The Role of Vitamin D in Inflammatory Bowel Diseases: From Deficiency to Targeted Therapeutics and Precise Nutrition Strategies

Background: Vitamin D plays a crucial role in immune modulation, gut barrier integrity, and inflammation regulation, making it highly relevant in inflammatory bowel disease (IBD). IBD patients often exhibit vitamin D deficiency, which has been linked to increased disease activity, impaired mucosal healing, and a higher risk of complications, including infections and osteoporosis. Methods: This review examines the biological functions of vitamin D in maintaining intestinal homeostasis, particularly in the context of IBD. It discusses the prevalence and consequences of vitamin D deficiency in IBD, including its potential to exacerbate disease progression, impair treatment efficacy, and negatively impact long-term health outcomes. Furthermore, therapeutic strategies to address vitamin D deficiency are explored, including supplementation approaches, dosing strategies, and precision nutrition interventions that aim to personalize vitamin D management based on individual patient needs and disease characteristics. Results: By synthesizing the latest evidence, this review highlights the critical role of vitamin D in IBD management, underlining how optimal vitamin D levels may not only improve disease control but also enhance patient quality of life and reduce the risk of long-term complications associated with the disease. Conclusions: Understanding the importance of vitamin D in IBD could help refine treatment strategies and promote better health outcomes for affected individuals.