Scientists have long known that vitamin D helps people with inflammatory bowel disease (IBD), and now they finally know why. A new Mayo Clinic-led study shows how vitamin D essentially reprograms the immune system to stop attacking the beneficial bacteria living in the gut.
The findings, published in Cell Reports Medicine, build on years of clinical observation linking vitamin D deficiency to worse IBD outcomes. However, unlike previous research, the new study maps the precise immune mechanism at work—a detail that could reshape how doctors approach treatment.
