Influence of Vitamin D Supplementation by Simulated Sunlight or Oral D3 on Respiratory Infection during Military Training.

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, 250 men were involved.

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

In study 1, 1644 military recruits were observed across basic military training.

How the Study Was Run

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

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

As a double-blind Vitamin D, K2, Magnesium and Zinc study, the assignments were hidden from both participants and investigators until the end.

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

URTI was diagnosed by a physician (study 1) and by using the Jackson common cold questionnaire (study 2).

Serum 25(OH)D, salivary secretory immunoglobulin A (SIgA), and cathelicidin were assessed by liquid chromatography-mass spectrometry LC-MS/MS and enzyme-linked immunosorbent assay.

What Was Measured

The subject headings attached to it are Cholecalciferol, Immunity, Mucosal, Military Personnel, Respiratory Tract Infections, Sunlight and Surveys and Questionnaires.

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 250 men.

Its findings take up roughly 8 sentences of the abstract and are left out here on purpose; the source paper is the place to read them.

The publication is from 2021 (Medicine and science in sports and exercise), a journal based in United States.

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