Plasma Levels of Vitamin D Metabolites of Healthy Subjects in Akita, Japan

Abstract

Plasma levels of 25-hydroxyvitamin D_3 (25-OH-D_3) and 1α,25-dihydroxy-vitamin D_3 [1,25-(0H)_2-D_3] of healthy subjects in Akita were determined to investigate the antirachitic activity of sun light and the nutritional problems of vitamin D_3. The results are summarized in the following: (1) Plasma levels of 25-OH-D_3 of healthy subjects in Akita were 23.2±8.1 (M±SD)ng/ml, and these in summer were higher than those in winter. It showed the age variation that the levels in the forties and fifties were significantly higher than those in the subjects of under twenties. (2) Plasma levels of 1,25-(OH)_2-D_3 of healthy subjects in Akita were 49.0±17.9pg/ml, which did not show significant difference among sexes, seasons and generation. (3) The plasma levels of 25-OH-D_3 and 1,25-(OH)_2-D_3 in Akita were not significantly different from the respective data in Hanshin area.