Below you find information on trace minerals that have we have found impack cancer patients.
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- Vanadium
- Zinc
- Selenium
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What is vanadium?
Vanadium is a compound found in tiny amounts in plants and animals. Moreover vanadium is a trace mineral that is present in many foods and may be essential, in small amounts, in the body.
Vanadium supplementation has shown positive effect in peer reviewed studies in:
- Diabetes
- Cancer
- Heart Disease
Diabeties
Diabeties is the 6th leading cause of death in the USA: 72,449 died in 2009 Diabetes: From the procession of the disease leading to life ending complications.
Human studies suggest that vanadium reduce blood sugar levels and improve sensitivity to insulin in people with type 2 diabetes. In one study of people with type 2 diabetes, vanadium also lowered their total and LDL ("bad") cholesterol.
Dr. McNeill (1985) stated that “What we have in the body, I think, is an insulin-enhancing effect,”
Studies showed that vanadium normalized blood glucose levels in humans and animals with type 1 and type 2 diabetes. A recent study found that when people with diabetes were given vanadium, they developed increase sensitivity to insulin, resulting in decreased insulin requirements.
Katherine H. Thompson et. al, (2006) stated that vanadium has been studied over 100 years now, a vanadium-containing compound was assessed clinically for use in treatment of human diabetic patients. In 2000, the first Phase I clinical trial of a designed vanadium-based pharmaceutical agent, the results of the studies have been promising diabetes is a multidimensional disease, created by allopathic drugs such as Prednisone that induced diabetes, deficiencies in mineral, and enzyme, also have been shown to induce diabetes.
Anti-Cancer of Vanadium
Cancer took the lives of 559,888, in 2009 this is why researching the importance’s of minerals such as vanadium, to stop the number 2 killer of the US population.
Rajarshi Sankar Ray et. al., (2006) vanadium has chemopreventive properties and has been considered as an important pharmacological agent. In his study, they evaluated the apoptogenic role of vanadium on human breast cancer cell line. Exposure of breast cancer cells to vanadium led to the induction of apoptosis in a dose-dependent manner. Percentage of apoptosis was maximum (42.5%) at the highest non-toxic dose (250 μM). It was found that vanadium treatment brought about a prominent chromatin condensation, cell cycle arrest leading to apoptosis. These apoptosis based assays demonstrate that vanadium has the as an anti-cancer drug.
Heart Disease
Heart disease is still the number one killer of Americans, with the millions of dollars spent on allopathic drugs each year; the mortality rate was 631,636, in 2009
The ability of vanadium compounds to activate these signaling events may be responsible for their ability to modulate cardiovascular functions. Coderre et, al., (2004), stated that vanadium have been shown to exhibit a large range of insulinomimetic effects in the cardiovascular system, including stimulation of glucose transporter translocation and glucose transport in adult heart muscles (cardiomyocytes). Furthermore, vanadium compounds improves cardiac performance and smooth muscle contractility, and modulates blood pressure in various models of hypertension and insulin resistance.
The Chemistry of Vanadium
Vanadium is believed to stimulate adenylate cyclase by promoting an association of an otherwise inactive nucleotide regulatory guanine nucleotide-binding proteins (G protein) this protein works as a singling switch. Adenylate cyclase catalyzes the formation to cyclic 3’5’-adenosine monophosphate (cAMP) from adenosine triphosphate. Cyclic adenosine monophosphate then stimulates protein kinases, which catalyze the phosphorylation of various enzymes and other cellular proteins in cytoplasm, membranes, mitochondria, ribosomes, and the nucleus. The phosphorylation is nearly always stimularory, and it results secondarily from the hormone-induced stimulation of adenylate cyclase. This is the basis for cAMP’s putative role as a second messenger of hormone action.
Human intake of vanadium is estimates to range from 10 to 60 micrograms (mcg) per day.
The uptake of vanadium by humans mainly takes place through foodstuffs, such as buckwheat, soya beans, olive oil, sunflower oil, apples, eggs shellfish, mushrooms, parsley, dill seed and wine.
Signs of Vanadium Deficiency
Interactions:S
If you are being treated with any of the following medications, you should not use vanadium without first talking to your health care provider.
Anticoagulant or antiplatelet dugs (blood thinners) -- Vanadium may increase the risk of bleeding when taken with these drugs:
- Clopidogrel (Plavix)
- Warfarin (Coumadin)
- Heparin
- Aspirin
Zinc is an essential mineral that is naturally present in some foods. This mineral is involved in numerous aspects of cellular metabolism. Zinc is used as a catalyst in over one hundred (100) enzymatic reactions that take place. However, the enzyme reaction does not bind minerals instead energy is needed to produce the catalytic activity.
