Advantages of taking minerals and natural health supplements in diet

Selenium is a vital trace mineral found in body proteins known as selenoproteins. When synthesized, these substances create glutathione peroxidase, an essential antioxidant enzyme. Through its antioxidant properties, selenium significantly boosts immune system function, enabling this mineral to efficiently fight disease and infections while also detoxifying the body from chronic exposure to such things as radiation, chemotherapy medications, environmental pollutants and other toxic drugs.

Overall, researchers believe that selenium is one of the most crucial elements in disease prevention. The highest concentrations of selenium are found in the liver, kidney, pancreas, spleen and the testes of males.

Selenium’s antioxidant properties may be this mineral’s most significant contribution to health. Research now shows that a growing number of diseases are a direct result of free radical damage.

When used in conjunction with vitamin E , another important antioxidant, selenium becomes a powerhouse protector against free radicals responsible for many degenerative diseases and aging. The natural process of DNA oxidation in energy production causes the byproduct cells of this process to attack other healthy cells, resulting in the destruction of the cell membranes and interference in their genetic material. This metabolic process frequently results in such conditions as heart disease, arthritis and cancer however, selenium is known to neutralize and prevent much of the damage caused by free radicals.

With cancer cases steadily rising, prevention and cure are at the forefront of much of today’s research. Selenium is proving to be highly effective in this area, especially in cases of lung, esophageal, prostate and colon cancers.

Selenium is key to the metabolism of iodine in the thyroid gland and as well, synthesizing hormones produced by this gland into a useable and active substance required by every cell within the body.

In one of the largest and most significant cancer studies to date, results from both the University of Arizona and Cornell University were reviewed. This 10-year study was originally designed to study the effectiveness of selenium in cases of skin cancer; the participants mostly were residing on the East Coast in such areas as Connecticut, North Carolina, South Carolina, Georgia and Florida. This group was chosen because people living in these areas are normally at a higher risk for skin cancer and as well, this region is known to be low in dietary selenium resulting from depleted soil sources.

At some point the study expanded however, and the investigation looked at the general efficacy of selenium supplements on cancer prevention as a whole. The results were astounding according to researchers. Participants that took 200 mcg of selenium daily over the period of the study, when compared to the rest of the population, had 71 percent fewer incidences of prostate cancer, 67 percent fewer cases of esophageal cancer, 62 percent less colorectal tumors and 46 percent fewer cases of lung cancer. As well, those involved in the study had a much lower fatality rate from cancer than the rest of the population¹.

Additionally, earlier cancer trials showed that those individuals already diagnosed with cancer, who also had the lowest plasma levels of selenium, were the most likely to develop additional tumors compared to those people with higher blood levels of the mineral. It was further found that lower levels of selenium are directly related to higher cancer recurrence rates and an increased risk of the cancer spreading, both resulting in a decreased survival rate.

In areas where selenium soil levels are lower, cancer incidence is higher, especially in the cases of skin and colon cancer. It appears that foods normally high in selenium, when grown in depleted soil, lose much of their nutrient content. These findings are even more important considering other research concludes that eating a diet high in selenium rich foods and other antioxidants may reduce the risk of prostate cancer. Further studies show that selenium used in conjunction with other powerful antioxidants such as vitamin C, beta-carotene, vitamin E and coenzyme Q10, along with essential fatty acids, may decrease the incidence of breast cancer spreading as well as the overall mortality rate of those women suffering from this disease.

According to several researchers, selenium works in two specific ways to prevent cancer. The antioxidant properties of this mineral are very effective in protecting the cells from free radical damage, as well it is suggested that particular substances resulting from selenium metabolism also enhance immunity and inhibit the development of blood vessels to the tumors, thereby cutting off their life supply.

Like in many cases of nutritional supplements however, not all studies agree with the effectiveness of selenium in cancer prevention and treatment. One recognized study conducted in 1982 investigated toenail clippings as an indicator of selenium levels in 60,000 nurses. Researchers believed that toenails retain selenium and as such, an accurate record of selenium levels could be obtained from the previous year. After much tedious work, the study concluded that those participants with higher levels of selenium, as reported in their toenail clippings, did not have a reduced risk of cancer compared to individuals who had lower selenium levels².

