Tuesday 29 May 2012

A GOOD LONG KNOWLEDGE INTO YOUR VITAMINS AND SUPPLEMENTS


There are many factors that cause nutrient depletion, such as poor diet, stress, exercise, use of prescription drugs, environmental toxicity, and excessive alcohol intake. For many micronutrients, deficiency, inadequate intake or nutrient depletion is common relative to the RDA. This is why supplements are so important in making up for short comings in the diet and preventing deficiencies.


VITAMINS
There are 13 essential vitamins that our bodies need for proper growth, function, and maintenance of healthy tissues. The vitamins are either water-soluble or fat-soluble. The B-vitamins and vitamin C dissolve in water and are easily eliminated from the body. Adverse reactions, even with high dose supplements, are rare with these vitamins. Fat soluble vitamins (A, D, and E) are not readily excreted from the body and have the potential to accumulate in the tissues and cause adverse effects at high doses.

Vitamin A
• Found in animal foods and converted from beta-carotene in plant foods.
• Required for vision, gene expression, reproduction, embryonic development, red
blood cell production, and immune function.
• Prescription vitamin A derivatives are used to treat skin conditions (acne) and retinitis pigmentosa (genetic eye disease).
• Deficiency is rare in Canada, but common in developing countries due to malnutrition. It causes night blindness, dry eyes and skin, and impaired growth.
• Drugs that deplete vitamin A: cholestyramine, colestipol, mineral oil, and neomycin.
• Supplements should be avoided by those at risk of lung cancer (smokers) or liver toxicity (alcoholics, liver disease).
• Doses greater than 10,000 IU daily should be avoided by pregnant women due to the risk of birth defects. Most prenatal vitamins provide 5,000 IU.
• Doses greater than 5,000 IU may increase risk of osteoporosis.
• Supplements of vitamin A beyond what is provided in a multivitamin are not recommended due to risk of toxicity. To avoid this risk, choose a multivitamin that contains beta-carotene, which is converted to vitamin A in the liver, but is not as- sociated with health risks.

Vitamin B1 (Thiamine)
• Required for energy production, nerve and muscle function, enzyme reactions, and fatty acid production.
• Deficiency causes beriberi, a disease that affects cardiovascular, nervous, muscular, and gastrointestinal systems.
• Deficiency is common in developing countries; in North America it occurs in alcoholics, those with kidney disease, malabsorption syndromes (celiac disease), and in those with poor diets.
• Drugs that deplete vitamin B1: furosemide, antibiotics, oral contraceptives, and phenytoin.
• Most people get adequate thiamine from diet and/or a multivitamin.
Vitamin B2 (Riboflavin)
• Required for energy metabolism, enzyme reactions, vision, and skin/hair/nail health; functions as an antioxidant; activates vitamin B6, niacin, and folate.
• May play a role in preventing migraine headaches and cataracts.
• Deficiency occurs in alcoholics, the elderly, and those with poor diets.
• Symptoms of deficiency include sore throat; redness/swelling of the mouth, throat, tongue, lips, and skin; decreased red blood cell count; and blood vessel growth over the eyes. Deficiency may impair iron absorption and increase risk of pre-eclampsia in pregnant women.
• Drugs that deplete vitamin B2: antibiotics, chlorpromazine, amitriptyline, adriamy- cin, and phenobarbitol.
• Most people get adequate riboflavin from diet and/or a multivitamin.

Vitamin B3 (Niacin)
• Required for energy metabolism, enzyme reactions, skin and nerve health, and digestion.
• High doses of nicotinic acid (3 g daily) can lower cholesterol (reduce LDL and tri- glycerides and increase HDL) and reduce the risk of heart attack and stroke; high dosages should be supervised by a physician.
• Deficiency causes pellagra, the symptoms of which are skin rash, diarrhea, demen- tia, and death.
• Deficiency may be caused by poor diet, malabsorption diseases, dialysis, and HIV.
• Drugs that deplete vitamin B3: antibiotics, isoniazid, and 5-Fluorouracil (chemotherapy).
• High-dose niacin, taken along with statin drugs (i.e., lovastatin), may increase the risk of rhabdomyolysis (muscle degeneration and kidney disease).
• Most people get adequate niacin from diet and/or a multivitamin; supplements may be recommended for those with high cholesterol.

