Evidence That Increasing Serum 25(OH)D Concentrations to 30 ng/mL in the Kingdom of Saudi Arabia and the United Arab Emirates Could Greatly Improve Health Outcomes.

Accumulating evidence supports the potential protective effects of vitamin D against chronic diseases such as Alzheimer's disease, autoimmune diseases, cancers, cardiovascular disease (ischaemic heart disease and stroke), type 2 diabetes, hypertension, chronic kidney disease, stroke, and infectious diseases such as acute respiratory tract diseases, COVID-19, influenza, and pneumonia, as well as adverse pregnancy outcomes. The respective evidence is based on ecological and observational studies, randomized controlled trials, mechanistic studies, and Mendelian randomization studies. However, randomized controlled trials on vitamin D supplementation have largely failed to show benefits, probably due to poor design and analysis.

A Narrative Review on the Potential Role of Vitamin D in the Prevention, Protection, and Disease Mitigation of Acute and Long COVID-19.

Purpose Of Review: The coronavirus disease 2019 (COVID-19) pandemic has challenged global health systems and economies from January 2020. COVID-19 caused by the infectious severe acute respiratory syndrome coronavirus (SARS-CoV-2) has acute respiratory and cardiometabolic symptoms that can be severe and lethal. Long-term physiological and psychological symptoms, known as long COVID-19, persist affecting multiple organ systems.

Targeted 25-hydroxyvitamin D concentration measurements and vitamin D supplementation can have important patient and public health benefits.

Over the past two decades, many studies reported the benefits of higher 25-hydroxyvitamin D [25(OH)D] concentrations for nonskeletal effects. Researchers found significant benefits in reducing risk of acute respiratory tract infections, many types of cancer, type 2 diabetes mellitus, premature death, and adverse pregnancy and birth outcomes. In addition, 25(OH)D concentrations are low for various reasons in several categories of people, including the obese, those with dark skin living at higher latitudes, the elderly, and those who do not eat much eggs, fish, meat, or vitamin D fortified milk.

Linking the metabolic syndrome and obesity with vitamin D status: risks and opportunities for improving cardiometabolic health and well-being.

The global death toll from noncommunicable diseases is exceptionally high, reported to cause 71% of global deaths worldwide. Metabolic syndrome risk factors, especially excessive adiposity and obesity, are at the heart of the problem resulting in increased co-morbidities such as cardiometabolic diseases and cancer, increased health costs, poorer quality of life, and shortened survival. Vitamin D can positively reverse many of these adverse effects and outcomes through blocking signaling mechanisms that predispose to cardiometabolic and metastatic disease.

Vitamin D from Ultraviolet-B Exposure or Oral Intake in Relation to Cancer Incidence and Mortality.

Purpose Of Review: This review summarizes the understanding of vitamin D's role in reducing risk of cancer incidence and mortality.

Recent Findings: Recent randomized clinical trials and observational studies of participants who took part in vitamin D supplementation studies provide increasing evidence that concentrations of serum 25-hydroxyvitamin D [25(OH)D] up to ~ 60 ng/ml are inversely correlated with all cancer and some specific cancers' incidence and death, with a stronger effect on survival and death than on incidence. Mechanisms linking vitamin D to effects on cellular proliferation, anti-angiogenesis, and anti-metastasis continue to be found.

The roles of UVB and vitamin D in reducing risk of cancer incidence and mortality: A review of the epidemiology, clinical trials, and mechanisms.

Global cancer incidence and mortality rates are high and increasing. Thus, it is imperative to find novel solutions to preventing cancer incidence and treating it at an affordable yet efficacious manner. The solar UVB-vitamin D-cancer hypothesis was first proposed in 1980 based on a geographical ecological study.

Molecular link between vitamin D and cancer prevention.

The metabolite of vitamin D, 1α,25-dihydroxyvitamin D₃ (also known as calcitriol), is a biologically active molecule required to maintain the physiological functions of several target tissues in the human body from conception to adulthood. Its molecular mode of action ranges from immediate nongenomic responses to longer term mechanisms that exert persistent genomic effects. The genomic mechanisms of vitamin D action rely on cross talk between 1α,25-dihydroxyvitamin D₃ signaling pathways and that of other growth factors or hormones that collectively regulate cell proliferation, differentiation and cell survival.

Transcriptional profiling of human cord blood CD133+ and cultured bone marrow mesenchymal stem cells in response to hypoxia.

Umbilical cord blood (UCB) and bone marrow (BM)-derived stem and progenitor cells possess two characteristics required for successful tissue regeneration: extensive proliferative capacity and the ability to differentiate into multiple cell lineages. Within the normal BM and in pathological conditions, areas of hypoxia may have a role in maintaining stem cell fate or determining the fine equilibrium between their proliferation and differentiation. In this study, the transcriptional profiles and proliferation and differentiation potential of UCB CD133(+) cells and BM mesenchymal cells (BMMC) exposed to normoxia and hypoxia were analyzed and compared.