Currently, a study sponsored by the National Institutes of Health (NIIH) is underway and researchers hope to obtain evidence one way or another on the effectiveness of selenium, This trail, named SELECT, is investigating the effectiveness of selenium and vitamin E in cancer prevention. The subjects, 32,400 healthy adult males, are being given 200 mcg of selenium daily along with 400 IU of vitamin E. Results of the study are expected some time after the trial is scheduled to end in 2013³ I n the interim, the evidence supporting the anticancer properties of selenium is quite overwhelming and health professionals still suggest eating a balanced diet rich in antioxidants.

Large population studies also report that antioxidant intake is directly proportional to incidence of heart disease. Researchers attribute these findings to the destruction caused by free radicals that naturally attack healthy cells. Low density lipoproteins, also known as LDL or bad cholesterol, result from oxidation. LDL is widely recognized as a key factor in atherosclerosis, or plaque buildup in the coronary arteries. It is surmised that selenium’s antioxidant properties not only neutralize free radical activity, decreasing LDL but also increase the level of HDL (good) cholesterol. It is also believed that selenium may work to decrease the risk of blood clots by promoting ‘cleaner’, less sticky blood and as such, lowering the risk of heart attack and stroke.⁴ A long-term study in France looked at the effects of antioxidant vitamins and minerals on chronic diseases such as heart disease and cancer. SU.VI.MAX began in 1994 and followed 12,000 adults over an eight-year period. Results of this study are highly anticipated.⁵ Suppressed immunity is a major factor in disease and contributes to several serious conditions. Selenium is considered a key nutrient in white blood cell production and regulation. These cells are the body’s primary defense against illness and infection. One particular study looked at 725 elderly adults who were given the influenza vaccine and either a supplement of zinc and selenium or a placebo. It was found that those receiving the supplement had a higher immune response to the vaccine than those who received the placebo.⁶ It was further found that deficiencies in selenium could actually encourage the flu vaccine to mutate into more dangerous and resistant infections including lung inflammation.⁷

HIV and AIDS are deadly immune diseases. Research indicates that as the disease progresses selenium levels steadily decline in these individuals, resulting in a variety of symptoms and an increased risk of fatality. Free radical damage contributes to further damage of these already compromised immune cells and significantly increases the rate of progression of the disease, since selenium is known to prevent the damage due to free radical it can help to potentially slow down the rate of progression.

A further study observed 24 children suffering from HIV over a five-year period. It was concluded that those children with lower selenium levels had earlier mortality rates, leading researchers to believe that selenium was a key factor in the progression of the disease. It is surmised that selenium levels could therefore, be a good predictor of survival rates in cases of HIV.⁸ Some studies have also looked to selenium, among other nutrients, as a treatment in weight loss commonly associated with HIV and AIDS patients. Although the findings are positive, and those receiving the supplements gained significant weight in comparison to placebo groups, researchers cannot say whether selenium alone is responsible.⁹ Further research is necessary.

Inflammatory diseases rank high among complaints received by health professionals. Rheumatoid arthritis is no longer considered an elderly condition. As environmental pollutants continue to rise and the nutritional value of the typical North America diet tends to decline, cases of arthritis are seen in much younger patients.

Research indicates that people suffering from this painful condition that causes swelling, stiffness and loss of mobility in the joints, have low plasma levels of selenium. Antioxidants like selenium fight the free radicals that in some cases lead to arthritis and as such, those people who are low in this nutrient are naturally at a higher risk of developing this degenerative condition. Selenium supplements, if taken regularly, may help to prevent the onset of rheumatoid arthritis. In cases in which the disease has progressed, selenium has been shown to alleviate some of the painful symptoms of this disease.¹⁰

In much the same way as selenium works in cases of arthritis, this nutrient, when combined with vitamin E, is known to be effective in cases of lupus and other inflammatory autoimmune diseases. The antioxidant properties of both of these nutrients may help to protect the heart, joints, skin, blood vessels and other inflammatory prone parts of the body.

Those with inflammatory bowel disease (IBD) including Chon’s disease and ulcerative colitis, have lower levels of selenium as well as many other essential nutrients and vitamins. Much of this can be explained by the lack of nutritional content many of these people receive as a result of malabsorption and as well symptoms including diarrhea and vomiting, all of which contribute to these deficiencies. In such cases, selenium supplements may be necessary to not only restore nutrient levels back within normal range, but they could also reduce the symptoms associated with these gastrointestinal conditions. People with psoriasis and eczema have also reported positive outcomes when using this antioxidant combination.