Zinc is critical for healthy functioning:
- immune systems
- protein synthesis
- wound healing
- DNA synthesis
- cell division
Zinc also supports normal growth and development during pregnancy, childhood, and adolescence and is required for proper sense of taste and smell. A daily intake of zinc is required to maintain a steady state because the body has no specialized zinc storage system.
Recommended Intakes
Intake recommendations for zinc and other nutrients are provided in the Dietary Reference Intakes (DRIs) developed by the Food and Nutrition Board (FNB) at the Institute of Medicine. DRI is the general term for a set of reference values used for planning and assessing nutrient intakes of healthy people. These values, which vary by age and gender, include the following:
- Recommended Dietary Allowance (RDA): average daily level of intake sufficient to meet the nutrient requirements of nearly all (97%–98%) healthy individuals.
- Adequate Intake (AI): established when evidence is insufficient to develop an RDA and is set at a level assumed to ensure nutritional adequacy.
- Tolerable Upper Intake Level (UL): maximum daily intake unlikely to cause adverse health effects.
Table 1: Recommended Dietary Allowances (RDAs) for Zinc
Age |
Male |
Female |
Pregnancy |
Lactation |
Birth to 6 months |
2 mg* |
2 mg* |
|
|
7 months to 3 years |
3 mg |
3 mg |
|
|
4 to 8 years |
5 mg |
5 mg |
|
|
9 to 13 years |
8 mg |
8 mg |
|
|
14 to 18 years |
11 mg |
9 mg |
13 mg |
14 mg |
19+ years |
11 mg |
8 mg |
11 mg |
12 mg |
* Adequate Intake (AI)
Sources of Zinc
Food:
A wide variety of foods contain zinc. Oysters contain more zinc per serving than any other food, but red meat and poultry provide the majority of zinc in the American diet. Other good food sources include beans, nuts, certain types of seafood (such as crab and lobster), whole grains, fortified breakfast cereals, and dairy products.
The amount of Phylic Acid found in vegetables used as a chelation agent for zinc and other minerals:
Tofu 1.46 - 2.90
Linseed 2.15 2.78
Oat Meal 0.89 2.40
Soy flour 1.24 2.25
Soybeans 1.00 2.22
Corn 0.75 2.22
Peanuts 1.05 1.76
Kidney beans 0.89 1.57
Rye 0.54 1.46
Oat bran 0.60 1.42
Wheat flour 0.25 1.37
Wheat 0.39 1.35
Oat 0.42 1.16
Barley 0.38 1.16
Whole wheat bread 0.43 1.05
Polished rice 0.14 0.60
The bioavailability of zinc from grains and plant foods is lower than that from animal foods, although many grain- and plant-based foods are still good sources of zinc.
Table 2: Selected Food Sources of Zinc
Food |
Milligrams (mg)
per serving |
Percent DV* |
Oysters, 6 medium |
76.7 |
513 |
Beef shanks, cooked, 3 ounces |
8.9 |
59 |
Crab, Alaska king, cooked, 3 ounces |
6.5 |
43 |
Pork shoulder, cooked, 3 ounces |
4.2 |
28 |
Breakfast cereal fortified with 25% of the DV for zinc, ¾ cup serving |
3.8 |
25 |
Chicken leg, roasted, 1 leg |
2.7 |
18 |
Pork tenderloin, cooked, 3 ounces |
2.5 |
17 |
Lobster, cooked, 3 ounces |
2.5 |
17 |
Baked beans, canned, ½ cup |
1.7 |
11 |
Cashews, dry roasted, 1 ounce |
1.6 |
11 |
Yogurt, fruit, low fat, 1 cup |
1.6 |
11 |
Raisin bran, ¾ cup |
1.3 |
9 |
Chickpeas, ½ cup |
1.3 |
9 |
Cheese, Swiss, 1 ounce |
1.1 |
7 |
Almonds, dry roasted, 1 ounce |
1.0 |
7 |
Milk, 1 cup |
0.9 |
6 |
Chicken breast, roasted, ½ breast with skin removed |
0.9 |
6 |
Cheese, cheddar or mozzarella, 1 ounce |
0.9 |
6 |
Kidney beans, cooked, ½ cup |
0.8 |
5 |
Peas, boiled, ½ cup |
0.8 |
5 |
Oatmeal, instant, 1 packet |
0.8 |
5 |
Flounder or sole, cooked, 3 ounces |
0.5 |
3 |
The U.S. Department of Agriculture’s Nutrient Database Web site, http://www.nal.usda.gov/fnic/foodcomp/search/ [11], lists the nutrient content of many foods and provides a comprehensive list of foods containing zinc:
http://www.nal.usda.gov/fnic/foodcomp/Data/SR20/nutrlist/sr20w309.pdf. |
Dietary supplements:
Supplements contain several forms of zinc, including zinc gluconate, zinc sulfate, and zinc acetate. The percentage of elemental zinc varies by form. For example, approximately 23% of zinc sulfate consists of elemental zinc; thus, 220 mg of zinc sulfate contains 50 mg of elemental zinc. The elemental zinc content appears in the Supplement Facts panel on the supplement container. Research has not determined whether differences exist among forms of zinc in absorption, bioavailability, or tolerability.
