Vitamin D Deficiency and Prostate Biopsy
Arecent study suggested that vitamin D deficiencies could be a predictor of prostate cancer diagnoses and aggressiveness, especially among African American men.
Researchers obtained serum vitamin D levels from 667 men aged 40-79 having prostate biopsies at Chicago urology clinics. African American men with vitamin D deficiencies were nearly 5 times more likely to have aggressive prostate cancer. European American men with vitamin D deficiencies were nearly 4 times more likely to have aggressive prostate cancer.
For most people, approximately 90% of vitamin D comes from sunshine. The liver converts solar UV radiation into the form of vitamin D typically measured in blood serum. Other sources of vitamin D include supplements, dairy, mushrooms, eggs and fatty fish such as salmon.
Previous studies have linked vitamin D deficiency and prostate cancer, but further study is needed to explore the relationship and the potential to use vitamin D deficiency as a biomarker for advanced prostate cancer.
Dr. Catalona was a co-author of this study.
Murphy, A. et al. Vitamin D Deficiency Predicts Prostate Biopsy Outcomes. Clin Cancer Res. 2014; 20(9):2289-2299.
Selenium, Vitamin E, and Prostate Cancer
Researchers found that high dose supplementation with selenium and vitamin E can increase the risk of prostate cancer in men who have high levels of selenium before they begin taking the supplements.
Among men who had lower levels of baseline selenium (‹60th percentile), taking selenium supplements (200 mcg/day) with or without vitamin E supplements did not affect the risk of prostate cancer. However, in men with higher baseline selenium levels, selenium supplementation increased the risk of high-grade prostate cancer by 91%.
The researchers also found that taking vitamin E supplements (400 IU/day) without selenium did not affect prostate cancer risk in men with high selenium levels (≥40th percentile). In men with lower baseline selenium levels, vitamin E supplementation increased the overall risk of prostate cancer by 63%. The risk of high-grade prostate cancer was increased by 111% in this group.
Baseline selenium levels without supplementation were not associated with prostate cancer risk. The authors concluded that men over 55 years should avoid selenium or vitamin E supplementation at doses that exceed recommended dietary intakes.
The study examined 1,739 men with prostate cancer and 3,117 men in a randomly selected cohort using data from the Selenium and Vitamin E Cancer Prevention Trial (SELECT).
Kristal A. et al. Baseline Selenium Status and Effects of Selenium and Vitamin E Supplementation on Prostate Cancer Risk. J Natl Cancer Inst. 2014; 106(3): djt456 doi:10.1093/jnci/djt456