Selenium: a Powerful Anti-cancer Medicine
One of the most effective naturally occurring weapons against cancer is, like most healthy things, something many of us are not getting enough of. The mineral selenium has been shown in multiple studies to be an effective tool in warding off various types of cancer, including breast, esophageal, stomach, prostate, liver and bladder cancers. Not many people get the recommended dose of 200 micrograms a day. Most Americans only get between 60 and 100 micrograms of selenium daily from dietary sources, according to the Life Extension Foundation's Disease Prevention and Treatment. That means daily supplements might be worth considering.
Selenium was first used in conventional medicine as a treatment for dandruff, but our understanding of the mineral has come a long way since then. Today, research shows 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 helps stop damaged DNA molecules from reproducing. In other words, selenium 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.
Selenium makes chemotherapy safer, more effective
In addition to preventing the onset of the disease, selenium has also been shown to aid in slowing cancer's progression in patients that already have it. According to the Life Extension Foundation, the use of selenium during chemotherapy in combination with vitamin A and vitamin E can reduce the toxicity of chemotherapy drugs. The mineral also helps "enhance the effectiveness of chemo, radiation, and hyperthermia while minimizing damage to the patient's normal cells; thus making therapy more of a 'selective toxin,'" says Patrick Quillin in Beating Cancer with Nutrition.
A 1996 study by Dr. Larry Clark of the University of Arizona showed just how effective selenium can be in protecting against cancer. In the study of 1,300 older people, the occurrence of cancer among those who took 200 micrograms of selenium daily for about seven years was reduced by 42 percent compared to those given a placebo. Cancer deaths for those taking the selenium were cut almost in half, according to the study that was published in the Journal of the American Medical Association.
While the study concluded the mineral helped protect against all types of cancer, it had particularly powerful impacts on prostate, colorectal and lung cancers. Jean Carper, in Miracle Cures, called Dr. Clark's findings an "unprecedented cancer intervention study" that "bumped up the respectability of using supplements against cancer several notches."
Food sources of selenium
Although too much selenium can actually be toxic to the system, research indicates the majority of the population is not getting enough of the essential mineral. So, how can we up our intake of selenium and help our bodies fight cancer? The good news is there are some good dietary sources of selenium: Mushrooms, egg yolks, seafood, poultry and kidney, liver and muscle meats contain the mineral. Vegetables — garlic, onions, broccoli, asparagus, tomatoes and others — as well as whole grains and seeds can also be good sources of selenium.
However, because the amount of selenium in vegetables and grains depends on the selenium content in the soil in which they are grown, it can be hard for average consumers to know how much of the mineral they are actually getting in their diets. "The selenium content of food is largely dependent on the content of volcanic ash in the soil on which the food was grown, with higher volcanic ash content yielding higher selenium levels. Soil that is irrigated by seawater, such as much of California's cropland, also contains higher levels of selenium," says Sue Gebo in What's Left to Eat. Gebo adds that, in general, soil in the western United States is richer in selenium than soil in the eastern part of the country.
Accordingly, geography can have a significant impact on diet. In Antioxidants Against Cancer, author Ralph Moss PhD, says one theory for why cancer rates are so high in Linxian, China, dubbed "the 'world capital' of cancer," is that the soil is deficient in the essential minerals selenium and zinc. In Earl Mindell's Supplement Bible, Earl Mindell RPh PhD, suggests part of the reason American men are five times more likely than Japanese men to die from prostate cancer could be because, in general, "the Asian diet contains four times the amount of selenium as the average American diet."
Another reason it seems to be difficult for Americans to get enough selenium is the processing many of our foods go through before they make it onto grocery store shelves. Mindell points out, for example, that processing wheat into white flour strips it of a great deal of its selenium. One way to get more selenium in your diet might be to eat more organically grown foods, which some studies have shown to contain more selenium as well as higher levels of beta carotene and vitamin E. These two work together with selenium in cancer prevention, according to Alternative Medicine author Burton Goldberg.
Perhaps a more surefire way to boost your selenium intake is to add supplements to your diet. Mindell advocates the use of supplements, saying, "To me, taking selenium supplements, in addition to eating selenium-rich foods, is good insurance against disease." However, for those who oppose taking pills, Dr. Andrew Weil in Ask Dr. Weil says eating just one shelled Brazil nut — grown in the selenium-rich soil of central Brazil — provides 120 micrograms of the mineral, getting you that much closer to the daily target of 200 micrograms.
Although extremely high doses of selenium can have toxic effects, most people are not at risk for such an overdose, and could, in fact, use more of the mineral. Simply adding more selenium-rich foods, such as organically grown vegetables and fruits to your diet, along with supplements, can help reduce your risk of cancer. And another positive side effect of selenium, according to Eat and Heal, by the Editors of FC&A Medical Publishing, is that it can actually improve your mood. Those editors write, "People who don't eat enough selenium-rich foods tend to be grumpier than people with a high dietary intake, according to recent research." So, go ahead and crack a Brazil nut open and smile.