Vitamin B5 (Pantothenic Acid)
• Required for carbohydrate metabolism, adrenal function, enzyme reactions, and production of fats, cholesterol, bile acids, hormones, neurotransmitters, and red blood cells.
• Deficiency is rare, except in malnutrition, and causes burning/tingling in hands and feet, fatigue, and headache.
• Drugs that deplete vitamin B5: oral contraceptives, amitriptyline, imipramine, and desipramine.
• Most people get adequate niacin from diet and/or a multivitamin.

Vitamin B6 (Pyridoxine)
• Necessary for protein and fat metabolism, hormone function (estrogen and tes- tosterone), and the production of red blood cells, niacin, and neurotransmitters (serotonin, dopamine, and norepinephrine).
• Used therapeutically for PMS, depression, morning sickness, carpal tunnel syn- drome, and heart health (lowers homocysteine, an amino acid that, at high levels, can cause arteriosclerosis and build up arterial plaque).
• Deficiency is uncommon, except in alcoholics and the elderly, and causes seizures, irritability, depression, confusion, mouth sores, and impaired immune function.
• Drugs that deplete vitamin B6: antibiotics, oral contraceptives, isoniazid, penicil- lamine, and Parkinson’s drugs.
• Supplements are recommended for the elderly, alcoholics, and those with poor diets.

Vitamin B12 (Cobalamin)
• Required for nerve function, synthesis of DNA and RNA, metabolism of energy, enzyme reactions, and production of red blood cells.
• Used therapeutically for heart health (lowers homocysteine), male infertility, prevention of neural tube defects, asthma, and cancer prevention.
• Deficiency is common among the elderly and those with poor diets, pernicious anemia, depression, Alzheimer’s, or malabsorption conditions (celiac disease).
• Deficiency symptoms: anemia, appetite loss, constipation, numbness and tingling in the extremities, and confusion. Pregnant women with deficiency have increased risk of giving birth to a child with neural tube defects.
• Drugs that deplete B12: acid-lowering drugs (omeprazole, lansoprazole, ranitidine), oral contraceptives, antibiotics, cholestyramine, and metformin.
• Supplements are recommended for those over age 50, vegetarians, women planning to become pregnant, those with poor diets, and those at risk of heart disease.

Biotin
• Part of the B-vitamin family; involved in the synthesis of fat, glycogen, and amino acids and enzyme reactions; required for DNA replication; important for healthy hair and nails.
• Used therapeutically to strengthen fingernails.
• Deficiency is rare except in those with hereditary disorders of biotin metabolism, liver disease, and during pregnancy (due to increased needs). It can also occur in those who consume raw egg white for prolonged periods (weeks to years) because a protein found in egg white (avidin) binds biotin and prevents its absorption or in those given intravenous feeding without biotin supplementation.
• Deficiency symptoms include hair loss; scaly red rash around the eyes, nose, mouth, and genital area; depression; lethargy; hallucination; numbness and tingling of the extremities; and impaired glucose utilization and immune system function.
• Drugs that deplete biotin: primidone, carbamazepine, phenobarbital, phentyoin, valproic acid, and antibiotics.
• Most people get adequate biotin from diet and/or supplements.
Folate (Folic Acid)
• Part of the B-vitamin family; known as folate when it occurs in foods, or as folic acid when present in supplements or added to foods.
• Required for cell division, growth, amino acid metabolism, enzyme reactions, and production of RNA, DNA, and red blood cells.
• Used for heart health (lowers homocysteine) and prevention of cancer (colon and cervical) and birth defects (neural tube).
• Deficiency occurs in alcoholics and those with poor diets, and causes anemia, fatigue, weakness, headache, hair loss, diarrhea, and poor immune function. Pregnancy or cancer results in increased rates of cell division and metabolism, in- creasing the need for folate.
• Drugs that deplete folate: non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and aspirin, phenytoin, methotrexate phenobarbital, cholestyramine, colestipol, trimethoprim, and sulfasalazine.
• Supplements are recommended for most adults for heart and cancer protection, and especially for pregnant women; multivitamins typically provide the recommended amount of 400 mcg per day.

