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Vitamins
Vitamin A prevents night blindness and other eye problems, as well as some skin disorders, such as acne. It enhances immunity, may help to heal gastrointestinal ulcers, and is needed for the maintenance and repair of epithelial tissue, of which the skin and mucous membranes are composed. It is important in the formation of bones and teeth, aids in fat storage, and protects against colds, flu, and in-factions of the kidneys, bladder, lungs, and mucous membranes. Vitamin A acts as an antioxidant, helping to protect the cells against cancer and other diseases and is necessary for new cell growth. It guards against heart disease and stroke, and lowers cholesterol levels. This important vitamin also slows the aging process. Protein cannot be utilized by the body without vitamin A. Vitamin A is a well-known wrinkle eliminator. Applied topically in the form of tretinoin (the active ingredient in Retin-A and Renova), vitamin A reduces fine lines in the skin and helps fade age spots. What is the importance of vitamin A? Vitamin A, a fat-soluble vitamin, plays essential roles in vision, growth, and development; the development and maintenance of healthy skin, hair, and mucous membranes; immune functions; and reproduction. A deficiency of vitamin A can cause dry hair and/or skin, dryness of the conjunctiva and cornea, poor growth, and/or night blindness. Other possible results of vitamin A deficiency include abscesses in the ears; insomnia; fatigue; reproductive difficulties; sinusitis, pneumonia, and frequent colds and other respiratory infections; skin disorders, including acne; and weight loss. What are carotenoids? The carotenoids are a class of compounds related to vitamin A. In some cases, they can act as precursors of vitamin A; some act as antioxidants or have other important functions. The best known subclass of the carotenoids are the carotenes, of which beta-carotene is the most widely known. Also included in this group are alpha- and gamma-carotene, and lycopene. When food or supplements containing beta-carotene are consumed, the beta-carotene is converted into vitamin A in the liver. According to recent reports, beta-carotene appears to aid in cancer prevention by scavenging, or neutralizing, free radicals. Other types of carotenoids that have been identified are the xanthophylls (including beta-cryptoxanthin, canthaxanthin, lutein, and zeaxanthin): the limonoids (including limnnene); and the phytosterols (including perillyl alcohol). Science has not yet discovered all of the carotenoids, although one source documents 563 different carotenoids identified so far. Combinations of carotenoids have been shown to be more beneficial than individual carotenoids taken alone. How much do you need? Vitamin A is also called retinol. Measurement of the amount of vitamin A is taken in retinol activity equivalents (RAE). Carotene, an orange pigment found in food, is split by the body to become two active units of vitamin A. This is also important when calculating the amount of vitamin A in the body. The U.S. Recommended Daily Allowance (RDA) for vitamin A is 700 RAE per day for women and 900 RAE per day for men. The U.S. RDA given is for adults and changes for women who are pregnant or lactating; therefore, please consult your healthcare provider for differences. A good source of vitamin A contains substantial amounts of vitamin A and/or carotene in relation to its calorie content and contributes at least 10% of the U.S. RDA for vitamin A in a serving. How to get enough vitamin A. Eating a variety of foods that contain vitamin A (and carotene) is the best way to get an adequate amount. Healthy individuals who eat a balanced diet rarely need supplements. In fact, too much vitamin A can be toxic. Select foods that contain excellent to good sources of vitamin A each day. Vitamin A can be found in animal livers, fish liver oils, and green and yellow fruits and vegetables. Foods that contain significant amounts include apricots, asparagus, beet greens, broccoli, cantaloupe, carrots, collards, dandelion greens, dulse, fish liver and fish liver oil, garlic, kale, mustard greens, papayas, peaches, pumpkin, red peppers, spinach, spirulina, sweet potatoes, Swiss chard, turnip greens, watercress, and yellow squash. It is also present in the following herbs: alfalfa, borage leaves, burdock root, cayenne (capsicum), chickweed, eyebright, fennel seed, hops, horsetail, kelp, lemongrass, mullein, nettle, oat straw, paprika, parsley, peppermint, plantain, raspberry leaf, red clover, rose hips, s age, uva ursi, violet leaves, watercress, and yellow dock. Animal sources of vitamin A are up to six times as strong as vegetable sources.   How to prepare foods to retain vitamin A. Vitamin A can be lost from foods during preparation, cooking, or storage. To prevent loss of vitamin A: Use raw fruits and vegetables whenever possible. Keep vegetables (except sweet potatoes and winter squash) and fruits covered and refrigerated during storage. Steam vegetables and braise, bake, or broil meats instead of frying. Some of the vitamin A is lost in the fat during frying. What about fortified foods? Low-fat and skim milk are often fortified with vitamin A because it is lost during processing. Margarine is fortified to make its vitamin A content the same as butter. Most ready-to-eat and instant prepared cereals are fortified with vitamin A. Fortified ready-to-eat cereals usually contain at least 25% of the U.S. RDA for vitamin A. Cereals vary, so check the label on the package for the vitamin A content for that cereal. What is a serving? The amount of vitamin A in a serving depends on the weight of the serving. For example, ½ cup of a cooked vegetable contains more vitamin A than ½ cup of the same vegetable raw, because the cooked vegetable weighs more. Therefore, the cooked vegetable provides vitamin A, just not enough in a ½-cup serving to be considered a good source. Food companies label their products according to regulations set by the Food and Drug Administration (FDA). Terms to define a serving of food that has 20% or more of the RDA include: “high,” “rich in,” or “excellent source of” vitamin A. Terms to define a serving of food that contains 10% or more of the RDA include: “good,” “contains or provides” vitamin A. Terms to define a serving of food that contains less then 10% of the RDA include: “enriched,” “fortified,” or “added” vitamin A. What precautions must I take? Taking large amounts of vitamin A, over 100,000 international units daily, over long periods can be toxic to the body, mainly the liver. Toxic levels of vitamin A are associated with abdominal pain, amenorrhea (cessation of menstruation), enlargement of the liver and/or spleen, gastrointestinal disturbances, hair loss, itching, joint pain, nausea and vomiting, water on the brain, elevated liver enzymes, and small cracks and scales on the lips and at the corners of the mouth. Excessive intake of vitamin A during pregnancy has been linked to birth defects, including cleft palate and heart defects. It is better to take beta-carotene during pregnancy. If you have a particular disorder that calls for taking high doses of vitamin A, use an emulsified form, which puts less stress on the liver. Antibiotics, laxatives, and some cholesterol-lowering drugs interfere with the absorption of vitamin A. If you have liver disease, do not take a daily dose of over 10,000 international units of vitamin A in pill form, or any amount of cod liver oil. If you are pregnant, do not take more than 10,000 international units of vitamin A daily because of reported problems in fetal development. Children should not take more than 18,000 international units of vitamin A on a daily basis for over one month. For most people, beta-carotene is the best source of vitamin A because it is converted by the liver into only the amount of vitamin A that the body actually needs. However, if you have diabetes or hypothyroidism, there is a good possibility your body cannot convert beta-carotene into vitamin A. Consuming large amounts of beta-carotene may therefore place unnecessary stress on your liver. Suggested Reading:
Thiamine enhances circulation and assists in blood formation, carbohydrate metabolism, and the production of hydrochloric acid, which is important for proper digestion. Thiamine also optimizes cognitive activity and brain function. It has a positive effect on energy, growth, normal appetite, and learning capacity, and is needed for proper muscle tone of the intestines, stomach, and heart. Thiamine also acts as an antioxidant, protecting the body from the degenerative effects of aging, alcohol consumption, and smoking. What are the symptoms of deficiency? Early symptoms are vague. They include fatigue, irritability, memory impairment, loss of appetite, sleep disturbances, abdominal discomfort, and weight loss. Eventually, a severe vitamin B1 deficiency (beriberi) may develop, characterized by nerve, heart, and brain abnormalities. Beriberi causes different symptoms in different people. One form, called dry beriberi, causes nerve and muscle abnormalities. Symptoms include a prickling (pins-and-needles) sensation in the toes, a burning sensation in the feet that is particularly severe at night, and pain, weakness, and wasting (atrophy) of muscles in the legs. Wet beriberi causes heart abnormalities. Symptoms include a high output of blood from the heart, a fast heart rate, and dilation of blood vessels, causing the skin to be warm and moist. Because the heart cannot maintain the high output, heart failure eventually develops, causing fluid accumulation in the legs (edema) and in the lungs (congestion). As a result, blood pressure may fall, leading to shock and death. Brain abnormalities due to vitamin B1 deficiency occur primarily in alcoholics. Brain abnormalities may develop when a chronic vitamin B1 deficiency is suddenly worsened by a rapid, substantial decrease in the vitamin B1 level (which can be caused by an alcoholic binge) or by a sudden increase in vitamin B1 requirements (which may occur when an undernourished alcoholic is fed intravenously). Brain abnormalities may develop in two stages: an early stage called Korsakoff's syndrome and a later stage called Wernicke's encephalopathy. Together, these stages are called the Wernicke-Korsakoff syndrome. Korsakoff's syndrome causes memory loss, and Wernicke's encephalopathy causes mental confusion, difficulty walking, and eye problems (including nystagmus and paralysis of the eyes). If Wernicke's encephalopathy is not promptly treated, symptoms may worsen, resulting in coma and even death. Wernicke's encephalopathy, a medical emergency, is treated with high doses of vitamin B1 for several days. When people who may be alcoholics must be fed intravenously, they are often given vitamin B1 supplements as a preventive measure. For people who have the Wernicke-Korsakoff syndrome, recovery is often incomplete because some brain damage may be permanent. Symptoms of beriberi may recur years after apparent recovery. How to get enough vitamin B1 The richest food sources of thiamine include brown rice, egg yolks, fish, legumes, liver, peanuts, peas, pork, poultry, rice bran, wheat germ, and whole grains. Other sources are asparagus, brewer's yeast, broccoli, Brussels sprouts, dulse, kelp, most nuts, oatmeal, plums, dried prunes, raisins, spirulina, and watercress. Herbs that contain thiamine include alfalfa, bladderwrack, burdock root, catnip, cayenne, chamomile, chickweed, eyebright, fennel seed, fenugreek, hops, nettle, oat straw, parsley, peppermint, raspberry leaf, red clover, rose hips, sage, yarrow, and yellow dock. What precautions must I take? Antibiotics, phenytoin (Dilantin, a drug used to prevent seizures), sulfa drugs, and oral contraceptives, and heavy alcohol or caffeine consumption may decrease thiamine levels in the body. A high-carbohydrate diet increases the need for thiamine. Alcoholics are among those most often deficient in thiamine. Suggested Reading:
Riboflavin is necessary for red blood cell formation, antibody production, cell respiration, and growth. It alleviates eye fatigue and is important in the prevention and treatment of cataracts. It aids in the metabolism of carbohydrates, fats, and proteins. Together with vitamin A, it maintains and improves the mucous membranes in the digestive tract. Riboflavin also facilitates the use of oxygen by the tissues of the skin, nails, and hair; eliminates dandruff; and helps the absorption of iron and vitamin B6 (pyridoxine). Consumption of adequate amounts of riboflavin is important during pregnancy, because a lack of this vitamin can damage a developing fetus even if a woman shows no signs of deficiency. Riboflavin is needed for the metabolism of the amino acid tryptophan, which is converted into niacin in the body. Carpal tunnel syndrome may benefit from a treatment program that includes riboflavin and vitamin B6. Deficiency symptoms include cracks and sores at the corners of the mouth, eye disorders, inflammation of the mouth and tongue, and skin lesions, a group of symptoms collectively referred to as ariboflavinosis. Other possible deficiency symptoms include dermatitis, dizziness, hair loss, insomnia, light sensitivity, poor digestion, retarded growth, and slowed mental response. Sources The best sources of riboflavin include brewer's yeast, almonds, organ meats, whole grains, wheat germ, wild rice, mushrooms, soybeans, milk, yogurt, eggs, broccoli, brussel sprouts, and spinach. Flours and cereals are often fortified with riboflavin. Other sources include asparagus, avocados, currants, dandelion greens, dulse, kelp, leafy green vegetables, mushrooms, molasses, nuts, and watercress. Herbs that contain vitamin 82 include alfalfa, bladderwrack, burdock root, catnip, cayenne, chamomile, chickweed, eyebright, fennel seed, fenugreek, ginseng, hops, horsetail, mullein, nettle, oat straw, parsley, peppermint, raspberry leaves, red clover, rose hips, sage, and yellow dock. Riboflavin is destroyed by light; therefore, items should be stored away from the light to protect their riboflavin content. This is the reason that many dairy companies switched from glass milk bottles to cartons and opaque containers. While riboflavin is not destroyed by heat, it can be lost in water when foods are boiled or soaked. Available Forms Riboflavin is generally included in multivitamin preparations and in B-complex vitamins, and comes individually in 25-, 50-, and 100-mg tablets. Recommended dose Pediatric
Factors that increase the need for riboflavin include the use of oral contraceptives and strenuous exercise. This B vitamin is easily destroyed by light, antibiotics, and alcohol. Taking too much riboflavin (over 50 milligrams daily) over a long period of time may lead to cataracts and retinal diseases. Absorption of Vitamin B2 is best when it is taken with meals. Riboflavin does not appear to cause any serious side effects. Possible reactions to very high doses may include itching, numbness, burning or prickling sensations, and sensitivity to light. Taking any one of the B complex vitamins for a long period of time can result in an imbalance of other important B vitamins. For this reason, it is generally important to take a B complex vitamin with any single B vitamin. Possible Interactions If you are currently being treated with any of the following medications, you should not use vitamin B2 supplements without first talking to your healthcare provider. Antibiotics, Tetracycline Riboflavin should not be taken at the same time as the antibiotic tetracycline because it interferes with the absorption and effectiveness of this medication. Riboflavin either alone or in combination with other B vitamins should be taken at different times from tetracycline. (All vitamin B complex supplements act in this way and should therefore be taken at different times from tetracycline.) In addition, long-term use of antibiotics can deplete vitamin B levels in the body, particularly B2, B9, B12, and vitamin H (biotin), which is considered part of the B complex. Antidepressant Medications Tricyclic antidepressants (such as imipramine, desimpramine, amitriptyline, and nortriptyline) also reduce levels of riboflavin in the body. Taking riboflavin may improve levels of the vitamin and improve the effectiveness of these antidepressants, especially in elderly patients. Anti-malarial Medications Riboflavin may reduce the effectiveness of anti-malarial medications such as chloroquine and mefloquine. Antipsychotic Medications Antipsychotic medications called phenothiazines (such as chlorpromazine) may lower riboflavin levels. Birth Control Medications Poor dietary habits in combination with birth control medications can interfere with the body's ability to use riboflavin. Doxorubicin In the presence of daylight, riboflavin may deactivate doxorubicin, a medication used for the treatment of certain cancers. In addition, doxorubicin may deplete levels of riboflavin and, therefore, increased amounts of this nutrient may be recommended during chemotherapy using this drug. Your doctor will guide you on whether this is necessary or not. Methotrexate Methotrexate, a medication used to treat cancer, can prevent the body from making riboflavin (as well as other essential vitamins). Phenytoin Phenytoin, a medication used to control epileptic seizures, may affect riboflavin levels in children. Probenecid This medication used for gout may decrease the absorption of riboflavin from the digestive tract and increase the excretion in the urine. Selegiline Similar to its effects on doxorubicin, riboflavin may deactivate selegiline, a medication used to treat Parkinson's disease, in the presence of daylight. Sulfa-containing Medications Riboflavin may reduce the effectiveness of sulfa-containing medications, such as certain antibiotics (for example, trimethoprim-sulfamethoxazole) used to treat bacterial infections. In addition, as stated earlier, long-term use of antibiotics can deplete vitamin B levels in the body, particularly B2, B9, B12, and vitamin H (biotin), which is considered part of the B complex. Thiazide Diuretics Diuretics that belong to a class known as thiazides, such as hydrochlorothiazide, may increase the loss of riboflavin in the urine. Suggested Reading:
Vitamin B3 is needed for proper circulation and healthy skin. It aids in the functioning of the nervous system; in the metabolism of carbohydrates, fats, and proteins; and in the production of hydrochloric acid for the digestive system. It is involved in the normal secretion of bile and stomach fluids, and in the synthesis of sex hormones. Niacin lowers cholesterol and improves circulation. It is helpful for schizophrenia and other mental illnesses, and is also a memory-enhancer. Pellagra is a disease caused by niacin deficiency. Other symptoms of niacin deficiency include canker sores, dementia, depression, diarrhea, dizziness, fatigue, halitosis, headaches, indigestion, insomnia, limb pains, loss of appetite, low blood sugar, muscular weakness, skin eruptions, and inflammation. Uses High Cholesterol Niacin is commonly used to lower elevated LDL ("bad") cholesterol and triglyceride (fat) levels in the blood and is more effective in increasing HDL ("good") levels than other cholesterol-lowering medications. However. High doses of niacin produce the side effects of flushing of the skin (which can be reduced by taking aspirin 30 minutes before the niacin), stomach upset (which usually subsides in a few weeks), headache, dizziness, blurred vision, and liver damage. Although the time-release form of niacin reduces flushing, long-term use is associated with liver damage. Atherosclerosis High doses of niacin medications are used to prevent development of atherosclerosis (plaque along the blood vessels that can cause blockage) and to reduce recurrent complications such as heart attack and peripheral vascular disease (atherosclerosis of the blood vessels in the legs that can cause pain with walking, called intermittent claudication) in those with the condition. According to a review of major clinical trials, the use of niacin for prevention and treatment of atherosclerosis and related conditions is "based on strong and consistent evidence" and appears to be as effective as certain medications for heart disease. Studies also suggest that high dose niacin may help relieve the symptoms of claudication – namely diminish the pain experienced with walking. A recent study also found that the combination of niacin and a cholesterol-lowering drug called simvastatin (which belongs to a class known as HmG CoA reductase inhibitors or statins) may dramatically slow the progression of heart disease, reducing risk of heart attack, and even death. Diabetes Because diabetes is often associated with atherosclerosis and heart disease, people with diabetes may benefit from nutrients that help manage elevated cholesterol levels and high blood pressure. Although niacin has been shown to boost HDL cholesterol and decrease triglyceride and LDL levels, there has been some concern that it may also raise blood sugar levels. In a recent study of 125 people with diabetes and 343 people without the condition, high doses of niacin (roughly 3000 mg/day), increased blood sugar in both groups, but hemoglobin A1C (considered a better measure of blood sugar over time) actually decreased in the diabetes group over a 60-week follow-up period. For this reason, if you have diabetes, niacin should only be used under the close monitoring of a qualified health care provider. Osteoarthritis Some preliminary studies suggest that vitamin B3, as niacinamide, may improve arthritis symptoms, including increasing joint mobility and reducing the amount of anti-inflammatory medications needed. Researchers speculate that niacinamide may aid cartilage repair (damage to joint cartilage causes arthritis) and suggest that it may be used safely along with NSAIDs (non-steroidal anti-inflammatory medications) to reduce inflammation. Further research is needed to fully understand how vitamin B3 benefits people with OA and to determine whether the results apply to large numbers of people with the condition. It does appear, however, that niacinamide must be used for at least 3 weeks before the benefits described are seen. Experts also suggest that long-term use (1 to 3 years) may slow the progression of the disease. Cataracts Dietary vitamin B3, along with other nutrients is important for normal vision and prevention of cataracts (damage to the lens of the eye which can lead to cloudy vision.) One study including 2900 people living in Australia found that people who consumed the most protein, vitamin A, and vitamins B1 (thiamine), B2, and B3 (niacin) in their diets were significantly less likely to develop cataracts. A follow-up study also found that many supplemental B complex vitamins (including B12, B9, B3, B2, and B1) exert a protective effect against cataracts. Burns It is especially important for people who have sustained serious burns to obtain adequate amounts of nutrients in their daily diet. When skin is burned, a substantial percentage of micronutrients may be lost. This increases the risk for infection, slows the healing process, prolongs the hospital stay, and even increases the risk of death. Although it is unclear which micronutrients are most beneficial for people with burns, many studies suggest that a multivitamin including the B complex vitamins may aid in the recovery process. Other An interesting area of research currently underway is the use of niacin skin care products as anti-aging agents, for treatment of acne, and, possibly, for prevention of skin cancer. Dermatologists expect that there will be information emerging about topical forms of niacin for these purposes over the next few years. Sources Niacin and niacinamide are found in beef liver, brewer's yeast, broccoli, carrots, cheese, corn flour, dandelion greens, dates, eggs, fish, milk, peanuts, pork, potatoes, tomatoes, wheat germ, and whole wheat products. Herbs that contain niacin include alfalfa, burdock root, catnip, cayenne, chamomile, chickweed, eyebright, fennel seed, hops, licorice, mullein, nettle, oat straw, parsley, peppermint, raspberry leaf, red clover, rose hips, slippery elm, and yellow dock. Available Forms Niacin is available in several different supplement forms: niacinamide, nicotinic acid, and inositol hexaniacinate. The form of niacin that is best tolerated with the least symptoms is inositol hexaniacinate. Niacin is available as a tablet or capsule in both regular and timed-release forms. The timed-release tablets and capsules may have fewer side effects than the regular niacin; however, the timed-release are more likely to cause liver damage and are therefore not recommended for long-term treatment. Regardless of the form of niacin being used, periodic checking of liver function tests is recommended when high-dose (2 – 6 gm per day) of niacin is used. Recommended dose Daily requirements for niacin may be higher for those who have cancer, those who are being treated with isoniazid (for tuberculosis), and people with protein deficiencies. Daily recommendations for niacin from the diet for healthy individuals are listed below. It is important to note, however, that only extremely high doses of niacin (in the range of 1,500 to 3,000 mg per day in divided doses) are helpful for most medical conditions. Such high doses are considered "pharmacologic" and must be prescribed by a qualified healthcare practitioner. The practitioner will instruct you on increasing the amount of niacin slowly, over the course of 4 to 6 weeks, and to take the medicine with meals to avoid stomach irritation. Pediatric
A flush, usually harmless, may occur after the ingestion of niacin supplements; a red rash appears on the skin and a tingling sensation may be experienced as well. Usually, these symptoms last only a few minutes. Taking an aspirin 30 minutes prior to the niacin may help reduce this symptom. There are two forms of this vitamin: niacin (or nicotinic acid) and niacinamide. In the form of niacinamide, it does not cause flushing. However, niacinamide does not have all the same properties of niacin. Specifically, it is not effective for lowering blood cholesterol. At the very high doses used to lower cholesterol and the other conditions mentioned previously, liver damage and stomach ulcers can occur. When taking pharmacologic doses of niacin, your doctor or other healthcare practitioner will periodically check your liver function through a blood test. People with a history of liver disease or stomach ulcers should not take niacin supplements. Those with diabetes or gallbladder disease should do so only under the close supervision of a healthcare provider. Niacin should not be used if you have gout. Taking any one of the B complex vitamins for a long period of time can result in an imbalance of other important B vitamins. For this reason, it is generally important to take a B complex vitamin with any single B vitamin. People who are pregnant or who suffer from diabetes, glaucoma, gout, liver disease, or peptic ulcers should use niacin supplements with caution. Niacin may elevate blood sugar levels. Amounts over 500 milligrams daily may cause liver damage if taken for prolonged periods. Possible Interactions If you are currently being treated with any of the following medications, you should not use niacin without first talking to your healthcare provider. Antibiotics, Tetracycline Niacin should not be taken at the same time as the antibiotic tetracycline because it interferes with the absorption and effectiveness of this medication. Niacin either alone or in combination with other B vitamins should be taken at different times from tetracycline. (All vitamin B complex supplements act in this way and should therefore be taken at different times from tetracycline.) Aspirin Taking aspirin before taking niacin may reduce flushing associated with this vitamin. This should only be done under the advice of a healthcare practitioner. Blood Pressure Medications, Alpha-blockers When niacin is taken with certain blood pressure medications known as alpha-blockers (such as prazosin, doxazosin, and guanabenz), the likelihood of side effects from these medications is increased. Cholesterol-lowering Medications Niacin binds bile-acid sequestrants (cholesterol-lowering medications such as colestipol, colesevelam, and cholestyramine) and may decrease their effectiveness. For this reason, niacin and these medications should be taken at different times of the day. As described earlier, recent scientific evidence suggests that taking niacin with simvastatin (a drug that belongs to a class of cholesterol-lowering medications known as HMG-CoA reductase inhibitors or statins including atorvastatin and lovastatin as well), appears to slow down the progression of heart disease. However, the combination may also increases the likelihood for serious side effects, such as muscle inflammation or liver damage. Diabetes Medications People taking insulin, metformin, glyburide, glipizide, or other medications used to treat high blood sugar levels should monitor their blood sugar levels closely when taking niacin supplements. Isoniazid (INH) INH, a medication used to treat tuberculosis, may deplete levels of niacin and cause a deficiency. Nicotine Patches The use of nicotine patches with niacin may worsen or increase the risk of flushing reactions associated with this vitamin when used medicinally. Suggested Reading:
Known as "the anti-stress vitamin," pantothenic acid plays a role in the production of the adrenal hormones and the formation of antibodies, aids in vitamin utilization, and helps to convert fats, carbohydrates, and proteins into energy. It is required by all cells in the body and is concentrated in the organs. It is also involved in the production of neurotransmitters. This vitamin is an essential element of coenzyme A, a vital body chemical involved in many necessary metabolic functions. Pantothenic acid is also a stamina enhancer and prevents certain forms of anemia. It is needed for normal functioning of the gastrointestinal tract and may be helpful in treating depression and anxiety. A deficiency of pantothenic acid may cause fatigue, headache, nausea, and tingling in the hands. Pantothenic acid is also needed for proper functioning of the adrenal glands. Uses Wound Healing Studies, primarily in test tubes and animals but a few on people, suggest that vitamin B5 supplements may speed wound healing, especially following surgery. This may be particularly true if vitamin B5 is combined with vitamin C. Burns It is especially important for people who have sustained serious burns to obtain adequate amounts of nutrients in their daily diet. When skin is burned, a substantial percentage of micronutrients may be lost. This increases the risk for infection, slows the healing process, prolongs the hospital stay, and even increases the risk of death. Although it is unclear which micronutrients are most beneficial for people with burns, many studies suggest that a multivitamin including the B complex vitamins may aid in the recovery process. High Cholesterol Throughout the past twenty years or so, emerging studies of animals and people have suggested that high doses of pantethine (a stable form of vitamin B5) may improve cholesterol and triglyceride levels in people with high cholesterol with or without other risk factors for heart disease (such as diabetes, obesity, and menopause). The studies to date have included only small numbers of people, but have been encouraging because not only has pantethine lowered cholesterol and triglycerides, it