[Vitamin D supply among healthy blood donors in Vas County, Hungary]

There is growing evidence showing the importance of adequate vitamin D supply for preserving health.

The aim of the study was to evaluate the vitamin D supply among healthy blood donors and healthy elderly subjects in County Vas, Hungary.

Serum 25-hydroxyvitamin D, intact parathyroid hormone, calcium and albumin (Cobas, Modular, Roche), as well as serum alfa-2-globulin concentrations (Gelelfo, Interlab) were determined in 178 serum samples (68 men, 110 women, 41 were taking oral contraceptives). The results were analysed according to sex and age (younger and older than 43 years), and the impact of oral contraceptive use was also taken into consideration.

Deficiency and insufficiency in vitamin D levels were detected in 9.6% and 32% of the studied subjects, respectively, whereas sufficient vitamin D levels were present in 58.4% of the subjects. 63% of the older and 41.2% of the younger group had suboptimal vitamin-D supply (p < 0.01). In women taking oral contraceptives serum 25-hydroxyvitamin D and alfa-2-globulin levels were significantly higher, whereas serum albumin and calcium levels were lower than in the control group. There was no difference in serum intact parathyroid hormone concentration between oral contraceptive users and non-users.

The occurrence of suboptimal vitamin D supply is significant, although less frequent than that in literature reports. In women taking oral contraceptives, serum 25-hydroxyvitamin D levels were higher, but serum intact parathyroid hormone concentrations were not decreased suggesting that the increased 25-hydroxyvitamin D levels may be the consequence of oestrogen-induced alterations of serum protein fractions.