Vitamin C (Ascorbic Acid)
• Required for synthesis of collagen (structural component of blood vessels, tendons, and bone), norepinephrine (neurotransmitter), and carnitine (amino acid involved in energy production); promotes wound healing; supports immune function and gum health; and has antioxidant properties.
• Used to prevent cataracts, macular degeneration, heart disease, stroke, cancer, and colds; improve wound healing and response to stress; reduce bronchial spasms in asthmatics; and prevent lead toxicity.
• Severe deficiency causes scurvy (bleeding, bruising, hair and tooth loss, joint pain, and swelling), which is rare today.
• Marginal deficiencies are common among the elderly, alcoholics, and those with cancer, chronic illness, or stress. Symptoms include fatigue, easy bruising, poor wound healing and appetite, anemia, and sore joints.
• Drugs that deplete vitamin C: oral contraceptives, aspirin, corticosteroids, and furosemide.
• Large doses of vitamin C (greater than 1,000 mg/day) may reduce the effect of warfarin (blood thinning drug).
• The Linus Pauling Institute recommends 400 mg of vitamin C daily, which is higher than the RDA, yet much lower than the UL. Most multivitamin supplements provide 60 mg of vitamin C.
• Natural and synthetic forms are chemically identical and have the same effects on the body.
• Mineral salts of ascorbic acid (i.e., calcium ascorbate) are buffered and therefore less acidic and less likely to cause upset stomach.
Vitamin D
• Regulates calcium and phosphorus levels and promotes absorption of these miner- als for growth of bones and teeth; involved in insulin secretion; supports immune function; regulates blood pressure.
• Vitamin D can be produced in the skin upon exposure to sunlight or must be obtained from the diet.
• Used to prevent and treat osteoporosis, psoriasis, autoimmune disease, and to re- duce the risk of cancer.
• Deficiency occurs with inadequate dietary intake, limited sun exposure, kidney or liver disease, and alcoholism. Elderly, dark skinned, obese people, or those with inflammatory bowel disease and fat malabsorption syndromes (celiac disease and cystic fibrosis) are also at greater risk.
• Deficiency causes rickets (weak, deformed bones) in children, osteomalacia (soft bones) and osteoporosis in adults, dental problems, muscle weakness, and tooth decay.
• Drugs that deplete vitamin D: carbamazepine, phenytoin, phenobarbital, cimeti- dine, ranitidine, cholestyramine, colestipol, orlistat, and mineral oil.
• Since vitamin D is found in few foods and at low amounts, a supplement is recommended for most people. Most multivitamins provide 400 IU (10 mcg). Those with limited sun exposure, osteoporosis, multiple sclerosis, psoriasis, and those over age 65 should consider additional vitamin D.

Vitamin E
• Is an antioxidant (protects cell membranes against oxidative damage; prevents LDL oxidation) that supports immune function, prevents blood clotting, and dilates blood vessels.
• Used to prevent and treat heart disease, cancer, macular degeneration, and cata- racts, enhance immune response, reduce oxidative stress, and improve cognitive function.
• Deficiency is rare, except in those who are malnourished or who have fat-malabsorption conditions (celiac disease, cystic fibrosis); however, suboptimal intake is common and associated with increased risk of heart disease.
• Symptoms of deficiency include impaired balance and coordination, damage to sensory nerves (peripheral neuropathy), muscle weakness (myopathy), and damage to the retina of the eye (pigmented retinopathy).
• Drugs that deplete vitamin E: cholestyramine, colestipol, isoniazid, mineral oil, orlistat, sucralfate, phenobarbitol, phenytoin, and carbamazepine.
• Vitamin E may enhance the blood thinning effects of warfarin.
• It is difficult to achieve the RDA from diet alone; supplements are particularly necessary to achieve amounts needed for disease prevention.
• Look for natural vitamin E (alpha-tocopherol); the synthetic form (dl-alphatocopherol) is less bioavailable (i.e., less absorbable) and only half as potent.

Vitamin K
• Essential for blood clotting; required for bone formation and cell growth.
• Useful in the prevention of osteoporosis.
• Deficiency is rare in adults and causes impaired blood clotting; it is more common in newborns and can cause severe bleeding. Injections of vitamin K1 are typically given to newborns.
• Symptoms of deficiency include easy bruising and bleeding (nosebleeds, bleeding gums, blood in the urine or stool, or heavy menstrual bleeding).
• Drugs that deplete: antibiotics, aspirin, phenytoin, phenobarb, cholestyramine, colestipol, orlistat, and mineral oil.
• High intake of vitamin K from foods or supplements can reduce the efficacy of blood-thinning drugs (warfarin).
• Most people get adequate vitamin K from the diet and/or a multivitamin.

