Table 1.

Potential beneficial effects of vitamin D in asthma.

Vitamin D effects on the Innate Immune System:

- Enhances epithelial barrier function and chemokine secretion.

- Increases production of antimicrobial peptides in macrophages and monocytes.

- Enhances generation of reactive oxygen and nitrogen species in leukocytes.

Vitamin D effects on the Adaptive Immune System:

- Promotes tolerogenic T regulatory cells (Tregs).

- Inhibits development of pathogenic effector Th1 and Th17 cells.

- Inhibits B cells, plasma cell differentiation, and Ig production.

Unproven potential clinical benefits:

- Protection against asthma development in early life.

- Protection against respiratory infections, a risk factor for asthma onset and exacerbations.

- Enhances anti-inflammatory response to corticosteroids.