Dietary supplements and cancer prevention: " there is now evidence that high doses of some supplements increase cancer risk"

http://www.ncbi.nlm.nih.gov/pubmed/22534785

J Natl Cancer Inst. 2012 May 16;104(10):732-9. Epub 2012 Apr 25.

Dietary supplements and cancer prevention: balancing potential benefits against proven harms.

Martínez ME, Jacobs ET, Baron JA, Marshall JR, Byers T.

Source

Moores UCSD Cancer Center, 3855 Health Sciences Dr, No. 0901, La Jolla, CA 92093-0901. e8martinez@ucsd.edu.

Abstract

Nutritional supplementation is now a multibillion-dollar industry, and about half of all US adults take supplements. Supplement use is fueled in part by the belief that nutritional supplements can ward off chronic disease, including cancer, although several expert committees and organizations have concluded that there is little to no scientific evidence that supplements reduce cancer risk. To the contrary, there is now evidence that high doses of some supplements increase cancer risk. Despite this evidence, marketing claims by the supplement industry continue to imply anticancer benefits. Insufficient government regulation of the marketing of dietary supplement products may continue to result in unsound advice to consumers. Both the scientific community and government regulators need to provide clear guidance to the public about the use of dietary supplements to lower cancer risk.