High Selenium Blood Levels Decrease in the Potential of Colon Cancer
By Joesph Walker, MD.
It looks like we have another week chock-full of nutrition news. In a study out this week published in the Journal of the National Cancer Institute, researchers from the University of Arizona pooled the data from three completed clinical trials to determine the effects of nutritional intervention on cancer recurrence in patients who had undergone colon cancer surgery. After adjusting for other factors, it was found that those individuals with the highest selenium blood levels had a 44% reduction in cancer colon recurrence compared with those individuals with the lowest blood levels. The authors of the study indicated that it is possible that selenium supplementation could, indeed, protect against colon cancer, although they further indicated that it is still not known what form of selenium and what amount would be protective.
My recommendation for adequate daily selenium intake is well-known in my newsletters. I have written about this repeatedly over the past few years. I have also made mention of an ongoing nationwide study known as the Selenium and Vitamin E Chemoprevention Trial (SELECT), involving the use of selenium and vitamin E in prostate cancer prevention. In the editorial accompanying the study in the Journal of the National Cancer Institute, it was noted that there are already more than 35,000 men enrolled in this study. Unfortunately, it's estimated that the results of the selenium/vitamin E cancer study will not be known for at least six to eight years. From a scientific standpoint, I suppose it would be important to have definitive, undeniable proof that a particular treatment is useful and safe, but as we learned from the recent Vioxx (and I suspect, soon to be other COX2 inhibitors) disaster, even studying a few thousand patients for two or three years cannot ensure safety. It is clear, however, that selenium taken in its recommended doses of 200 to 600 mcg a day is completely and totally safe, as it has been used by millions of individuals in this country for over two decades.
Selenium's Effect on Prostate Cancer
In terms of selenium's effectiveness, in prior newsletters, I had mentioned two studies on selenium that I will now briefly review again. One study published in the Journal of the American Medical Association (JAMA) and involving over 1,300 patients showed that in a double-blinded study against placebo, 200 mcg of selenomethionine daily reduced overall cancer incidence by 37 % and reduced cancer mortality by 50%. A subsequent study published in the Journal of the National Cancer Institute from 1998 showed that in over 30,000 men tested for selenium levels, those men with the highest levels reduced their risks of malignant forms of prostate cancer by approximately two thirds. My question is, with a nutrient that is known to be completely safe, as well as one that could potentially reduce the risk of cancer by significant margins, why wouldn't every single doctor be recommending it to his/her patients? The unfortunate answer is that most doctors are not aware of this information.
Alzheimer's prevention - antioxidant quercetin, found in apples
In a second newsworthy study just published in an agricultural and food chemistry journal, researchers from Cornell University, citing the old adage "an apple a day really does keep the doctor away," apparently proved it in an animal study. Rat brain cells exposed to the antioxidant quercetin (found in apples) appeared to inhibit potential damage to brains from chemicals producing free-radicals. The brain cells were exposed to hydrogen peroxide, which is felt to mimic the type of oxidative damage that may occur in Alzheimer's disease. Those brain cells pretreated with quercetin had significantly less damage compared to those cells treated with only vitamin C or no antioxidants. The lead author of the study indicated that fresh apples have some of the highest levels of quercetin compared to other fruits and vegetables, and may be one of the best food choices for fighting Alzheimer's.
For the last eight years, we have been including a daily dose of 200 mcg of the organic selenomethionine form of selenium in all of our Synergy multi-vitamins and many other nutraceuticals, including OcuPower®, ArthriPower®, NeuroPower®, and NeuroLift® from Nutraceutical Sciences Institute (NSI). Compare this to the typical mass-marketed multi-vitamins, which contain only 20 mcg, or 1/10th the optimal dose of the inorganic form of selenium that is the least effective and cheapest. Additionally, we use significant amounts of the antioxidant quercetin in these products, which prior studies have shown to potentially reduce the risk of stroke, heart disease, and other degenerative disorders of aging. Check the label of your current multi-vitamin. You may be very disappointed, as most do not have quercetin and/or the level is miniscule. The typical diet supplies just a few milligrams per day of quercetin, whereas NSI recommends 50 - 200 mg per day in supplemental form. So whether you take NSI's Synergy Once-a-Day, Synergy Max, or one of NSI's other nutraceuticals, you can be assured that you are getting excellent doses and forms of these two very important nutrients, along with a host of other antioxidants, vitamins, minerals, standardized herbs, and phytonutrients. If for some reason you cannot take a multi-vitamin, NSI provides an excellent value for selenium in the correct form and dosage as a standalone product. NSI also offers quercetin with vitamin C in both ascorbic acid and Ester-C forms. Vitamin C is very synergistic with quercetin and provides numerous benefits for immune and cardiovascular function.
