Calcifediol Supplementation Toxicity
Vitamin D Supplementation: Concerns about Toxicity
Vitamin D (calciferol) is so essential to health that all vertebrates can produce this nutrient endogenously when the skin is exposed to ultraviolet light (Hoffmann, Senior, Mager 2015; Standing Committee et al. 1997). Vitamin D can also be obtained from fish and modern-day fortified food products. When exposed to sunlight, 7-dehydrocholesterol in the skin is converted to previtamin D3 (cholecalciferol) and then vitamin D3, which is then hydroxylated by liver enzymes to form 25-hydroxyvitamin D3 (25(OH)D3; calcifediol). The biologically active form is finally created when calcifediol is hydroxylated once more by a mitochondrial enzyme in the kidneys to form 1,25-dihydroxyvitamin D (1,25(OH)2D; calcitriol).
The two most common forms of dietary vitamin D supplementation are cholecalciferol and calcifediol, but the biological activity of the latter is 5 times that of the former (Standing Committee et al. 1997). The downstream effect of 1,25(OH)2D production is increased absorption and utilization of dietary calcium and phosphorus and increased plasma levels of these minerals. As calcium plasma levels rise, and to a lesser extent phosphorus plasma levels, the same kidney cells will reduce calcitriol production through a parathyroid hormone-dependent feedback loop. Deluca and colleagues (2011) have suggested that vitamin D toxicity is probably the result of high plasma concentrations of calcium and phosphorus,...
Vitamin D toxicity can only occur in healthy people through the excess consumption of fish oils or supplements, not through excess exposure to sunlight.
Since dietary and endogenous sources of vitamin D contribute to calcifediol serum concentrations, physicians interested in monitoring a patient's vitamin D status will quantify this marker (Standing Committee et al. 1997). The normal range for the general population varies depending on the geographic location, with sunnier locations having a higher range; however, a calcifediol concentration below 27.5 nmol/liter (11 ng/ml) in young children and infants represents vitamin D deficiency. The elderly represent another susceptible group and both plasma calcifediol and parathyroid hormone levels are checked for vitamin D deficiency. Current recommendations are for everyone to get sufficient exposure to sunlight, but when this is not possible, the diet should be supplemented with 200 international units (IU) per day for all ages up to…
Hence calcitonin has been found to reduce the turnover of bone and pain in Paget's disease patients. It is found as an injection: 200 units/ml administered intramuscularly or subcutaneously. Also available is intranasal spray: 200 units/activation (0.09 ml/puff) which is administered into the nostril. There are no adequate studies of calcitonin in pregnant women and nursing mothers. Calcitonin salmon helps treat osteoporosis and Paget's disease of bone but does not
Chronic Kidney Disease CKD, or Chronic Kidney Disease, refers to the impairment a person suffers in his/her kidneys, which may result in their reduced function, as time progresses. Chronic Kidney Disease is used as a replacement for previously held terms, such as the Chronic Renal Failure and Chronic Renal Insufficiency by the paediatric nephrology specialists. These terms were formerly used to describe the reduction of renal functions, whether to a large
Hypokalemia occurs when the blood plasma level of potassium is too low (below 3.5 mcg). This is the most common electrolyte imbalance. It effects cardiac conduction and function. Calcium Calcium is a cation that is stored in the bone, plasma and body cells. In plasma, it binds with albumin. It is well-known that calcium is necessary for healthy teeth and bones. However, it is also necessary for blood clotting, hormone secretion,
Education of Hemodialysis-Dependent Patients Concerning the Use of Phosphorus Binder in Lieu of Dialysis during Emergencies Clinical Leadership Theme: The clinical leadership competency/role and/or magnetism thread that is the framework for this project requires effective transformational leadership practices that can motivate all stakeholders to become educated concerning the use of phosphorus binders in lieu of dialysis (Cook, 2004). Patient: Hemodialysis-dependent patients Intervention: EDUCATE and train to use phosphorus binder Comparison: in lieu of no