vitamin d is important for the development, growth, and mineralization of the skeletal in neonates and children. vitamin d is essential for intestinal absorption of calcium. vitamin d is metabolized to 25-hydroxyvitamin d and then to 1,25-dihydroxyvitamin d. pregnant women in developed countries often have insufficient serum concentrations of 25-hydroxyvitamin d and a supplementation of vitamin...

A mathematical model is described for estimating changes in plasma 25-hydroxyvitamin D (25(OH)D) levels throughout the year as a consequence of varying the oral intake of vitamin D and the behaviour outdoors of white British adults resident in different regions of the UK. The model yields seasonal and geographical patterns of 25(OH)D concentrations that agree closely with observational studies....

OBJECTIVE To assess the relationship between low maternal serum 25-hydroxyvitamin D levels and gestational diabetes mellitus in Turkish pregnant women according to the severity of 25-hydroxyvitamin D deficiency and assess intact parathyroid hormone levels in women with gestational diabetes mellitus and controls with low and sufficient 25-hydroxyvitamin D levels. METHODS We analyzed serum 25-h...

OBJECTIVE Considering that epidemiological studies show that suicide rates in many countries are highest in the spring when vitamin D status is lowest, and that low vitamin D status can affect brain function, we sought to evaluate if a low level of 25-hydroxyvitamin D [25(OH)D] could be a predisposing factor for suicide. METHOD We conducted a prospective, nested, case-control study using seru...

The most widely used indicator of vitamin D status is the measurement of 25-hydroxyvitamin D [25(OH)D] in either serum or plasma. Several studies have reported discrepancies between the results of assays used to measure 25(OH)D, however, which calls into question the ability of 25(OH)D assays to reflect accurately the vitamin D status of individuals. The National Institute of Standards and Tech...

OBJECTIVE The aim of this study was to analyze the correlation of serum 25-hydroxyvitamin D level with vascular calcification in patients treated with hemodialysis. METHODS As a cross-sectional study, 126 patients receiving maintenance hemodialysis (MHD) in our hospital were enrolled in this study. According to the serum 25-hydroxyvitamin D level, the patients were divided into 25-hydroxyvita...

Lower serum level of 25-hydroxyvitamin D is associated with several negative outcomes. However, previous studies have indicated that 25-hydroxyvitamin D is associated with lung cancer risk and survival, but presented controversial results.PubMed and Embase databases were searched update to August 2017 to identify and quantify the potential association between 25-hydroxyvitamin D and lung cancer...

Background & Aims: Serum 25-hydroxyvitamin D (25(OH)D) comprises 25(OH)D3 and 25(OH)D2. Although sex differences in 25(OH)D levels have been reported, it remains unclear whether the difference lies profiles of 25(OH)D. We determined serum 25(OH)D3, 25(OH)D2, 3-epi-25-hydroxyvitamin D3 (3-epi-25(OH)D3), (24R)-24,25-dihydroxyvitamin (24,25(OH)2D3) measured by LC-MS/MS healthy adults not consuming...

The main aim of the study was to determine the influence of genetic factors on the serum 25-hydroxyvitamin D response to vitamin D supplementation. The main outcome measure was an increase in serum 25-hydroxyvitamin D after vitamin D supplementation. The patients are part of a randomized controlled trial in individuals with prediabetes assigned to 20 000 IU of vitamin D3 per week or placebo for...