MINERALS, TRACE MINERALS, AND ELECTROLYTES
Minerals are elements that originate in the earth. The body cannot make minerals so they must be obtained through the diet and/or supplements. Both plant and animal foods provide minerals. Plants obtain minerals from the soil they are grown in. Animals get minerals from the plants they eat, and then we get these minerals indirectly by eating the animal products. There are also some minerals present in drinking water, but this varies with geographic location, as does the mineral content of plants.
Minerals are categorized according to our daily requirements. Calcium, magne- sium, and phosphorus are considered major minerals since we require a substantial amount of these for health and wellness. The trace minerals, which are required in smaller amounts, are chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium, and zinc. The minerals potassium and sodium are known as electrolytes, substances that dissociate into ions (charged particles) in solution, making them capable of conducting electricity.

MINERALS Calcium
• The most abundant mineral in the body; essential for building and maintaining bones
and teeth; required for muscle contractions and nerve function; regulates blood pressure, blood vessel contractions, and clotting; involved in enzyme reactions.
• Used for the prevention of osteoporosis, colorectal cancer, pre-eclampsia, and lead toxicity and the treatment of high blood pressure.
• Deficiency can occur with poor diet, abnormal parathyroid function (gland that regulates blood calcium levels), kidney failure, and vitamin D or magnesium deficiency.
• Symptoms of deficiency include bone loss and weakening, muscle cramps, heart palpitations, tooth decay, back and leg pain, insomnia, nervous disorders, and rickets (bone deformities in children).
• Drugs that deplete calcium: cimetidine, ranitidine, omeprazole, aluminum antacids, corticosteroids, cholestyramine, mineral oil, phenytoin, and furosemide.
• A high intake of sodium (salt), protein, phosphorus (soft drinks and food addi- tives), or caffeine (more than 2 cups of coffee or 300 mg caffeine per day) can promote calcium losses.
• Calcium supplements may reduce the efficacy of calcium channel blockers (drugs used to lower blood pressure); use with thiazide diuretics increases the risk of hypercalcemia (high blood calcium levels); calcium supplements may reduce absorption of antibiotics (tetracycline, quinolones), bisphosphonates (osteoprosis drugs), and levothyroxine (thyroid hormone).
• It is difficult to meet the RDA through diet alone unless dairy intake is high. Most multivitamin/mineral supplements provide a small amount of calcium because it is quite bulky. Therefore, a separate calcium supplement may be necessary, especially for those at risk of osteoporosis and those with high blood pressure.
• There are several forms of calcium: Carbonate provides the highest amount of cal- cium (40 percent) and is inexpensive; citrate provides 21 percent calcium, but may be better absorbed in the elderly and those taking acid lowering drugs.
• To maximize absorption, take no more than 500 mg of elemental calcium at one time, take with meals, and ensure adequate vitamin D intake (as this is required for calcium absorption).
• Separate calcium rich foods and supplements by two hours from iron supplements (calcium reduces iron absorption); avoid drinking tea with meals, as the tannins in tea reduce calcium absorption.
• Some vegetables contain chemicals that inhibit the absorption of calcium, such as oxalic acid, which is found in raw spinach, rhubarb, sweet potato, and dried beans. Cooking these foods releases calcium that is bound to oxalic acid, thus improving the amount you can absorb. Phytic acid, which is found in wheat bran or dried beans, also reduces calcium absorption.
Magnesium
• Required for nerve and muscle function, formation of bones and teeth, synthesis of the antioxidant glutathione, cell membranes, and body temperature regulation; involved in energy production, numerous enzyme reactions, and synthesis of DNA and RNA.
• Used to prevent heart disease and in the treatment of high blood pressure, pre-eclampsia, heart disease, diabetes, osteoporosis, migraine headaches, and asthma.
• Deficiency is uncommon, but may occur in those with poor diets, malabsorption syndromes (celiac disease), Crohn’s disease, intestinal surgery or inflammation, kidney disease, diabetes, alcoholism, and in the elderly due to reduced absorption.
• Marginal deficiency (consuming less than the RDA) is common and is estimated to affect 75 percent of people.
• Symptoms of deficiency: muscle cramps and spasms, weakness, insomnia, poor appetite, kidney stones, osteoporosis, nervousness, irritability, anxiety, depression, and high blood pressure.
• Drugs that deplete magnesium: furosemide, hydrochlorothiazine, cholestyramine, and oral contraceptives.
• Other interactions: Magnesium reduces absorption of digoxin, nitrofurantoin, anti malarial drugs, quinolone antibiotics, tetracycline, chlorpromazine, alendronate, and etidronate, so separate intake of magnesium from these foods by two hours.
• High doses of zinc (greater than140 mg/day) reduce magnesium absorption.
• It is difficult to meet the RDA through diet alone; therefore, a multivitamin/mineral supplement is recommended. Certain individuals may require an additional magnesium supplement.