Selenium and Colorectal Adenoma: Results of a Pooled Analysis.
Journal of Natl Cancer Inst. 2004 Nov 17;96(22):1669-1675.
Can Selenium Prevent Colorectal Cancer? A Signpost From Epidemiology.
Journal of Natl Cancer Inst. 2004 Nov 17;96(22):1645-1647. No abstract available.
Is there any role for prevention strategies for colorectal cancer other than population-based screening?
Bratisl Lek Listy. 2004;105(5-6):215-24.
Targeting multiple signaling pathways as a strategy for managing prostate cancer: multifocal signal modulation therapy.
Integr Cancer Therapy. 2004 Dec;3(4):349-80.
Dietary antioxidants and human cancer.
Integr Cancer Therapy. 2004 Dec;3(4):333-41.
Re: Science peels the onion of selenium effects on prostate carcinogenesis.
Journal of Natl Cancer Inst. 2004 Nov 3;96(21):1640. No abstract available.
DNA methylation, cancer susceptibility, and nutrient interactions.
Experimental Biological Medicine (Maywood). 2004 Nov;229(10):988-95.
The use of high-selenium yeast to raise selenium status: how does it measure up?
British Journal of Nutrition. 2004 Oct;92(4):557-73.
The Link between Selenium and Chemoprevention: A Case for Selenoproteins.
Journal of Nutrition. 2004 Nov;134(11):2899-902.
Dietary intervention in prostate cancer patients: PSA response in a randomized double-blind placebo-controlled study.
International Journal of Cancer. 2004 Oct 21;
Nutrition and cancer: A review of the evidence for an anti-cancer diet.
Nutrition J. 2004 Oct 20;3(1):19.
Antioxidant supplements for preventing gastrointestinal cancers.
Cochrane Database Systematic Review. 2004 Oct 18;(4):CD004183.
The beneficial effect of selenium against induction of squamous cell carcinoma of the tongue in rabbits
Kulak Burun Bogaz Ihtis Derg. 2003 Oct;11(4):100-7. Turkish.
Methyl selenium-induced vascular endothelial apoptosis is executed by caspases and principally mediated by p38 MAPK pathway.
Nutrition Cancer. 2004;49(2):174-83.
Selenomethionine stimulates MAPK (ERK) phosphorylation, protein oxidation, and DNA synthesis in gastric cancer cells.
Nutrition Cancer. 2004;49(2):184-90.
A Little Selenium Goes a Long Way?
55 micrograms per day for adults, according to the U.S. Recommended Daily Allowance. The main dietary sources of selenium in the U.S. are grains.
Meats, seafood, grains, and some nuts (such as Brazil nuts) are good sources of selenium. Foods grown in areas with selenium-rich soils have higher levels of the mineral, but selenium soil deficiency is rare in the U.S.
Selenium Deficiency Increases Severity of Flu Virus in Mice
If young mice are given a diet deficient in selenium and subsequently exposed to a human influenza virus, they get a more severe case of flu than animals fed adequate amounts of this essential trace element.
That's the finding of a collaborative study by researchers at the University of North Carolina (UNC) in Chapel Hill; Nestle Research Center in Lausanne, Switzerland; and the Agricultural Research Service (ARS) in Beltsville, Md. And it follows the pattern seen in earlier studies with a lesser known virus. This indicates that a selenium deficiency can increase the virulence of a variety of viruses. - ARS is the U.S. Department of Agriculture's primary scientific research agency.
Selenium Shows A Decrease in Colon Cancer's Potential
Analysis published in the Journal of the National Cancer Institute, showed a progressive decrease in the likelihood of colon cancer recurring with increasing levels of selenium, with a 44-percent reduction for the highest compared with the lowest level. "Selenium supplementation could protect against colon cancer"?
Selenium and Colon Cancer Research
Follow peer reviewed jounals as they cover the lastest colon cancer and selenium research