About 7% of people have rare diseases, Vitamin D rarely studied for rare diseases

The Role of Vitamin D in Rare Diseases—A Clinical Review

Biomedicines 2025, 13(3), 558; https://doi.org/10.3390/biomedicines13030558

by Czesław Ducki 1,2,Marta Wojtkiewicz 2,3ORCID,Marcin Bartoszewicz 2ORCID andPiotr Fiedor 2,*

1 Mazovian Specialized Health Center in Pruszków, Partyzantów 2/4, 05-802 Pruszków, Poland

2 University of Economics and Human Sciences in Warsaw, Okopowa 59, 01-043 Warsaw, Poland

3 Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland

Background/Objectives: Patients suffering from rare diseases are particularly vulnerable to vitamin D deficiency. The role of vitamin D status in rare disease management remains insufficiently investigated and employed in routine clinical practice.

Methods: This review analyses current data on vitamin D status in selected rare diseases of organs involved in vitamin D metabolism: skin (epidermolysis bullosa, morphea), liver (autoimmune hepatitis, primary biliary cholangitis, primary sclerosing cholangitis), kidney (Alport syndrome, Fabry disease), and cystic fibrosis as a model of a systemic rare disease. Additionally, this review critically examines potential drug–vitamin D interactions in the context of rare disease patient polypharmacy.

Results: Evidence suggests that vitamin D deficiency is prevalent in rare disease patient populations, often at once exacerbating and being simultaneously exacerbated by the underlying condition. Vitamin D deficiency correlates with worse clinical outcomes and lower quality of life across the examined diseases. Immunoregulatory properties of vitamin D appear relevant for rare diseases with autoimmune components.

Conclusions: An urgent need for developing disease-specific clinical practice guidelines, implementing routine vitamin D monitoring in rare disease patient care, and introducing tailored supplementation under the principles of precision medicine is emphasized.

📄 Download the PDF from VitaminDWiki

Rare Disease studies in VitaminDWiki

• Rare diseases: 1 in 10 Americans (some are helped by Vitamin D) - 2023

• Rare diseases hit fewer than 1 in 1500 people, but 1 in 12 people have a rare disease (vitamin might D help)

Note: VitaminDWiki rarely reports on rare diseases. Not enough visitors would be interested in treated any specific disease