Effect of Vitamin D Supplementation on Body Composition and Physical Fitness in Healthy Adults: A Double-Blind, Randomized Controlled Trial.

What Was Tested

This randomized controlled trial looks at Vitamin D, K2, Magnesium and Zinc.

This study aimed to clarify whether 1 year of vitamin D3 supplementation has a direct effect on body composition and physical fitness in healthy adults.

Who Took Part

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

How the Study Was Run

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

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

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

Lean body mass and percentage body fat were determined.

Physical fitness including hand grip strength, leg extension power and cardiorespiratory fitness (CRF) were assessed.

Serum 25-hydroxyvitamin D (25[OH]D) and 1,25-dihydroxyvitamin D (1,25[OH]2D) concentrations were assessed using ELISA kits.

What Was Measured

PubMed files the paper under topics including Body Composition, Dietary Supplements, Healthy Volunteers, Physical Fitness and Vitamin D.

Author keywords: 25-Hydroxyvitamin D, Body fat, Cardiorespiratory fitness, Hand grip strength and Lean body mass.

What This Means in Plain Language

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

Results are reported in around 4 sentences of the abstract; we leave them to the paper itself rather than summarise them.

The publication is from 2019 (Annals of nutrition & metabolism), a journal based in Switzerland.

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