Selenium: an important trace mineral
I won’t spend too much time discussing the common attributes of selenium as I’m sure you already know what a vitally important trace mineral it is, especially these days. Here are some facts you might not know:
Vitamin E and selenium interact to provide strong protection against oxidative damage to the liver. Vitamins C and E, as a team, produce an antioxidant effect that is far greater than any one individual antioxidant, and they each help to protect the other from the onslaught of free-radicals. Selenium and Vitamin A work together to help prevent cancer.1
Selenium also interacts with glutathione (GSH), which is a vital component in the production of glutathione peroxidase, an enzyme which is essential for life. The liver can only survive for about 3 days without the action of GSH, hence, we need all the essential supportive components of GSH activity, and Selenium is a key component. A huge percentage of people are deficient in selenium.
Though selenium is one of the most important trace minerals to help avoid certain life threatening diseases, it is also commonly deficient in many Americans, perhaps in part because large parts of the USA have selenium deficient soils. Further one study revealed that organically grown produce averaged over 300% more selenium in it than commercially grown food. If the findings in this study hold true all over the US, then it would be likely that the only people who had adequate selenium would only be those who eat organically grown food.2
Sources of selenium include nuts, grains, eggs, dairy and meats. Brazil nuts are exceptionally high in selenium with a single ounce providing many times the daily recommended value.
Selenium, as you probably already know, has been shown to have the properties needed to stimulate the immune system, protect the body against peroxide metabolites, radiation and free radicals, detoxify the body of environmental carcinogens, and to protect the liver. Selenium deficiency has been associated with AIDS, cancer, arthritis, Crohn’s disease, anemia, MS, asthma, low sperm counts, as well as other diseases and conditions.3
Even small doses of selenium can significantly enhance the cancer-fighting activity of Natural Killer cells in laboratory animals.4 Selenium is also essential for glutathione activity and helps protect the liver, kidneys, and pancreas from damage. Selenium appears to have a cancer-protective activity in addition to its antioxidant capacity in lipid metabolism.5 It helps prevent heart disease and cancer and protects the heart, lungs, liver, and blood cells from free radical damage. It is also known to help detoxify chemical carcinogens.6 It can reduce or prevent damage to the body from heavy metals.
High dosages of selenium, which are the equivalent of 54 mg/day in humans, produce an 83-90% reduction in the rate of tumor growth in mice.7
In fact, cancer mortality has been shown to be greater in areas where the selenium content of soil is low.8,9,10,11
There is a significant inverse correlation of cancer mortality of the breast, ovary, lung and leukemia related to selenium intake in humans.12
Studies have revealed that maximum reduction in tumor frequency occurs when supplemental selenium is provided throughout life.13
It appears that selenium has the ability to buffer heavy metals and chemotherapeutic drugs, however, these toxic substances can also inactivate or use up the body’s supply.
Is there one form that is better than another? You better believe it. Remember what I said about Vitamin B 12? (See my blog: The Second Most Common Vitamin Deficiency.) The same is true with selenium. In fact, some supplemental forms of selenium are highly toxic and the FDA had to limit the amounts used. My studies have shown that the safest form also happens to be the most bioavailable. It is L-selenomethionine which is the organic form of selenium.
1 Vitamins and Minerals in the Prevention and Treatment of Cancer, by Maryce M. Jacobs, pg. 105.
2 Smith, B. L. “Organic Foods vs. Supermarket Foods; Element Levels.” Journal of Applied Nutrition, 1993; Vol. 45, No. 1, pg. 35-39. Also see: http://journeytoforever.org/farm_library/bobsmith.html
3 Schrauzer, G.N. “Selenium for the Cancer Patient. Adjuvant Nutrition in Cancer Treatment Symposium, Tampa, Florida (Sept. 29, 1995).
4 Petrie, H.T. Differential Regulation of Lymphocyte Functional Activities by Selenium. (University of Nebraska Medical Center, 1988).
5 Iiip, C., and Sinha, D., Carcinogenesis, vol.2, no.5, p.435, 1981.
6 Vitamins and Minerals in the Prevention and Treatment of Cancer, pg. 101.
7 Watrach, AM, et al., Cancer Letters, vol. 25, p.41, 1984.
8 Shamberger, R.J. and Frost, D.V., Possible protective effect of selenium against human cancer, Can. Med. Assn. J., 104, 82, 1969.
9 Shamberger, R.J., Relationship of selenium to cancer. I. Inhibitory effect of selenium on carcinogenesis, J. Natl. Cancer Inst., 44, 932, 1970.
10 Schrauzer, G. N., White, D.A., and Schneider, C.J., Cancer mortality correlation studies. IV. Associations with Dietary intakes and blood levels of certain trace elements, notable Se-antagonists, Bioinorg. Chem., 7, 35, 1977.
11 Yu, S.Y., Chu, Y.J., Gong,X.L., Hou, C., Li, W.G., Gong, H.M., and Xie, J.R., Regional variation of cancer mortality incidence and its relation to selenium levels in China, Biol. Trace Elem. Res., 7, 21, 1985.
12 Schrauzer, G.N., White, D.A., and Schneider, C.J., Cancer mortality correlation studies. IV. Associations with dietary intakes and blood levels of certain trace elements, notable Se-antagonists, Bioinorg. Chem., 7, 35, 1977.
13 Vitamins and Minerals in the Prevention and Treatment of Cancer, by Maryce M. Jacobs, pg. 104.
For more information on selenium visit: http://americannutritionassociation.org/newsletter/what-selenium