Controversies in Vitamin D: A Statement From the Third International Conference

Abstract

The Third International Conference on Controversies in Vitamin D was held in Gubbio, Italy, September 10–13, 2019. The conference was held as a follow‐up to previous meetings held in 2017 and 2018 to address topics of controversy in vitamin D research. The specific topics were selected by the steering committee of the conference and based upon areas that remain controversial from the preceding conferences. Other topics were selected anew that reflect specific topics that have surfaced since the last international conference. Consensus was achieved after formal presentations and open discussions among experts. As will be detailed in this article, consensus was achieved with regard to the following: the importance and prevalence of nutritional rickets, amounts of vitamin D that are typically generated by sun exposure, worldwide prevalence of vitamin D deficiency, the importance of circulating concentrations of 25OHD as the best index of vitamin D stores, definitions and thresholds of vitamin D deficiency, and efficacy of vitamin D analogues in the treatment of psoriasis. Areas of uncertainly and controversy include the following: daily doses of vitamin D needed to maintain a normal level of 25OHD in the general population, recommendations for supplementation in patients with metabolic bone diseases, cutaneous production of vitamin D by UVB exposure, hepatic regulation of 25OHD metabolites, definition of vitamin D excess, vitamin D deficiency in acute illness, vitamin D requirements during reproduction, potential for a broad spectrum of cellular and organ activities under the influence of the vitamin D receptor, and potential links between vitamin D and major human diseases. With specific regard to the latter area, the proceedings of the conference led to recommendations for areas in need of further investigation through appropriately designed intervention trials. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Hypovitaminosis D and the endocrine phenotype of COVID-19

“…Change to an indoor lifestyle and lack of food fortification with VD is likely the main reason accounting for the higher prevalence of low circulating VD levels in Italy and in other Mediterranean Countries vs many other central and North European Countries in which this is systemically the rule from several decades due to the low sun exposure leading to what is defined Scandinavian paradox [ 54 , 55 ]. In fact, a geographical overlap between high prevalence of hypovitaminosis D and elevated number and severity of COVID-19 cases has been observed [ 43 ].…”

“…A few other studies reported an association between COVID-19 prevalence and related mortality with latitude and consequent sunlight availability [ 56 ]. Importantly, home confinement is the most used measure in order to prevent the spreading of SARS-CoV-2 infection but the drawback of this extremization of the above mentioned progressive changes in lifestyle may be the worsening in the VD status in already at huge risk patients particularly in heavily VD-deficient countries [ 54 ].…”

Mechanisms of Bone Impairment in Sickle Bone Disease

“…Recently, vitamin D deficiency has emerged as a public health concern due to its skeletal and extra-skeletal effects [ 18 ]. Children with SCD show a high prevalence of this condition, ranging from 56% to 96% [ 19 ].…”

The Relationship Between Vitamin D Serum Levels and Rheumatoid Arthritis Activity in a Sample of Syrian Patients- a cross-sectional observational study

“…[4] Vitamin D levels were reported to be lower in patients with autoimmune diseases than in healthy controls. [5][6][7]. Several animal studies have shown the role of vitamin D supplementation in controlling many autoimmune diseases such as arthritis and autoimmune encephalomyelitis.…”