The following is a summary of “Vitamin D: 100 years of discoveries, yet controversy continues,” published in the April 2023 issue of Diabetes and Endocrinology by Gallagher et al.
Significant advancements and findings have transpired in vitamin D research over the last century. Notable milestones in vitamin D research include the successful treatment of rickets in 1919, identifying vitamin D compounds, progress in vitamin D molecular biology, and enhanced comprehension of the endocrine regulation of vitamin D metabolism. In addition, established daily recommended intakes for vitamin D exist, and extensive clinical trials investigating the impact of vitamin D on the prevention of various illnesses have been conducted. Regrettably, these clinical trials have not met the anticipated outcomes envisioned a decade ago. In most clinical trials, diverse dosages and delivery modes failed to demonstrate vitamin D’s effectiveness in preventing fractures, falls, cancer, cardiovascular ailments, type 2 diabetes, asthma, and respiratory infections. While apprehensions regarding the adverse effects of prolonged administration of high doses, such as hypercalcemia and nephrocalcinosis, have persisted for forty years, certain clinical studies conducted in the last five years have revealed novel and unforeseen unfavorable outcomes.
The elderly population (65 years and above) may experience unfavorable outcomes such as heightened incidence of fractures, falls, and hospitalizations. Several of these clinical trials were adequately powered for a primary outcome; however, they needed dose-response studies and were insufficiently powered for secondary analyses. Additionally, it is imperative to prioritize the safety considerations of administering high dosages of vitamin D supplements, especially among the elderly population. Furthermore, notwithstanding the widespread recommendations by osteoporosis societies regarding the amalgamation of calcium supplements with vitamin D, there still needs to be more information regarding their effectiveness and impact on fracture risk in the most susceptible populations. Further clinical studies are required for individuals with severe vitamin D insufficiency, characterized by serum 25-hydroxyvitamin D levels below 25nmol/L [10ng/mL]. In this Personal View, we provide a concise overview and analysis of significant findings and debates about the domain of vitamin D.
Source: sciencedirect.com/science/article/abs/pii/S2213858723000608