[Vitamin C in medicine: "normal concentration" in serum].

Vitamin C functions in a human organism have been discussed. Connection with many diseases and its systemic deficiency has been emphasized. A review of current application of this vitamin in medicine has been made. Problems accompanying the use of reference sources of vitamin C "normal concentrations" in blood plasma have been characterised. 10 ranges of concentrations given by medical handbooks and textbooks have been compared in detail with 15 parallel ranges taken from scientific papers, paying attention to their significant discrepancies. Basing on source values, performing basic statistical calculations, a reliable mean range of vitamin C "normal concentrations" in blood plasma has been obtained: 36.1-79.4 mumol/l.