Studies further indicate that people with an iodine deficiency could greatly benefit from selenium supplementation. Research shows that low levels of selenium can exasperate the symptoms of iodine deficiency on the thyroid gland. Studies in France indicate that selenium may protect the thyroid gland from enlarging or developing a goiter, a common side effect of iodine deficiency.¹¹

Research into the efficacy of selenium in such cases as male infertility, miscarriage, liver disease, pancreatic disorders, diabetes, depression, herpes cold sores, shingles, burns, as well as macular degeneration and cataracts have all proven positive in prevention and/or reducing symptoms. While the list of selenium’s health benefits continues to grow, researchers also continue to investigate a number of possible therapeutic uses for this mineral.

For the most part, plant foods are the major source of selenium. The concentrations and quality of selenium found in these sources however, varies considerably depending on where they are grown. For instance, soils in some areas of Russia and China have very low selenium levels, while parts of the US such as northern Nebraska and both South and North Dakota, have extremely high soil levels of this mineral. Some seafood and meat also contains selenium, but again, the concentration of selenium in animals will depend on where they were grazed.

Probably the highest food source of selenium is Brazil nuts, but the consistency of selenium levels varies as well. For instance, one ounce of Brazil nuts may contain as much as 544 mcg of selenium, which in comparison to the FDA’s listed recommended daily allowance of only 55 mcg is extremely high. In some instances, one Brazil nut alone may contain 120 mcg of selenium. Although the actual amount of selenium in these nuts can be much lower, nutritionists still recommend only eating Brazil nuts in moderation because the potential for selenium overload is potentially quite high.

Other food sources include; fish such as tuna, cod, mackerel, halibut, flounder, smelts and herring; meat including liver, beef, turkey and chicken; shellfish like lobster, scallops and oysters; whole grains such as wheat germ and oats as well as rice and pasta; diary products including cottage cheese, cheese and butter and garlic, corn, soybeans as well as sunflower seeds. Nutritionists advocate eating as many whole and unprocessed foods as possible since selenium is destroyed when foods are processed or refined. Canned, frozen and especially commercially prepared foods are very poor sources of selenium. Herbs that contain selenium include alfalfa, burdock root, catnip, cayenne, chamomile, chickweed, fennel seed, fenugreek, garlic, ginseng, hawthorn berry, hosp, horsetail, lemongrass, milk thistle , nettle , oat straw, parsley, peppermint, raspberry leaf, rose hips, sarsaparilla, uva ursi, yarrow and yellow dock.

The organic form of selenium is called selenomethionine, which is the form found in foods, Supplements may also contain sodium selenite and sodium selenate, both of which are inorganic forms of this mineral. For the most part, selenomethionine is considered to be the easiest form to both absorb and metabolize. Another form of selenium is ‘high selenium yeast’, some of which contains as much as 1,000 to 2,000 mcg of selenium per gram. This is the form used in many of the cancer trials.

The usual recommended dose of selenium is 55 mcg daily for women and 70 mcg per day for men. Therapeutic doses range from about 200 mcg per day for treatment of macular degeneration to 600 mcg per day in cases of shingles and cold sores. Health professionals also suggest taking selenium along with vitamin E to enhance its healing properties. For the best antioxidant effects, experts recommend also including vitamin C, beta-carotene, grape seed extract, coQ10, N-acetylcysteine (NAC), alpha-lipoic acid as well as green tea extracts.

Though the selenium deficiency is not directly associated with disease, it does make the immune system more susceptible to diseases such as heart disease, hypothyroidism and numerous immune disorders. Keshan Disease, common in parts of China, results in an enlarged heart and is frequently diagnosed in children who are deficient in selenium. A specific form of mental retardation as well as osteoarthropathy can also result from deficient levels of selenium.

There are a few drug interactions with selenium including some cholesterol lowering medications. In such cases, the effectiveness of the drugs may be lowered so it is always best to consult a health professional prior to taking any herbs or supplements, especially if you are already taking prescription medications.

Too much selenium however, is also a concern, specifically, a condition known as selenosis that causes hair loss, garlic breath smell, fatigue, stomach upset, irritability and often mild nerve damage can result from doses exceeding 1000 mcg per day. Selenium toxicity however, is rare in the US and of those few cases reported, all have been associated with industrial accidents and in one case a manufacturer’s error resulting in people consuming 500 times the RDA from bottles actually containing tablets of 200 mcg each, but marked as 30 mcg. Overall, health professionals state that there is a risk of selenium buildup in doses of 900 mcg or more at one time or 600 mcg per day over an extended period of time. If you are taking selenium supplements it is also important to account for food intake of this mineral as well so as not to overload your system.

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