Vitamin D supplementation during Antarctic winter.

What Was Tested

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

Persons with limited exposure to ultraviolet B light, including space travelers, may not receive enough vitamin D.

Who Took Part

According to the abstract, 55 subjects were involved.

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

This was a 5-mo, prospective, randomized, double-blind study of vitamin D supplementation.

An additional 7 subjects did not take supplements or took supplements of their own choosing.

How the Study Was Run

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

Because people in this Vitamin D, K2, Magnesium and Zinc study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

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

It was conducted during winter in Antarctica at the McMurdo Station, when ultraviolet B radiation levels are essentially zero.

Blood samples were collected about every 2 mo during the winter.

What Was Measured

PubMed files the paper under topics including Antarctic Regions, Bone Density Conservation Agents, Diet, Dietary Supplements, Seasons, Sunlight and Vitamin D.

What This Means in Plain Language

The paper is a randomized and double-blind study of Vitamin D, K2, Magnesium and Zinc in 55 subjects.

Results are reported in around 3 sentences of the abstract; we leave them to the paper itself rather than summarise them.

The publication is from 2009 (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.