This section is compiled by Frank M. Painter, D.C. Send all comments or additions to:
Frankp@chiro.org
If there are terms in these articles you don't understand, you
can get a definition from the Merriam Webster Medical Dictionary. If you want information about a specific disease, you can access the Merck Manual. You can also search Pub Med for more abstracts on this topic.
Selenium is needed to activate a number of hormones produced by the thyroid gland. It also activates an antioxidant enzyme called glutathione peroxidase, which may help protect the body from cancer, and has been shown to induce "apoptosis" (programmed cell death) in cancer cells. Selenium also plays a vital role in the functioning of the immune system. Studies have found that selenium supplementation stimulates the activity of white blood cells. It also enhances the effect of vitamin E, one of three vitamins that act as antioxidants.
Selenium Articles
What is Selenium?
A nice review by students from the University of North Carolina School of Pharmacy
Selenium Biochemistry and Cancer: A Review of the Literature
Alternative Medicine Review 2004 (Sep); 9 (3): 239-258 ~ FULL TEXT
Animal data, epidemiological data, and intervention trials have shown a clear role for selenium compounds in both prevention of specific cancers and antitumorigenic effects in post-initiation phases of cancer.
Selenium Monograph
Alternative Medicine Review 2003 (Feb); 8 (1): 63–71 ~ FULL TEXT
This Adobe Acrobat article (67KB) states: The connection between selenium and cancer was originally demonstrated by correlation studies relating selenium levels in crops and cancer mortality rates. Broghamer reported that "Lower selenium levels in patients with carcinoma are likely to be associated with (1) distant metastisis; (2) multiple primary tumors; (3) multiple recurrences; and (4) short survival times."
Selenium: Antioxidant & Cancer Quencher
The mineral selenium has been gaining household recognition and respect in recent years by virtue of its addition to the list of nutritional antioxidants--substances that offer protection against our most dreaded diseases and aging. Indeed, selenium, as a component of several enzymes, does help rid the body of destructive oxidation products.
Dietary Antioxidant Health and Exercise
50th Annual meeting of the American College of Sports Medicine
San Francisco, USA May 2003
Professor Malcolm Jackson, from Liverpool University's department of medicine in the UK, presented data on the ability of subjects to rid themselves of a flu virus, with and without selenium supplementation. Subjects who supplemented with selenium (2 to 3 times the RNI) were able to rid their bodies of the virus significantly faster than the non-supplemented subjects. This study has many important implications. In addition to selenium's role in glutathione peroxidase metabolism, it has now been shown that selenium is also vital for optimal functioning of the immune system. These findings have broad-based implications and indicate that the current RNI for selenium is not high enough and may require revision. (This full abstract is no longer available online).
Selenium Stops Flu Mutations
Because flu virus mutations create new virus strains each year, it becomes virtually impossible for the body's immune system to develop a permanent defense. However, taking adequate amounts of selenium can prevent those mutations from occurring. Melinda A. Beck, Ph.D., a virologist at the University of North Carolina, Chapel Hill, and her colleagues exposed two groups of laboratory mice to a relatively mild flu virus strain called influenza A Bangkok, which also infects people. Flu viruses infecting selenium-deficient mice developed 29 mutations, which led to greater virulence. In contrast, selenium-replete mice experienced no mutations in the infecting virus and had milder symptoms.
Effects of Selenium Supplementation for Cancer Prevention in Patients with Carcinoma of the Skin
JAMA 1996 (Dec 25); 276 (24): 1957–1963
Selenium treatment did not protect against development of basal or squamous cell carcinomas of the skin. However, results from secondary end-point analyses support the hypothesis that supplemental selenium may reduce the incidence of, and mortality from, carcinomas of several sites.
Nutritional Aspects of Prostate Cancer: A Review
Can J Urol 2000 (Feb); 7 (1): 927–935
Incidence rates for prostate cancer vary according to diet and lifestyle. Several double-blind placebo-controlled clinical trials have shown that supplementation with selenium reduces cancer incidence. Inhibitory effects on the growth of in vitro prostate cancer cell lines have been observed with the administration of soy isoflavones, lycopenes from tomatoes, and vitamin D.
The Effect of Dietary Levels of Selenium on Radiation Resistance and Radiation–induced Carcinogenesis
Nutrition Research 1996; 16 (3): 505–516
A long–term experiment in 400 rats exposed to radiation following the Chernobyl pattern showed that a selenium–enriched diet started after exposure caused a longer average lifespan and a 1.5 – 3.5 fold decrease of leukaemias and other malignancies, e.g. breast, thyroid and lung cancers, etc., at late times. Selenium was first demonstrated to provide protection against late effects which is equivalent to a whole–body dose reduction by 1.4 Sv (140 rem).
Thanks to
Pub Med
for their quality MEDLINE search tool.