Phosphorus
• Required for structure of bones, teeth, soft tissue, and cell membranes (phospho- lipids); energy production and storage; enzyme reactions; hormones; formation of DNA and RNA; and maintaining acid-base balance.
• Deficiency is rare except among alcoholics and those with kidney disease, malabsorption syndromes (celiac or Crohn’s disease), or poor diets.
• Symptoms of deficiency: poor appetite, anemia, muscle weakness, bone pain, rickets in children, osteomalacia in adults, increased risk of infection, and numbness and tingling of extremities.
• Drugs that deplete phosphorus: aluminum and magnesium (antacids and supplements), cholestyramine, and digoxin.
• Most people get adequate phosphorus through diet; supplements are rarely necessary.

TRACE MINERALS Chromium
• Involved in glucose metabolism (enhances effect of insulin) and enzyme reactions.
• Used for diabetes and for those with impaired glucose tolerance and to lower cholesterol and triglycerides.
• Severe deficiency is rare, but marginal deficiency is common; it is estimated that 90 percent of adults consume less than the RDA.
• The main cause of deficiency is poor dietary intake (high-sugar diets increase urinary excretion of chromium).
• Deficiency results in impaired glucose utilization and may be a contributing factor to the development of type 2 diabetes; symptoms include elevated blood sugar, numbness, and tingling in the extremities and nerve problems.
• Drugs that deplete chromium: corticosteroids (prednisone).
• Other interactions: Chromium may enhance the blood sugar lowering effects of insulin and oral drugs (glyburide and metformin), thus requiring a dosage adjustment.
• Since marginal deficiencies are common, a multivitamin/mineral complex containing chromium is recommended. Chromium is available in several forms. Most studies involving chromium were done with the picolinate form, which is readily absorbed and utilized by the body. Certain individuals (diabetics and those at risk for diabetes) may require an additional supplement.

Copper
• A component of enzymes, which are required for energy production, connective tissue formation, iron metabolism, brain and nervous system, synthesis of neu- rotransmitters, melanin, myelin, hemoglobin, and the antioxidant superoxide dismutase; involved in regulating gene expression.
• Severe deficiency is rare, but marginal deficiencies are common. The typical diet provides about 50 percent of the RDA. Others at risk: Premature and low birth- weight infants with diarrhea; infants fed only cow’s milk formula, which is low in copper; those with malnutrition, malabsorption syndromes (celiac disease), cystic fibrosis, and those receiving intravenous feeding.
• Deficiency leads to iron deficiency and anemia, low white blood cell count (increased risk of infection), osteoporosis, loss of skin pigment, and impaired growth in children.
• Drugs that deplete copper: penicillamine, ethambutol, and zidovudine.
• Other interactions: Prolonged high doses of zinc (50 mg daily or more) may result in copper deficiency.
• A varied diet provides adequate copper for most individuals. In addition, taking a
multivitamin/mineral complex will provide the RDA.

Fluoride
• Essential for formation of healthy bones and teeth.
• Used to prevent cavities, harden tooth enamel, and strengthen bones (prevent osteoporosis).
• Deficiency causes tooth decay and dental caries (cavities).
• Drugs that deplete fluoride: Calcium supplements and calcium- and aluminium containing antacids reduce fluoride absorption (separate intake of fluoride from these by two hours).
• Supplements are available by prescription and are recommended only for children
living in areas with low water fluoride concentrations; rarely required for adults.
• People who consume well water should have the fluoride content of their water tested.

