Calcium plus vitamin D supplementation and the risk of fractures.

What Was Tested

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

Who Took Part

According to the abstract, 36,282 women were involved.

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

The researchers recruited 36,282 postmenopausal women, 50 to 79 years of age, who were already enrolled in a Women's Health Initiative (WHI) clinical trial.

How the Study Was Run

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

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

Blinding on both sides kept the women and researchers unaware of who received Vitamin D, K2, Magnesium and Zinc.

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

Bone density was measured at three WHI centers.

What Was Measured

The subject headings attached to it are Bone Density, Calcium, Calcium Carbonate, Drug Combinations, Drug Interactions, Estrogen Replacement Therapy and Fractures, Bone.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of Vitamin D, K2, Magnesium and Zinc in 36,282 women.

With several hundred people or more, it is a fairly large study for this kind of research.

Results are reported in around 6 sentences of the abstract; we leave them to the paper itself rather than summarise them.

The publication is from 2006 (The New England journal of medicine), a journal based in United States.

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