Vitamin D supplementation and central adiposity in male shift workers: a randomized clinical trial on metabolic health.

What Was Tested

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

This study aimed to evaluate the effect of cholecalciferol supplementation on central adiposity, assessed by waist circumference (WC) and waist-to-height ratio (WHtR), among male shift workers.

Why It Was Studied

Vitamin D deficiency is common among individuals with obesity; however, the association between low 25-hydroxyvitamin D [25(OH)D] concentrations and adiposity remains unclear.

This study was registered in the Brazilian Registry of Clinical Trials (ReBEC) under identifier RBR-6CS352 on October 25, 2017.

Who Took Part

PubMed indexes the participants as adults and middle-aged adults, men only.

How the Study Was Run

In design terms this was a randomized, double-blind and placebo-controlled study.

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

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

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

Randomized, double-blind, placebo-controlled clinical trial involving 198 male shift workers employed by an iron ore extraction company in Minas Gerais, Brazil.

Plasma 25(OH)D concentrations, WC, and WHtR were evaluated at baseline and post-intervention.

What Was Measured

PubMed files the paper under topics including Dietary Supplements, Vitamin D, Cholecalciferol, Waist Circumference, Vitamin D Deficiency, Adiposity and Obesity, Abdominal.

What This Means in Plain Language

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

Its findings take up roughly 6 sentences of the abstract and are left out here on purpose; the source paper is the place to read them.

The publication is from 2026 (Sao Paulo medical journal = Revista paulista de medicina), a journal based in Brazil.

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