Vitamin D and schizophrenia: 20 years on.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of primarily observational studies, combined with narrative synthesis of animal and intervention data
PubMed 33500553 · doi:10.1038/s41380-021-01025-0
What was done
The authors conducted a systematic review and meta-analysis to evaluate the association between vitamin D deficiency and schizophrenia or first-episode psychosis, alongside a narrative review of rodent developmental deficiency models and clinical supplementation trials.
What was found
The abstract provides no specific numerical values, odds ratios, or effect sizes. It reports that the meta-analysis confirms an increased risk of vitamin D deficiency in patients with schizophrenia compared to controls, extending this finding to first-episode psychosis. In animal models, developmental vitamin D deficiency alters brain development and dopamine pathways, whereas adult deficiency produces only subtle changes not specific to schizophrenia phenotypes. Clinical trials of vitamin D supplementation in schizophrenia yielded inconsistent results.
Why it matters
This review synthesizes two decades of epidemiological and preclinical data, confirming the statistical association between vitamin D deficiency and psychosis while urging caution regarding causality due to lifestyle and health confounders.
Limits
The abstract reports no numerical statistics, sample sizes, or study counts. The observed associations are heavily subject to reverse causation and residual confounding from diet, physical activity, and physical comorbidities in psychiatric populations.
Cited by
- supports There is a scientific hypothesis proposing that individuals with ancestry from equatorial climates are more susceptible to schizophrenia when living in colder climates due to the activation of genetic risk factors.