Iodine
• Required to make thyroid hormones, which regulate metabolism, energy production, and body temperature, and are essential for growth and reproduction.
• Used for prevention of radiation-induced thyroid cancer in those with iodine deficiency and to treat fibrocystic breast disease.
• Deficiency may occur in those who do not consume salt, fish, or sea vegetables and is becoming more common in the general population due to restrictions on salt intake for blood pressure.
• Deficiency reduces thyroid hormone production, causing hypothyroidism, fatigue, weight gain, goiter, miscarriage, birth defects, and stunted growth. It is also the most common cause of brain damage worldwide.
• Drugs that deplete iodine: potassium iodide, possibly resulting in hypothyroidism.
• Other interactions: Amiodarone (heart drug) contains high levels of iodine and may affect thyroid function; potassium iodide may decrease the anticoagulant effect of warfarin.
• A deficiency of selenium, vitamin A, or iron can worsen iodine deficiency.
• Foods containing goitrogens—such as cabbage, broccoli, cauliflower, Brussels sprouts, and soybeans inhibit the synthesis of thyroid hormone. These foods are a concern only for those who are iodine deficient and consume high amounts of them. Cooking deactivates the goitrogens.
• Supplements are rarely necessary, but should be considered in pregnant and lactating women if dietary iodine is insufficient to meet the RDA.
• A daily prenatal supplement providing 150 mcg of iodine will help to ensure that pregnant and breast feeding women consume sufficient iodine during these critical periods.

Iron
• Required to produce hemoglobin and myoglobin (proteins involved in the transport and storage of oxygen) and amino acids (carnitine); required for cellular energy production; produces enzymes that have antioxidant effects; supports DNA synthesis and immune function.
• Used for prevention of anemia in pregnancy and in others at risk, and in the treatment of restless legs syndrome.
• Deficiency is common, especially in women with heavy menstrual bleeding and during pregnancy (increased needs for baby), vegetarians, and those with malabsorption syndromes (celiac disease), bleeding ulcers, copper deficiency, and in surgery.
• Deficiency leads to depleted iron stores, impaired red blood cell formation, and anemia. Symptoms include fatigue, paleness, headache, hair loss, brittle nails, rapid heart rate, increased risk of infections, and rapid breathing on exertion.
• Drugs that deplete iron: antacids, cimetidine, ranitidine, omeprazole, lansoprazole, aspirin, anti-inflammatory drugs, and cholestyramine.
• Iron supplements can bind to and reduce absorption and efficacy of levodopa, levothyroxine, methyldopa, quinolones, tetracyclines, bisphosphonates, and zinc and calcium supplements. To avoid this, separate intake of iron supplements from these products by two hours.
• Vitamin C-rich foods and supplements enhance the absorption of nonheme iron (form of iron found primarily in plants).
• A multivitamin/mineral complex providing the RDA is recommended for most pre-menopausal and pregnant women and those at risk of deficiency.
• Men and post-menopausal women should choose iron free multivitamin/mineral supplements to avoid iron excess.

Manganese
• Required for the production and activation of enzymes that are involved in energy metabolism; bone, cartilage, and collagen formation; and the production of antioxidants.
• Deficiency is uncommon, but may occur in those with epilepsy, hypoglycemia, dia- betes, schizophrenia, and osteoporosis.
• Deficiency symptoms: impaired growth and reproductive function, skeletal abnormalities, impaired glucose tolerance, and altered carbohydrate and fat metabolism.
• Drugs that deplete: magnesium-containing antacids and laxatives and tetracycline.
• Absorption is reduced by calcium, phosphate, and iron.
• Supplements beyond the amount provided by diet and/or a multivitamin and mineral complex are not necessary.

Molybdenum
• Required for the production of enzymes that are cofactors in amino acid metabolism, formation of uric acid, and the metabolism of drugs and toxins.
• Deficiency is extremely rare and may occur in those with a rare genetic condition; deficiency causes seizures, developmental delays in neonates, tachycardia, brain damage, and coma.
• Drugs that deplete: high intakes of copper or sulphate.
• Supplements beyond the amount provided by diet and/or a multivitamin and mineral complex are not necessary.

Selenium
• Component of enzymes that function as antioxidants; involved in detoxification; converts thyroid hormone to its active form; supports immune function; enhances the antioxidant activity of vitamin E.
• Used to strengthen immune function and prevent infection, to protect against colon and prostate cancer, and to prevent oxidative stress and support immune system function in those with HIV/AIDS.
• Deficiency is uncommon, but may occur in those with poor diets, those who live in areas where the soil is depleted in selenium, Crohn’s disease, and malabsorption syndromes (celiac disease).
• Symptoms of deficiency: muscular weakness and wasting, cardiomyopathy (inflam- mation of the heart), pancreatic damage, and impaired immune function.
• Drugs that deplete: valproic acid and corticosteroids (prednisone).
• Supplements beyond the amount provided by diet and/or a multivitamin and mineral complex may be necessary for some individuals.

