitamin D, K2, Magnesium and Zinc study one party knew the assignments and the other did not.

What Was Measured

The subject headings attached to it are Area Under Curve, Body Composition, Body Mass Index, Cholecalciferol, Dietary Supplements, Ergocalciferols and Hydroxycholecalciferols.

What This Means in Plain Language

The paper is a randomized and single-blind study of Vitamin D, K2, Magnesium and Zinc in 33 adults.

With fewer than 40 people, it is a small study, so it is better read as an early signal for further research than as a settled answer.

The abstract goes on to report its results in about 8 sentences; this page does not restate them, so read the paper for the findings and their limits.

The publication is from 2011 (The Journal of clinical endocrinology and metabolism), a journal based in United States.

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