Introduction: The supply of selenium (Se) varies widely in Germany. Therefore, a laboratory study was conducted in patients treated at a family doctor practice in Brandenburg, Germany, to determine whether there is a general Se deficiency in this area; specifically, whether Se concentrations differ with age, sex, or presence of cancer. Moreover, we tested the effects of a Se supplementation on whole blood Se levels (WBSL).
Methods: In 2006, WBSL were analyzed in 871 patients (496 females, 375 males, median age: 67 years). Of these, 143 (78 females, 65 males) had cancer and were in an aftercare situation. From 2006 to 2012, 317 patients (76 with tumors, 241 without tumors) received continuous Se supplementation with sodium selenite (300 µg per day) and annual WBSL measurements. WBSL were compared by Student's t test for paired and independent samples.
Results: The initial WBSL of all patients was 97.2 ± 20.7 µg/L (mean ± SD). WBSL did not differ with regard to age or sex, but patients with cancer had the lowest WBSL. Se supplementation increased mean WBSL in both patients with (to 128.5 µg/L) and without (to 119.52 µg/L) cancer ( P < .001).
Discussion: Patients with cancer displayed significantly lower WBSL than patients without cancer, indicating a negative effect of tumors on Se uptake, absorption, or metabolism. Significant influences of age or sex were not observed. Selenite supplementation efficiently improved WBSL to concentrations considered necessary for health benefits.
Keywords: patients with tumors; patients without tumors; selenium supplementation; sodium selenite; whole blood selenium levels.