Bioavailability of calcium supplements and the effect of Vitamin D: comparisons between milk, calcium carbonate, and calcium carbonate plus vitamin D.

What Was Tested

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

Their aim was to examine a regimen for calcium supplementation because various factors seem to be important for its bioavailability, and to examine the effect of adding vitamin D to the supplement.

Why It Was Studied

The participants were 20 healthy women aged 28-59 y (chi: 38 y).

Who Took Part

The abstract describes 20 women taking part.

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

How the Study Was Run

The researchers set it up as a randomized, placebo-controlled and crossover study.

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

A placebo (an inactive look-alike) gave the Vitamin D, K2, Magnesium and Zinc group a baseline to be compared against.

Each person switched between Vitamin D, K2, Magnesium and Zinc and the comparison at some point, usually with a gap in between.

What Was Measured

Topics PubMed links to this paper include Biological Availability, Calcium, Calcium Carbonate, Magnesium, Milk, Phosphates and Vitamin D.

What This Means in Plain Language

The paper is a randomized, placebo-controlled and crossover study of Vitamin D, K2, Magnesium and Zinc in 20 women.

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 publication is from 1996 (The American journal of clinical nutrition), a journal based in United States.

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