(sourced from www.veritas.com)
Data suggests that a diet rich in selenium protects against cancers of the stomach, breast, esophagus, lung, prostate, colon, and rectum.
According to Dr. Harold Foster, death rates in the USA for cancer are lower when blood selenium levels are high. One important study found that a high blood level of selenium is associated with a 4-5-fold decrease in the risk of prostate cancer.
Scientists at Stanford University studied 52 men who had prostate cancer and compared them to 96 men who didn’t.
One surprising finding was that blood levels of selenium generally decreased with age. It is well known that the risk of prostate cancer increases dramatically as one ages.
Those who have studied geographical differences have seen that in low-selenium regions, higher death rates occurred from malignant lymphomas and cancers of the tongue, esophagus, stomach, colon, rectum, liver, pancreas, larynx, lung, kidneys and bladder.
In addition, cancer patients with low selenium levels tend to have a wider spread of the disease, more recurrences and die sooner.
In a China study Dr. Shu-Yu Yu classified the regions as high-selenium, medium-selenium, and low-selenium.
They then compared death rates from cancer to the selenium rates and found there was an exact correlation. In the low-selenium classification, three times as many people died from cancer as in the high-selenium classification.
Selenium, especially when used in conjunction with vitamin C, vitamin E and beta-carotene, works to block chemical reactions that create free radicals in the body (which can damage DNA and cause degenerative change in cells, leading to cancer).
Selenium also binds strongly with mercury, protecting us from its damaging effects.
Selenium helps stop damaged DNA molecules from reproducing, meaning it acts to prevent tumors from developing. “It contributes towards the death of cancerous and pre-cancer cells.
Their death appears to occur before they replicate, thus helping stop cancer before it gets started,” says Dr. James Howenstine in A Physician’s Guide to Natural Health Products That Work.
Epidemiologic studies suggest that zinc deficiency may be associated with increased risk of cancer. Zinc supplementation is associated with decreased oxidative stress and improved immune function, which may be among the possible mechanisms for its cancer preventive activity.
Zinc is essential for health. It’s needed for the enzymes that regulate cell division, growth, wound healing, and proper functioning of the immune system.
Zinc is an essential co-factor in a variety of cellular processes including DNA synthesis, behavioral responses, reproduction, bone formation, growth and wound healing.
Zinc is a component of insulin and it plays a major role in the efficiency of most of the functions of the body.
Zinc is necessary for the free-radical quenching activity of superoxide dismutase (SOD), a powerful antioxidant enzyme that breaks down the free-radical superoxide to form hydrogen peroxide.
Zinc is required for the proper function of T-lymphocytes.
The mineral also plays a role in acuity of taste and smell. And zinc is required for proper functioning of genetics, immunity, formation of red blood cells, organ, muscle and bone function, cell membrane stability, cell growth, division, differentiation and genetics. Importantly, zinc is vital for the metabolism of vitamin A.
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 MAY 19, 1931, Dr. P. Schrumpf-Pierron presented a paper entitled “On the Cause Of the Rarity of Cancer in Egypt,” which was printed in theBulletin of the Academy of Medicine, and the Bulletin of the French Association for the Study of Cancer in July, 1931.
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 Foster HD. “Landscapes of Longevity: The Calcium-Selenium-Mercury Connection in Cancer and Heart Disease,” Medical Hypothesis, Vol. 48, pp 361-366, 1997
 Foster HD. “Landscapes of Longevity: The Calcium-Selenium-Mercury Connection in Cancer and Heart Disease,” Medical Hypothesis, Vol. 48, pp 361-366, 1997.
 Prasad AS, Kucuk O. Zinc in cancer prevention. Department of Medicine (Division of Hematology-Oncology), Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine Detroit, MI 48201, USA. Cancer Metastasis Rev. 2002;21(3-4):291-5.