Background. Vitamin D is an effective substance in the treatment of disorders of phosphorus-calcium homeostasis.
The biological activity of vitamin D2 and D3 may however differ. The objective of the investigation is to assess the
biological action of both vitamins in man and their possible differences.
Methods and Results. The group comprises two different subgroups of patients. The first is formed by 3 men,
mean age 69.2 years and 9 women mean age 70.8 years. The second one comprises 14 drug addicts (10 men mean
age 31.1 years and 4 women mean age 28.9 years). All patients were given for a period of two months 1300 IU
vitamin D2 and D3. The vitamin D values in blood were assessed using a kit estimating 25 hydroxyvitamin D produced
by Nichols Institute Diagnosis. Other laboratory indicators were assessed photometrically. The data were analyzed
by the paired t-test. No significant differences of mean 25 hydroxyvitamin D levels were found.
Conclusions. The results did not provide an answer to the different biological effectiveness of vitamins D2 and
D3 in man.
vitamin D2, vitamin D3, 25 hydroxyvitamin D, elderly people, drug addicts.