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Vitamin D Deficiency is Associated with Increased Disease Activity in Patients with Inflammatory Bowel Disease.

Another study confirming what many here already know, the link between crohn's disease activity and vitamin D status.

open access https://www.mdpi.com/2077-0383/8/9/1319

Vitamin D Deficiency is Associated with Increased Disease Activity in Patients with Inflammatory Bowel Disease.

Hausmann, Kubesch, Amiri , Filmann, Blumenstein

Department of Internal Medicine, Goethe-University

Frankfurt, Germany

2019 Aug

Vitamin D has an inhibitory role in the inflammatory signaling pathways and supports the integrity of the intestinal barrier. Due to its immunomodulatory effect, vitamin D plays a role in chronic inflammatory bowel disease (IBD) and a deficiency is associated with an increased risk for a flare. We aimed to investigate to what extent the 25-hydroxyvitamin D (25(OH)D3) level correlates with disease activity and whether a cut-off value can be defined that discriminates between active disease and remission.

Patients with IBD, treated at the University Hospital Frankfurt were analyzed retrospectively. The 25(OH)D3 levels were correlated with clinical activity indices and laboratory chemical activity parameters. A deficiency was defined as 25(OH)D3 levels <30 ng/mL.

A total of 470 (257 female) patients with IBD were included, 272 (57.9%) with Crohn's disease (CD), 198 (42.1%) with ulcerative colitis (UC). The median age of the patients was 41 (18-84). In 283 patients (60.2%), a vitamin D deficiency was detected. 245 (53.6%) patients received oral vitamin D supplementation, and supplemented patients had significantly higher vitamin D levels (p < 0.0001). Remission, vitamin D substitution, and male gender were independently associated with the 25(OH)D3 serum concentration in our cohort in regression analysis. A 25(OH)D3 serum concentration of 27.5 ng/mL was the optimal cut-off value.

Vitamin D deficiency is common in IBD patients and appears to be associated with increased disease activity. In our study, vitamin D levels were inversely associated with disease activity. Thus, close monitoring should be established, and optimized supplementation should take place.
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The how and the why is explained is several studies. This is one of the more readable ones.

Vitamin D modulates innate immunity by enhancing autophagy, increasing clearance of macrophage penetrating bacteria like Crohn's disease associated E Coli.

Seems to have an effect on a special type of treg cells too.

I used vitamin d supplements during the entire duration of my condition so for about 10 years now. I find really high doses are not better. 1000-2000iu during the summer are fine, while 3000-4000iu in the winter are fine, any higher and ,even though you'll feel better in some ways, you also start to get side effects along with the benefits.

Therapeutic effect of vitamin d supplementation in a pilot study of Crohn's patients.