There is a high prevalence of vitamin D deficiency worldwide, but how to define vitamin D deficiency is controversial. Currently, the plasma concentration of total 25-hydroxyvitamin D [25(OH)D] is considered an indicator of vitamin D status. The free hormone hypothesis states that protein-bound hormones are inactive while unbound hormones are free to exert biological activity. The majority of c...

Vitamin D deficiency is an emerging health concern around the world, highly prevalent in south Asian population, despite abundant sunlight. In Pakistan, all age groups are vulnerable to Vitamin D deficiency including pregnant women. This systematic review aimed to determine the pattern of Vitamin D deficiency among Pakistani pregnant women as well as exploring the causes and possible interventi...

BACKGROUND The aim of this study was to evaluate the association of maternal serum 25-hydroxyvitamin D, paraoxonase 1, and neutrophil-to-lymphocyte ratio in women having early spontaneous preterm birth without clinical chorioamnionitis. MATERIAL AND METHODS This study was prospectively administered in women referred to our obstetrics service with preterm labor that resulted in preterm birth (n=...

The present study was conducted to assess the relationship between metabolic syndrome and metabolic syndrome score (MSS) and serum vitamin D levels in adults aged 20 or older (n = 5,483) using 2012 Korean National Health and Nutrition Examination Survey data, which represents national data in Korea. Key study results were as follows: First, serum 25-hydroxyvitamin D [25(OH)D] levels decreased s...

The utility of 4-(4-nitrophenyl)-1,2,4-triazoline-3,5-dione (NPTAD) as a derivatization reagent in the analysis of 25-hydroxyvitamin D3 [25(OH)D3] using liquid chromatography/electron capture atmospheric pressure chemical ionization-mass spectrometry (LC/ECAPCI-MS) was examined. The derivatives of 25(OH)D3 with NPTAD underwent electron capture in the APCI source in the negative-ion mode and pro...

Human trophoblastic cells (T3M-3) metabolized 25-hydroxyvitamin D3 into two more polar metabolites during in vitro incubations. A two-step high pressure liquid chromatography system revealed two unique elution positions of those trophoblastic cell-derived metabolites that exactly co-migrated with the elution positions of 5(Z)-19-nor-10-oxo-25-hydroxyvitamin D3 and 5(E)-19-nor-10-oxo-25-hydroxyv...

Vitamin D is a hormone synthesized in the skin in the presence of sunlight. Like other hormones, vitamin D plays a role in a wide range of processes in the body. Here we review the possible role of vitamin D in nociceptive and inflammatory pain. In observational studies, low vitamin D levels have been associated with increased pain and higher opioid doses. Recent interventional studies have sho...

The need, safety, and effectiveness of vitamin D supplementation during pregnancy remain controversial. In this randomized, controlled trial, women with a singleton pregnancy at 12 to 16 weeks' gestation received 400, 2000, or 4000 IU of vitamin D(3) per day until delivery. The primary outcome was maternal/neonatal circulating 25-hydroxyvitamin D [25(OH)D] concentration at delivery, with second...

BACKGROUND The vitamin D-endocrine system is thought to play a role in physiologic processes that range from mineral metabolism to immune function. Serum 25-hydroxyvitamin D [25(OH)D] is the accepted biomarker for vitamin D status. Skin color is a key determinant of circulating 25(OH)D concentrations, and genes responsible for melanin content have been shown to be under strong evolutionary sele...

1. The plasma disappearance of 3H-labelled 25-hydroxyvitamin D3 (25(OH)D3) was studied in healthy volunteers on normal and high-fibre diets, using 3H-labelled tracer doses given intravenously. 2. The mean (+/- SEM) plasma half-life in the high-fibre-diet group was 19.2 +/- 1.7 d, which was significantly shorter than in the group on normal diets (27.5 +/- 2.1 d, P less than 0.01). 3. This findin...