25-Hydroxyvitamin D is the major circulating form of vitamin D. It occurs in two forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol), and is the precursor of the active form (1,25-dihydroxyvitamin D).
Because of its long half-life, measurement of total 25-Hydroxyvitamin D (D2 plus D3) provides the best assessment of patient vitamin D status and includes vitamin D derived from diet, supplements and exposure to UVB light, such as sunlight.
Vitamin D is best known for its role in calcium and bone metabolism, but emerging research indicates that low levels of vitamin D may be associated with increased risk of some cancers, type 2 diabetes, multiple sclerosis, cardiovascular disease, rheumatoid arthritis, depression, Alzheimer’s disease, infections, preeclampsia, cesarean deliveries and neurocognitive dysfunction.
Vitamin D regulates the expression of a vast array of genes in tissues including immune cells, the vasculature, muscle and reproductive organs. Vitamin D insufficiency is common and deficiency can have adverse health effects at any stage of life.
Many testing methods do not differentiate between the two forms of vitamin D, and only total concentrations are reported. This LC/MS QQQ method is sensitive and specific for both vitamin D2 and D3, and each form is measured and reported independently.
THIS IS THE ONLY FINGER PRICK TEST I KNOW OF THAT LOOKS AT ALL 3 MARKERS OF VITAMIN D – THE OTHERS ONLY LOOK AT ONE.
25-Hydroxyvitamin D Total
You also have the option of scheduling a test interpretation consultation. We recommend scheduling at least a 15-minute test interpretation consultation.