Role of Vitamin D Deficiency in Extraskeletal Complications: Predictor of Health Outcome or Marker of Health Status?
Abstract
The relationship of vitamin D with extraskeletal complications, such as cardiovascular disease, cancer, and autoimmune disease, is of major interest considering its roles in key biological processes and the worldwide high prevalence of vitamin D deficiency. However, the causal relationships between vitamin D and most extraskeletal complications are weak. Currently, a heated debate over vitamin D is being conducted according to two hypotheses. In this review, we first present the different arguments that suggest a major role of vitamin D in a very broad type of extraskeletal complications (hypothesis #1). We then present results from recent meta-analyses of randomized controlled trials indicating a lack of association of vitamin D with major extraskeletal complications (hypothesis #2). We discuss different issues (e.g., causality, confounding, reverse causation, misclassification, and Mendelian randomization) that contribute to the favoring of one hypothesis over the other. While ultimately only one hypothesis is correct, we anticipate that the results from the ongoing randomized controlled trials will be unlikely to reconcile the divided experts.
How strong is the evidence?
Evidence Hub reads this as a randomized trial. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design.
Read the paper
Related studies
- Effectiveness of Bisphosphonates and Denosumab on Risk of Vertebral Fractures in Prostate Cancer Patients Under Androgen Deprivation Therapies: A Real-World Prospective Study
- Osteoporosis-related fractures after spinal cord injury: a retrospective study from Brazil
- Serum 25-hydroxyvitamin D, parathyroid hormone, and mortality in older men
- Lack of Association between Vitamin D Insufficiency and Cardiovascular or Fracture Risk: A UK Biobank Study
- Muscle strength and body composition are clinical indicators of osteoporosis
- Incidence of bone protection and associated fragility injuries in patients with proximal femur fractures
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.