Written by Jessica Patella, ND. High levels of selenium have been shown to decrease risk of bladder cancer by 39%.
Worldwide, bladder cancer is one of the most common forms of cancer (1). In the United States, approximately 70,530 men and women will be diagnosed and approximately 14,680 individuals will die from bladder cancer this year (2). In terms of medical expenditures, bladder cancer is the fifth most expensive cancer, costing almost 3.7 billion dollars in 2001 (3). Is there something natural that could have a protective effect against bladder cancer? Recent research shows high intakes of selenium may be beneficial to reduce the risk of bladder cancer (1).
Minimal research has been conducted looking at the correlation between bladder cancer and selenium intake. A recent meta-analysis, which combines the results of several studies, was conducted to determine if there is an overall reduction in the risk of bladder cancer with higher intakes of selenium (1). The meta-analysis included seven studies with a total of 17,339 participants (1). Four of the studies were conducted in the United States and three in Northern Europe. When all seven studies were analyzed by gender, only women showed a significant decrease in the risk of bladder cancer with selenium (odds ratio=0.55; 95% CI, 032-0.95) (1). However, when combining the results from all seven studies and not accounting for gender, an overall 39% decrease risk of bladder cancer (p=0.018) was associated with higher levels of selenium. (1).
High levels of selenium include either concentrations of selenium in totals of 0.9 micrograms/g and higher, or serum levels of 100 microgram/L and higher (1). It is still unclear how selenium works, although it is possible the reduction in cancer risk is due to antioxidant properties (1).
In conclusion, this meta-analysis shows higher levels of selenium are associated with a lower risk of bladder cancer (1). A randomized, controlled trail is needed to obtain a better understanding of this correlation.
Source: Amaral, André FS, et al. “Selenium and bladder cancer risk: a meta-analysis.” Cancer Epidemiology and Prevention Biomarkers (2010): 1055-9965.
© 2010 American Association for Cancer Research
Posted October 22, 2010.
References:
- Amaral, et al. Selenium and Bladder Cancer Risk: A Meta-analysis.” In the August 2010 issue of American Association for Cancer Research. Cancer Epidemiol Biomarkers Prev; 19(9); 2407-15. Copyright AACR.
- Cancer of the Urinary Bladder. National Institute of Cancer.
- Botteman, et al. The health economics of bladder cancer: a comprehensive review of the published literature. Pharmacoeconomics. 2003;21(18):1315-30.
- Dietary Supplement Fact Sheet: Selenium. National Institute of Health.
