Research

Hormonal

Vitamin D signaling in innate immune cells (macrophages/dendritic cells) stimulates the intracrine synthesis of 1,25-dihydroxyvitamin D, which directly induces the expression of antimicrobial proteins (cathelicidin, beta-defensin 2) and enhances autophagy to combat intracellular pathogens like Mycobacterium tuberculosis.

Ensure your Vitamin D levels are sufficient, as the immune system needs this nutrient to produce antimicrobial proteins that fight bacteria and viruses. This is not just about bone health; your immune cells actively use Vitamin D to fight infections. If you are deficient, your immune cells cannot effectively produce these protective proteins, regardless of how much you take.

GoodSupportsHIGH confidence
At an innate level, intracrine synthesis of 1,25D by macrophages and dendritic cells stimulates expression of anti-microbial proteins such as cathelicidin, as well as lowering intracellular iron concentrations via suppression of hepcidin. By potently enhancing autophagy, 1,25D may also play an important role in combatting intracellular pathogens such as M. tuberculosis and viral infections.
Emma L. Bishop et al. · JBMR Plus · 2020

Why this rating

The paper is a comprehensive review citing numerous in vitro, in vivo, and clinical studies, though it notes species-specific differences (primates vs rodents).

Source

Vitamin D and Immune Regulation: Antibacterial, Antiviral, Anti‐Inflammatory

Emma L. Bishop et al. · JBMR Plus · 2020

DOI 10.1002/jbm4.10405

narrative_reviewCited 376×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →