Phosphate (serum)
DEPhosphat (Serum)
Serum phosphate measures the inorganic phosphate floating in your blood. Its level reflects a balance between what your gut absorbs, what your kidneys hold onto, and what moves in and out of bone and cells. Three hormones run the show: parathyroid hormone (PTH), fibroblast growth factor 23 (FGF-23), and active vitamin D (calcitriol). High phosphate matters most in chronic kidney disease, where the kidneys cannot clear it, leading to overactive parathyroid glands, calcified blood vessels, and higher heart-related death. Even within the 'normal' range, higher phosphate in healthy adults has been independently tied to a thickened heart wall, stiffer arteries, and earlier death in large studies. Low phosphate can show up with refeeding syndrome, vitamin D deficiency, or too much FGF-23, and it saps your ATP (cellular energy), red-blood-cell function, and bone mineralization.
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Sources
- Onufrak SJ, Bellasi A, Shaw LJ, Herzog CA, Cardarelli F, Wilson PW, et al.. (2008). Phosphorus levels are associated with subclinical atherosclerosis in the general population. *Atherosclerosis*doi:10.1016/j.atherosclerosis.2007.11.004
- Giachelli CM. (2009). The emerging role of phosphate in vascular calcification. *Kidney International*doi:10.1038/ki.2008.644