Vitamin D supplementation in the first 2 years and autism spectrum traits at 6-8 years - a randomized clinical trial.

What Was Tested

Researchers studied Vitamin D, K2, Magnesium and Zinc in this randomized controlled trial publication.

Who Took Part

The abstract describes 366 children taking part.

By PubMed's age tags, the people studied were infants, young children and children, both men and women.

Predictor variables were supplementation group, 25(OH)D concentrations measured during pregnancy and at ages 1 and 2 years, as well as 25(OH)D trajectories (high vs. low) derived from these time points.

How the Study Was Run

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

Neither the children nor the staff measuring them knew who was on Vitamin D, K2, Magnesium and Zinc, so expectations could not easily colour the readings.

ASD-related traits were assessed at mean age 7.2 years (SD 0.4) using the parent-reported Autism Spectrum Screening Questionnaire (ASSQ).

What Was Measured

PubMed files the paper under topics including Autism Spectrum Disorder, Vitamin D, Dietary Supplements, Finland, Cholecalciferol and Vitamins.

The authors tagged it with the keywords neurodevelopment and randomized clinical trial.

What This Means in Plain Language

The paper is a randomized and double-blind study of Vitamin D, K2, Magnesium and Zinc in 366 children.

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

Its findings take up roughly 4 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 (Journal of child psychology and psychiatry, and allied disciplines), a journal based in England.

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