This article appeared today in a post by NUTRAingredients.com:

“Higher blood levels of selenium may reduce the incidence of skin cancer by about 60 per cent, according to a new study from Dutch and Australian researchers.  Writing in Cancer Epidemiology, Biomarkers & Prevention, the researchers report that the mineral was associated with reduced risks of both basal cell carcinoma (BCC) and squamous cell carcinoma (SCC).”

The FDA states:  Selenium may reduce the risk of certain cancers. Some scientific evidence suggests that consumption of selenium may reduce the risk of certain forms of cancer. However, FDA has determined that this evidence is limited and not conclusive.

The Office of Dietary Supplements. part of NIH, states:

Selenium and cancer
Observational studies indicate that death from cancer, including lung, colorectal, and prostate cancers, is lower among people with higher blood levels or intake of selenium [1-7]. In addition, the incidence of nonmelanoma skin cancer is significantly higher in areas of the United States with low soil selenium content [4]. The effect of selenium supplementation on the recurrence of different types of skin cancers was studied in seven dermatology clinics in the U.S. from 1983 through the early 1990s. Taking a daily supplement containing 200 μg of selenium did not affect recurrence of skin cancer, but significantly reduced the occurrence and death from total cancers. The incidence of prostate cancer, colorectal cancer, and lung cancer was notably lower in the group given selenium supplements [8].

Research suggests that selenium affects cancer risk in two ways. As an anti-oxidant, selenium can help protect the body from damaging effects of free radicals. Selenium may also prevent or slow tumor growth. Certain breakdown products of selenium are believed to prevent tumor growth by enhancing immune cell activity and suppressing development of blood vessels to the tumor [9].

The latest research, as stated in the nutraingredients article, was conducted at Queensland Institute of Medical Research, the University of Queensland, and Maastricht University.

“Relatively high serum selenium concentrations are associated with an approximately 60 per cent decrease in subsequent tumour incidence of both BCC and SCC,” wrote the researchers, “whereas serum concentrations of carotenoids or alpha-tocopherol are not associated with later skin cancer incidence.”

The American Institute for Cancer Research has numerous articles about selenium and cancer. http://www.aicr.org/site/DocServer/ProstateMC.pdf?docID=1641

Sources:  www.nutraingredients.com;   http://ods.od.nih.gov/factsheets/selenium.asp;   www.aicr.org;

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2. Patterson BH and Levander OA. Naturally occurring selenium compounds in cancer chemoprevention trials: A workshop summary. Cancer Epidemiol Biomarkers Prev 1997;6:63-9. [PubMed abstract]
3. Knekt P, Marniemi J, Teppo L, Heliovaara M, Aromaa A. Is low selenium status a risk factor for lung cancer? Am J Epidemiol 1998;148:975-82. [PubMed abstract]
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