gut microbiome

probiotics + vitamin d

Vitamin D and probiotics act on overlapping pathways in the gut. Vitamin D supports vitamin D receptor (VDR) activity in the intestinal lining, which probiotics rely on for their anti-inflammatory and barrier-strengthening effects, while some probiotic strains appear to modestly raise circulating vitamin D. Randomized trials suggest combined supplementation can outperform either alone for some inflammatory and gut-barrier endpoints, though the evidence base is still limited.