Vitamin D3 (25-OH)

Assessment of vitamin D status and definition of a normal circulating range of 25-hydroxyvitamin D.

Researchers reviewed the increasing importance of measuring circulating 25-hydroxyvitamin D (25[OH]D) for clinical diagnosis. They noted that 25(OH)D levels are linked to various health conditions, including cancer and autoimmune diseases. The study emphasized the need for standardized reference ranges and improved assay methods for accurate measurement.

Epidemiology of vitamin D in health and disease.

This review focused on the role of vitamin D in health and disease, highlighting its association with reduced risks of various conditions including bone fractures and autoimmune diseases. Researchers found significant vitamin D insufficiency, particularly in individuals with dark skin or living at high latitudes. The study emphasized the need for standardization of vitamin D assays due to disparities in measurement results.

Vitamin D in Cardiovascular Disease.

This study reviewed the relationship between vitamin D deficiency and cardiovascular disease. Researchers found that low levels of vitamin D are associated with increased inflammation and atherogenesis. However, they noted that the role of plasma 25-hydroxyvitamin D as a biomarker for future cardiovascular disease remains unclear.

Measurement of vitamin D and its metabolites (calcidiol and calcitriol) and their clinical significance.

Schmidt-Gayk H, et al. · Scandinavian journal of clinical and laboratory investigation. Supplementum · 1997

This study examined the significance of measuring plasma concentrations of 25-hydroxyvitamin D (25[OH]D) as a marker for vitamin D deficiency. Researchers found that low levels of 25(OH)D are common in Europe and North America during winter months, and supplementation is recommended for those below 50 nmol/L. They also noted that 1,25-dihydroxyvitamin D (calcitriol) levels depend on renal function and other factors.

The Vitamin D Standardization Program (VDSP) Manual for Retrospective Laboratory Standardization of Serum 25-Hydroxyvitamin D Data.

This paper introduced methodologies for the retrospective standardization of serum 25-hydroxyvitamin D data. Researchers described approaches to reanalyze banked samples to improve comparability of vitamin D measurements across studies, addressing variability in assay results.

Serum 25-hydroxyvitamin D levels in Finnish children aged 2 to 17 years.

Measurement of circulating 25-hydroxyvitamin D: A historical review.

Researchers reviewed the historical development of methods for measuring serum 25-hydroxyvitamin D. The study highlighted the introduction of liquid chromatography coupled to tandem mass spectrometry (LC/MS2) as a promising approach but noted the need for harmonization among different methods to ensure consistent results across laboratories.