To the Editor: The Selenium and Vitamin E Cancer Prevention Trial (SELECT) by Dr Lippman and colleagues1 reported that selenium or vitamin E alone or in combination did not prevent prostate cancer. The negative results of this trial confirm the outcomes in the Nutritional Prevention of Cancer (NPC) Trial for those participants with the highest baseline plasma selenium concentration prior to supplementation with selenized yeast.2 The conclusion from both NPC and SELECT should be that daily selenium supplementation will not benefit all persons. Cancer risk reduction with selenium should be expected only in men with low or suboptimal levels prior to supplementation.
Rayman MP, Combs GF, Waters DJ. Selenium and Vitamin E Supplementation for Cancer Prevention. JAMA. 2009;301(18):1876-1877. doi:10.1001/jama.2009.625