Zinc
• Involved in numerous enzyme reactions; required for growth and development, immune and neurological function, reproduction and regulation of gene expression; stabilizes the structure of proteins and cell membranes.
• Used to support immune function, reduce severity and duration of the common cold, and delay the progression of macular degeneration.
• Severe deficiency is rare, except in those with a genetic disorder, severe malnutrition or malabsorption, severe burns, or chronic diarrhea.
• Marginal deficiencies are common in malnourished people, vegetarians, pregnant women, the elderly, and those with celiac disease, Crohn’s disease, colitis, and sickle cell anemia.
• Symptoms of deficiency include impaired growth and development, skin rashes, severe diarrhea, immune system deficiencies, impaired wound healing, poor appetite, impaired taste sensation, night blindness, clouding of the corneas, and behavioural disturbances.
• Drugs that deplete: diuretics, anticonvulsants, iron supplements, penicillamine, ACE-inhibitor drugs, acid reducing drugs, and oral contraceptives.
• Zinc supplements can reduce copper levels, so look for a multivitamin that contains copper as well as zinc.
• Zinc supplements can reduce absorption of antibiotics (tetracycline and quinolones), so separate intake of zinc supplements from these products by two hours.
• Since the average zinc intake is below the RDA and many conditions and drugs deplete zinc levels, a supplement should be considered. Most multivitamin and mineral complexes provide at least the RDA for zinc.

ELECTROLYTES Potassium
• Required to maintain fluid balance; required for nerve conduction and muscle function; cofactor for enzymes involved in energy production and carbohydrate metabolism.
• Used for prevention of stroke, osteoporosis, kidney stones, and in the treatment of high blood pressure.
• Deficiency (hypokalemia) is common and caused by prolonged diarrhea or vomiting, alcoholism, kidney failure, laxative abuse, anorexia, or magnesium deficiency.
• Deficiency symptoms include fatigue, muscle weakness and cramps, bloating, constipation, and abdominal pain. Severe hypokalemia may result in muscular paralysis or abnormal heart rhythms.
• Drugs that deplete: furosemide, hydrochlorothiazide, corticosteroids, pseudoephedrine, caffeine, and high dose penicillin.
• Drugs that enhance potassium (may cause hyperkalemia): Spironolactone, triamterene, amiloride, ACE-inhibitors, anti-inflammatory drugs (ibuprofen), heaparin, digoxin, and beta-blockers.
• The average dietary potassium intake is about 2,300 mg/day for women and 3,100mg/day for men. Evidence suggests that diets supplying at least 4,700 mg per day are associated with a decreased risk of stroke, hypertension, osteoporosis, and kidney stones, and this is the AI level set by the Institute of Medicine.
• Multivitamin/mineral complexes typically provide 99 mg of potassium per serving. Depending on dietary intake and personal risk factors, additional potassium supplements may be necessary for some people.
• Take supplements with meals or choose a microencapsulated form to reduce the risk of upset stomach.

Sodium
• Regulates fluid balance along with potassium; required for nerve conduction and muscle function; assists absorption of chloride, amino acids, glucose, and water; regulates blood volume and blood pressure.
• Excess sodium intake is linked to gastric cancer, osteoporosis, high blood pressure, and kidney stones. Reducing sodium intake may help to reduce the risk of these conditions.
• Deficiency is rare; low blood levels of sodium (hyponatremia) may be caused by fluid retention or excess sodium loss (excessive sweating, prolonged exercise, severe and prolonged vomiting and diarrhea, and kidney disease).
• Symptoms of hyponatremia include headache, nausea, muscle cramps, fatigue, confusion, and fainting. Severe cases may lead to swelling of the brain, seizures, coma, and brain damage.
• Drugs that deplete sodium: diuretics, anti-inflammatory drugs, carbamazepine, codeine, morphine, and some antidepressants.
• Supplements are rarely necessary, except in the above mentioned conditions.
• The AI level for sodium and sodium chloride (salt) is based on the amount needed to replace losses through sweat in moderately active people and to achieve a diet that provides sufficient amounts of other essential nutrients. Most adults consume
an amount much greater than the AI.

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