In addition to standard tablets and capsules, some zinc-containing cold lozenges are labeled as dietary supplements.
Zinc Intakes and Status
Most infants (especially those who are formula fed), children, and adults in the United States consume recommended amounts of zinc according to two national surveys, the 1988-1991 National Health and Nutrition Examination Survey (NHANES III) and the 1994 Continuing Survey of Food Intakes of Individuals (CSFII).
However, some evidence suggests that zinc intakes among older adults might be marginal. An analysis of NHANES III data found that 35%–45% of adults aged 60 years or older had zinc intakes below the estimated average requirement of 6.8 mg/day for elderly females and 9.4 mg/day for elderly males. When the investigators considered intakes from both food and dietary supplements, they found that 20%–25% of older adults still had inadequate zinc intakes.
Zinc intakes might also be low in older adults from the 2%–4% of U.S. households that are food insufficient (sometimes or often not having enough food). Data from NHANES III indicate that adults aged 60 years or older from food-insufficient families had lower intakes of zinc and several other nutrients and were more likely to have zinc intakes below 50% of the RDA on a given day than those from food-sufficient families
Zinc Deficiency
Zinc deficiency is characterized by growth retardation, loss of appetite, and impaired immune function. In more severe cases, zinc deficiency causes hair loss, diarrhea, delayed sexual maturation, impotence, hypogonadism in males, and eye and skin lesions.
Weight loss, delayed healing of wounds, taste abnormalities, and mental lethargy can also occur. Many of these symptoms are non-specific and often associated with other health conditions; therefore, a medical examination is necessary to ascertain whether a zinc deficiency is present.
Zinc nutritional status is difficult to measure adequately even in laboratory tests because of its distribution throughout the body as a component of various proteins and nucleic acids.
Plasma or serum zinc levels are the most commonly used indices for evaluating zinc deficiency, but these levels do not necessarily reflect cellular zinc status due to tight homeostatic control mechanisms. Clinical effects of zinc deficiency can be present in the absence of abnormal laboratory indices. Clinicians consider risk factors (such as inadequate caloric intake, alcoholism, and digestive diseases) and symptoms of zinc deficiency (such as impaired growth in infants and children) when determining the need for zinc supplementation.
Groups at Risk for Zinc Inadequacy
When zinc deficiency does occur, it is usually due to inadequate zinc intake or absorption, increased losses of zinc from the body, or increased requirements for zinc.
People with gastrointestinal and other diseases:
Gastrointestinal surgery and digestive disorders (such as ulcerative colitis, Crohn’s disease, and short bowel syndrome) can decrease zinc absorption and increase endogenous zinc losses primarily from the gastrointestinal tract and, to a lesser extent, from the kidney.
Diseases associated with zinc deficiency include:
Malabsorption syndrome
Chronic liver disease
Chronic renal disease
Sickle cell disease
Diabetes
Malignancy, and other chronic illnesses.
Chronic diarrhea also leads to excessive loss of zinc.
Vegans
Vegans/herbivores typically have lower zinc concentration in their body tissues, leading to decreased height and other neurological issues. Bio-available zinc is lower in vegan diets than from Omnivores diets. However vegetarians to tend to eat fish and sea-food, which means they really are omnivores that prefer non-mammal sources of protein which can contain high zinc concentrations. Vegetarians also typically eat high levels of legumes and whole grains, but these contain phytates that bind zinc and inhibit its absorption into the body.
Vegetarians and vegans sometimes require as much as 50% more of the recommended RDA for zinc than non-omnivores. In addition, they might benefit from using certain food preparation techniques that reduce the binding of zinc by phytates and increase its bioavailability. Techniques to increase zinc bioavailability include soaking beans, grains, and seeds in water for several hours before cooking them and allowing them to sit after soaking until sprouts form. Vegans can also increase their zinc intake by consuming more leavened grain products (such as bread) than unleavened products (such as crackers) because leavening partially breaks down the phytate; thus, the body absorbs more zinc from leavened grains than unleavened grains, but one need to also understand that when one increases the grain they also increase the concentration of sugar in their body.
Carbohydrates and Sugar
When we chew, our body releases amylase into the saliva thus allowing the chemical change from carbohydrate to sugar to begin. This is a concern to people concerned about weight gain, cancer patients, and people with type one and two diabetes. If one has a metabolic deficiency the increase in sugar can lead to acidosis. When one’s body is imbalanced from hyper- or hypo-mineralizing, demineralization can occur, leading to heart disease, diabetes, and other disease and conditions.
Pregnant and lactating women
Pregnant women, particularly those starting their pregnancy with marginal zinc status, are at increased risk of becoming zinc insufficient due, in part, to high fetal requirements for zinc. Lactation can also deplete maternal zinc stores. For these reasons, the RDA for zinc is higher for pregnant and lactating women than for other women (see Table 1) [2].
Older infants who are exclusively breastfed
Breast milk provides sufficient zinc (2 mg/day) for the first 4–6 months of life but does not provide recommended amounts of zinc for infants aged 7–12 months, who need 3 mg/day. In addition to breast milk, infants aged 7–12 months should consume age-appropriate foods containing zinc. Zinc supplementation has improved the growth rate in some children who demonstrate mild-to-moderate growth failure and who have a zinc deficiency.
People with sickle cell disease
Results from a large cross-sectional survey suggest that 44% of children with sickle cell disease have a low plasma zinc concentration, possibly due to increased nutrient requirements and/or poor nutritional status. Zinc deficiency also affects approximately 60%–70% of adults with sickle cell disease. Zinc supplementation has been shown to improve growth in children with sickle cell disease.
Alcoholics
Approximately 30%–50% of alcoholics have low zinc status because ethanol consumption decreases intestinal absorption of zinc and increases urinary zinc excretion.
Zinc the Anti-cancer mineral
Immune function :
Severe zinc deficiency depresses immune function, and even mild to moderate degrees of zinc deficiency can impair macrophage and neutrophil functions, natural killer cell activity, and complement activity. The body requires zinc to develop and activate T-lymphocytes. Individuals with low zinc levels have shown reduced lymphocyte proliferation response to mitogens and other adverse alterations in immunity that can be corrected by zinc supplementation. These alterations in immune function might explain why low zinc status has been associated with increased susceptibility to pneumonia and other infections in children in developing countries and the elderly.
Wound healing:
Zinc helps maintain the integrity of skin and mucosal membranes. Patients with chronic leg ulcers have abnormal zinc metabolism and low serum zinc levels, and clinicians frequently treat skin ulcers with zinc supplements. The authors of A Systematic Review concluded that zinc sulfate might be effective for treating leg ulcers in some patients who have low serum zinc levels. However, research has not shown that the general use of zinc sulfate in patients with chronic leg ulcers or arterial or venous ulcers is effective.
Diarrhea:
Acute diarrhea is associated with high rates of mortality among children in developing countries. Zinc deficiency causes alterations in immune response that probably contribute to increased susceptibility to infections, such as those that cause diarrhea, especially in children.
Studies show that poor, malnourished children in India, Africa, South America, and Southeast Asia experience shorter courses of infectious diarrhea after taking zinc supplements. The children in these studies received 4–40 mg of zinc a day in the form of zinc acetate, zinc gluconate, or zinc sulfate.
In addition, results from a pooled analysis of randomized controlled trials of zinc supplementation in developing countries suggest that zinc helps reduce the duration and severity of diarrhea in zinc-deficient or otherwise malnourished children. Similar findings were reported in a meta-analysis published in 2008 and a 2007 review of zinc supplementation for preventing and treating diarrhea. The effects of zinc supplementation on diarrhea in children with adequate zinc status, such as most children in the United States, are not clear.
The World Health Organization and UNICEF now recommend short-term zinc supplementation (20 mg of zinc per day, or 10 mg for infants under 6 months, for 10–14 days) to treat acute childhood diarrhea.
The common cold :
The effect of zinc treatment on the severity or duration of cold symptoms is controversial. Researchers have hypothesized that zinc directly inhibits rhinovirus binding and replication in the nasal mucosa and suppresses inflammation. However, no data are available to support this hypothesis.
In a randomized, double-blind, placebo-controlled clinical trial, 50 subjects (within 24 hours of developing the common cold) took a zinc acetate lozenge (13.3 mg zinc) or placebo every 2–3 wakeful hours. Compared with placebo, the zinc lozenges significantly reduced the duration of cold symptoms (cough, nasal discharge, and muscle aches).
In another clinical trial involving 273 participants with experimentally induced colds, zinc gluconate lozenges (providing 13.3 mg zinc) significantly reduced the duration of illness compared with placebo but had no effect on symptom severity. However, treatment with zinc acetate lozenges (providing 5 or 11.5 mg zinc) had no effect on either cold duration or severity. Neither zinc gluconate nor zinc acetate lozenges affected the duration or severity of cold symptoms in 281 subjects with natural (not experimentally induced) colds in another trial.
In 77 participants with natural colds, a combination of zinc gluconate nasal spray and zinc orotate lozenges (37 mg zinc every 2–3 wakeful hours) was also found to have no effect on the number of asymptomatic patients after 7 days of treatment.
Caruso et. al., (2007) published a structured review of the effects of zinc lozenges, nasal sprays, and nasal gels on the common cold. Of the 14 randomized, placebo-controlled studies included, 7 (5 using zinc lozenges, 2 using a nasal gel) showed that the zinc treatment had a beneficial effect and 7 (5 using zinc lozenges, 1 using a nasal spray, and 1 using lozenges and a nasal spray) showed no effect. Researches have concluded that zinc can reduce the duration and severity of cold symptoms.
Age-related macular degeneration:
Researchers have suggested that both zinc and antioxidants delay the progression of age-related macular degeneration (AMD) and vision loss, possibly by preventing cellular damage in the retina. In a population-based cohort study in the Netherlands, high dietary intake of zinc as well as beta carotene, vitamin C, and vitamin E was associated with reduced risk of AMD in elderly subjects.
Interactions with iron and copper:
Iron-deficiency anemia is a serious world-wide public health problem. Iron fortification programs have been credited with improving the iron status of millions of women, infants, and children. Fortification of foods with iron does not significantly affect zinc absorption. However, large amounts of supplemental iron (greater than 25 mg) might decrease zinc absorption. Taking iron supplements between meals helps decrease its effect on zinc absorption.
High zinc intakes can inhibit copper absorption, sometimes producing copper deficiency and associated anemia.
A Balanced Approach in Need with Mineral Supplementation
Zinc toxicity can occur in both acute and chronic forms. Acute adverse effects of high zinc intake include nausea, vomiting, loss of appetite, abdominal cramps, diarrhea, and headaches. One case report cited severe nausea and vomiting within 30 minutes of ingesting 4 g of zinc gluconate (570 mg elemental zinc). Intakes of 150–450 mg of zinc per day have been associated with such chronic effects as low copper status, altered iron function, reduced immune function, and reduced levels of high-density lipoproteins. Reductions in a copper-containing enzyme, a marker of copper status, have been reported with even moderately high zinc intakes of approximately 60 mg/day for up to 10 weeks. Doses of 80 mg per day of zinc in the form of zinc oxide for 6.3 years, on average have been associated with a significant increase in hospitalizations for genitourinary causes, raising the possibility that chronically high intakes of zinc adversely affect some aspects of urinary physiology.
The FNB has established ULs for zinc (Table 3). Long-term intakes above the UL increase the risk of adverse health effects. The ULs do not apply to individuals receiving zinc for medical treatment, but such individuals should be under the care of a physician who monitors them for adverse health effects.
Tolerable Upper Intake Levels (ULs) for Zinc [2]
Age |
Male |
Female |
Pregnant |
Lactating |
0 to 6 months |
4 mg |
4 mg |
|
|
7 to 12 months |
5 mg |
5 mg |
|
|
1 to 3 years |
7 mg |
7 mg |
|
|
4 to 8 years |
12 mg |
12 mg |
|
|
9 to 13 years |
23 mg |
23 mg |
|
|
14 to 18 years |
34 mg |
34 mg |
34 mg |
34 mg |
19+ years |
40 mg |
40 mg |
40 mg |
40 mg |
Interactions with Medications:
Zinc supplements have the potential to interact with several types of medications. A few examples are provided below. Individuals taking these medications on a regular basis should discuss their zinc intakes with their healthcare providers.
Antibiotics:
Both quinolone antibiotics (such as Cipro®) and tetracycline antibiotics (such as Achromycin® and Sumycin®) interact with zinc in the gastrointestinal tract, inhibiting the absorption of both zinc and the antibiotic. Taking the antibiotic at least 2 hours before or 4–6 hours after taking a zinc supplement minimizes this interaction.
Penicillamine:
Zinc can reduce the absorption and action of penicillamine, a drug used to treat rheumatoid arthritis. To minimize this interaction, individuals should take zinc supplements at least 2 hours before or after taking penicillamine.
Diuretics:
Thiazide diuretics such as chlorthalidone (Hygroton®) and hydrochlorothiazide (Esidrix® and HydroDIURIL®) increase urinary zinc excretion by as much as 60%. Prolonged use of thiazide diuretics could deplete zinc tissue levels, so clinicians should monitor zinc status in patients taking these medications.
What is selenium?
Selenium is a trace mineral that is essential to good health but required only in small amounts. Selenium is incorporated into proteins to make selenoproteins, which are important antioxidant enzymes. The antioxidant properties of selenoproteins help prevent cellular damage from free radicals. Free radicals are natural by-products of oxygen metabolism that may contribute to the development of chronic diseases such as cancer and heart disease, just to name a few.
Other selenoproteins help regulate thyroid function and play a role in the immune system.
What foods provide selenium?
Plant foods are the major dietary sources of selenium in most countries throughout the world. The content of selenium in food depends on the selenium content of the soil where plants are grown or animals are raised. For example, researchers know that soils in the high plains of northern Nebraska and the Dakotas have very high levels of selenium. People living in those regions generally have the highest selenium intakes in the United States (U.S.). In the U.S., food distribution patterns across the country help prevent people living in low-selenium geographic areas from having low dietary selenium intakes. Soils in some parts of China and Russia have very low amounts of selenium. Selenium deficiency is often reported in those regions because most food in those areas is grown and eaten locally.
Selenium also can be found in some meats and seafood. Animals that eat grains or plants that were grown in selenium-rich soil have higher levels of selenium in their muscles. In the U.S., meats and bread are common sources of dietary selenium. Some nuts are also sources of selenium.
Selenium content of foods can vary. For example, Brazil nuts may contain as much as 544 micrograms of selenium per ounce.
What is the recommended dietary intake for selenium?
Recommended Dietary Allowances (RDA) for selenium for children and adults
Age(years) Males and Females(μg/day) Pregnancy(μg/day) Lactation(μg/day)
1-3 y 20 N/A N/A
4-8 y 30 N/A N/A
9-13 y 40 N/A N/A
14-18 y 55 60 70
19 y + 55 60 70
There is insufficient information on selenium to establish a RDA for infants. An Adequate Intake (AI) has been established that is based on the amount of selenium consumed by healthy infants who are fed breast milk. Table 3 lists the AIs for selenium, in micrograms (μg or mcg) per day, for infants.
Table 2: Adequate Intake for selenium for infants
Age
(months) Males and Females (μg/day)
0-6 months 15
7-12 months 20
Results of the National Health and Nutrition Examination Survey (NHANES III-1988-94) indicated that diets of most Americans provide recommended amounts of selenium. The INTERMAP study examined nutrient intakes of almost 5,000 middle-aged men and women in four countries in the late 1990s, including the U.S. The primary aim of the study was to evaluate the effect of dietary micronutrients on blood pressure. Each study participant completed four, 24-hour dietary recalls, during which they were asked to record everything consumed (food, beverages, and dietary supplements) over the previous 24 hours. Selenium intake was lowest among residents of China, the country with the highest known rate of selenium deficiency. Mean dietary intake of selenium of U.S. participants was 153 μg for men and 109 μg for women. Both values exceed the recommended selenium intake for adults and are further evidence of adequate selenium intakes in the U.S.
When can selenium deficiency occur?
Human selenium deficiency is believed to be rare in the U.S. but is seen in other countries, most notably China, where soil concentration of selenium is low. There is evidence that selenium deficiency may contribute to development of a form of heart disease, hypothyroidism, and a weakened immune system. There is also evidence that selenium deficiency does not usually cause illness by itself. Rather, it can make the body more susceptible to illnesses caused by other nutritional, biochemical or infectious stresses.
- Three specific diseases have been associated with selenium deficiency: Keshan Disease, which results in an enlarged heart and poor heart function, occurs in selenium deficient children.
- Kashin-Beck Disease, which results in osteoarthropathy
- Myxedematous Endemic Cretinism, which results in mental retardation
Keshan disease was first described in the early 1930s in China, and is still seen in large areas of the Chinese countryside with selenium poor soil. Dietary intake in these areas is less than 19 micrograms per day for men and less than 13 micrograms per day for women, significantly lower than the current RDA for selenium. Researchers believe that selenium deficient people infected with a specific virus are most likely to develop Keshan disease.
Selenium deficiency has also been seen in people who rely on Total Parenteral Nutrition (TPN) as their sole source of nutrition. TPN is a method of feeding nutrients through an intravenous (IV) line to people whose digestive systems do not function. Forms of nutrients that do not require digestion are dissolved in liquid and infused through the IV line. It is important for TPN solutions to provide selenium in order to prevent a deficiency. Physicians can monitor the selenium status of individuals receiving TPN to make sure they are receiving adequate amounts.
Severe gastrointestinal disorders may decrease the absorption of selenium, resulting in selenium depletion or deficiency. Gastrointestinal problems that impair selenium absorption usually affect absorption of other nutrients as well
Who may need supplemental selenium?
Selenium deficiency is associated with severe gastrointestinal problems, such as Crohn's disease, or with surgical removal of part of the stomach. These and other gastrointestinal disorders can impair selenium absorption. People with acute severe illness who develop inflammation and widespread infection often have decreased levels of selenium in their blood.
Selenium & Iodine Deficiency
People with iodine deficiency may also benefit from selenium supplementation. Researchers believe that selenium deficiency may worsen the effects of iodine deficiency on thyroid function, and that adequate selenium nutritional status may help protect against some of the neurological effects of iodine deficiency. Researchers involved in the Supplementation of vitamins and minerals studied in France, which was designed to assess the effect of vitamin and mineral supplements on chronic disease risk, evaluated the relationship between goiter and selenium in a subset of this research population. Their findings suggest that selenium supplements may be protective against goiter, which refers to enlargement of the thyroid gland.
As noted above, selenium supplementation during TPN administration is now routine. While specific medical problems such as those described above indicate a need for selenium supplementation, evidence is lacking for recommending selenium supplements for healthy children and adults.
Selenium supplements
Selenium occurs in staple foods such as corn, wheat, and soybean as selenomethionine, the organic selenium analogue of the amino acid methionine. Selenomethionine can be incorporated into body proteins in place of methionine, and serves as a vehicle for selenium storage in organs and tissues. Selenium supplements may also contain sodium selenite and sodium selenate, two inorganic forms of selenium. Selenomethionine is generally considered to be the best absorbed and utilized form of selenium.
Selenium is also available in 'high selenium yeasts', which may contain as much as 1,000 to 2,000 micrograms of selenium per gram. Most of the selenium in these yeasts is in the form of selenomethionine. This form of selenium was used in the large scale cancer prevention trial in 1983, which demonstrated that taking a daily supplement containing 200 micrograms of selenium per day could lower the risk of developing prostate, lung, and colorectal cancer. However, some yeast may contain inorganic forms of selenium, which are not utilized as well as selenomethionine.
A study conducted in 1995 suggested that the organic forms of selenium increased blood selenium concentration to a greater extent than inorganic forms. However, it did not significantly improve the activity of the selenium-dependent enzyme, glutathione peroxidase [33]. Researchers are continuing to examine the effects of different chemical forms of selenium, but the organic form currently appears to be the best choice.
What are some current issues and controversies about selenium?
Selenium and cancer
Observational studies indicate that death from cancer, including lung, colorectal, and prostate cancers, is lower among people with higher blood levels or intake of selenium [34-40]. In addition, the incidence of nonmelanoma skin cancer is significantly higher in areas of the United States with low soil selenium content [37]. The effect of selenium supplementation on the recurrence of different types of skin cancers was studied in seven dermatology clinics in the U.S. from 1983 through the early 1990s. Taking a daily supplement containing 200 μg of selenium did not affect recurrence of skin cancer, but significantly reduced the occurrence and death from total cancers. The incidence of prostate cancer, colorectal cancer, and lung cancer was notably lower in the group given selenium supplements.
Research suggests that selenium affects cancer risk in two ways. As an anti-oxidant, selenium can help protect the body from damaging effects of free radicals. Selenium may also prevent or slow tumor growth. Certain breakdown products of selenium are believed to prevent tumor growth by enhancing immune cell activity and suppressing development of blood vessels to the tumor.
However, not all studies have shown a relationship between selenium status and cancer. In 1982, over 60,000 participants of the Nurse's Health Study with no history of cancer submitted toenail clippings for selenium analysis. Toenails are thought to reflect selenium status over the previous year. After three and a half years of data collection, researchers compared toenail selenium levels of nurses with and without cancer. Those nurses with higher levels of selenium in their toenails did not have a reduced risk of cancer.
Two long-term studies, the SU.VI.MAX study in France and the Selenium and Vitamin E Cancer Prevention Trial (SELECT) in the United States and Canada, investigated whether selenium combined with at least one other dietary supplement could reduce the risk of prostate cancer in men.
The SU.VI.MAX study examined the effects of a supplement package containing moderate doses of vitamins E and C, beta-carotene, zinc, and selenium (100 μg/day) versus placebo on the risk of chronic diseases such as cancer and cardiovascular disease. Among the 5,141 men enrolled, those randomized to the supplements who began the study with a normal (<3 ng/ml) PSA (prostate specific antigen) level at baseline had their risk of prostate cancer reduced by half. Among the men whose PSA levels were elevated at baseline, however, use of the supplements was associated with an increased incidence of prostate cancer of borderline statistical significance compared to placebo.
The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was a very large randomized clinical trial begun in 2001 specifically designed to determine whether 7-12 years of daily supplementation with selenium (200 μg), with or without synthetic vitamin E (400 IU), reduces the number of new prostate cancers in healthy men (PSA ≤4 ng/ml at baseline) [46-47]. The trial, which had enrolled >35,000 men, was discontinued in October 2008 when an analysis found that the supplements, taken alone or together for an average of 5.5 years, did not prevent prostate cancer. Study staff members will continue to monitor participants' health for an additional 3 years.
Selenium and heart disease
Some population surveys have suggested an association between lower antioxidant intake and a greater incidence of heart disease [47]. Evidence also suggests that oxidative stress from free radicals, which are natural by-products of oxygen metabolism, may promote heart disease [48-50]. For example, it is the oxidized form of low-density lipoproteins (LDL, often called "bad" cholesterol) that promotes plaque build-up in coronary arteries [49]. Selenium is one of a group of antioxidants that may help limit the oxidation of LDL cholesterol and thereby help to prevent coronary artery disease [48-50]. Currently there is insufficient evidence available to recommend selenium supplements for the prevention of coronary heart disease.
Selenium and arthritis
Surveys indicate that individuals with rheumatoid arthritis, a chronic disease that causes pain, stiffness, swelling, and loss of function in joints, have reduced selenium levels in their blood. In addition, some individuals with arthritis have a low selenium intake.
The body's immune system naturally makes free radicals that can help destroy invading organisms and damaged tissue, but that can also harm healthy tissue. Selenium, as an antioxidant, may help to relieve symptoms of arthritis by controlling levels of free radicals. Current findings are considered preliminary, and further research is needed before selenium supplements can be recommended for individuals with arthritis.
Selenium and HIV
HIV/AIDS malabsorption can deplete levels of many nutrients, including selenium. Selenium deficiency is associated with decreased immune cell counts, increased disease progression, and high risk of death in the HIV/AIDS population. HIV/AIDS gradually destroys the immune system, and oxidative stress may contribute to further damage of immune cells. Antioxidant nutrients such as selenium help protect cells from oxidative stress, thus potentially slowing progression of the disease. Selenium also may be needed for the replication of the HIV virus, which could further deplete levels of selenium.
An examination of 125 HIV-positive men and women linked selenium deficiency with a higher rate of death from HIV. In a small study of 24 children with HIV who were observed for five years, those with low selenium levels died at a younger age, which may indicate faster disease progression. Results of research studies have led experts to suggest that selenium status may be a significant predictor of survival for those infected with HIV.
Researchers continue to investigate the relationship between selenium and HIV/AIDS, including the effect of selenium levels on disease progression and mortality. There is insufficient evidence to routinely recommend selenium supplements for individuals with HIV/AIDS, but physicians may prescribe such supplements as part of an overall treatment plan. It is also important for HIV-positive individuals to consume recommended amounts of selenium in their diet.
What is the health risk of too much selenium?
High blood levels of selenium (greater than 100 μg/dL) can result in a condition called selenosis. Symptoms of selenosis include gastrointestinal upsets, hair loss, white blotchy nails, garlic breath odor, fatigue, irritability, and mild nerve damage.
Selenium toxicity is rare in the U.S. The few reported cases have been associated with industrial accidents and a manufacturing error that led to an excessively high dose of selenium in a supplement. The Institute of Medicine of the National Academy of Sciences has set a tolerable upper intake level (UL) for selenium at 400 micrograms per day for adults to prevent the risk of developing selenosis. Table 4 lists ULs for selenium, in micrograms per day, for infants, children, and adults.
Table 4: Tolerable Upper Intake Levels for selenium for infants, children, and adults
Age Males and Females(mcg/day)
0 - 6 months 45
7 - 12 months 60
1-3 y 90
4-8 y 150
9-13 y 280
14-18 y 400
19 y + 400
Selecting a healthful diet
The 2000 Dietary Guidelines for Americans states, "Different foods contain different nutrients and other healthful substances. No single food can supply all the nutrients in the amounts you need".
Zinc and Healthful Diets
According to the 2005 Dietary Guidelines for Americans, "Nutrient needs should be met primarily through consuming foods. Foods provide an array of nutrients and other compounds that may have beneficial effects on health. In certain cases, fortified foods and dietary supplements may be useful sources of one or more nutrients that otherwise might be consumed in less than recommended amounts. However, dietary supplements, while recommended to people who show deficiency one should not assume that taking a multi mineral will improve their health. One needs to determine if they are in-fact deficient, before one starts on a hyper-mineralization diet.”
Eat the very best foods- organic, natural, 80% raw.
Check to see if the foods you eat daily have the proper ratio of minerals and vitamins for a healthy life. One should daily self-diagnose using the “Classic signs of deficiency.” Example: White spots on one’s nails is one of the classic signs of zinc deficiency… noting these signs is a proactive approach to ones health.
Consider having hair analysis done to determine if you in-fact suffer from mineral toxicities, e.g., too much of one mineral or a heavy metal such as lead.
Consider mineral deficiencies; do you in fact have all the minerals and metal in your body to keep you healthy?
Keep in mind that your are an individual not a statistical norm on a chart.
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