has also increased HDL (the "good" kind of cholesterol). Plus, several of the studies have looked at the use of pantethine in special groups of people, such as adults on dialysis and children with high cholesterol. More research is needed in this area to fully understand what value pantethine may have for treating or preventing high cholesterol. Other related areas that are under current scientific investigation include use of pantethine for heart disease and for weight loss. Arthritis Although not widely studied to date, there may be some benefit to making sure that there is an adequate amount of pantothenic acid in the diet or taking extra vitamin B5 supplements for arthritis. For example, some researchers report that blood levels of pantothenic acid are lower in people with rheumatoid arthritis than those without this condition. A study conducted in 1980 concluded that 2,000 mg/day of calcium pantothenate improved symptoms of rheumatoid arthritis including morning stiffness and pain. Further studies are needed to confirm these findings, however. Similarly, obese patients with osteoarthritis may improve their symptoms if they receive dietary counseling about appropriate intake of vitamin B5 (as well as other nutrients) and weight loss. Sources The following foods contain pantothenic acid: beef, brewer's yeast, eggs, fresh vegetables, kidney, legumes, liver, mushrooms, nuts, pork, royal jelly, saltwater fish, torula yeast, whole rye flour, and whole wheat. Recommended dose Recommended daily intakes of dietary vitamin B5 are listed below: Pediatric
If you are currently being treated with any of the following medications, you should not use vitamin B5 supplements without first talking to your healthcare provider. Antibiotics, Tetracycline Vitamin B5 should not be taken at the same time as the antibiotic tetracycline because it interferes with the absorption and effectiveness of this medication. B vitamins should be taken at different times from tetracycline. (All vitamin B complex supplements act in this way and should therefore be taken at different times from tetracycline.) Suggested Reading:
Pyridoxine is involved in more bodily functions than almost any other single nutrient. It affects both physical and mental health. It is beneficial if you suffer from water retention, and is necessary for the production of hydrochloric acid and the absorption of fats and protein. Pyridoxine also aids in maintaining sodium and potassium balance, and promotes red blood cell formation. It is required by the nervous system and is needed for normal brain function and for the synthesis of the nucleic acids RNA and DNA, which contain the genetic instructions for the reproduction of all cells and for normal cellular growth. It activates many enzymes and aids in the absorption of vitamin B12, in immune system function, and in antibody production. Vitamin B6 plays a role in cancer immunity and aids in the prevention of arteriosclerosis. It inhibits the formation of a toxic chemical called homocysteine, which attacks the heart muscle and allows the deposition of cholesterol around the heart muscle. Pyridoxine acts as a mild diuretic, reducing the symptoms of premenstrual syndrome, and it may be useful in preventing oxalate kidney stones as well. It is helpful in the treatment of allergies, arthritis, and asthma. A deficiency of vitamin B6 can result in anemia, convulsions, headaches, nausea, flaky skin, a sore tongue, and vomiting. Other possible signs of deficiency include acne, anorexia, arthritis, conjunctivitis, cracks or sores on the mouth and lips, depression, dizziness, fatigue, hyperirritability, impaired wound healing, inflammation of the mouth and gums, learning difficulties, impaired memory or memory loss, hair loss, hearing problems, numbness, oily facial skin, stunted growth, and tingling sensations. Carpal tunnel syndrome has been linked to a deficiency of vitamin B6 as well. Uses Heart Dieases Low dietary intake of vitamin B6 is associated with higher risk of having heart disease. This may be related to the fact that vitamin B6, together with vitamin B9 (folic acid) and vitamin B12, help to keep homocysteine levels under control. Homocysteine is an amino acid. Elevated levels of this amino acid are associated with increased risk of heart disease and increased risk of stroke. The American Heart Association recommends, for most people, that enough of these important B vitamins be obtained from the diet, rather than taking extra supplements. Under certain circumstances, however, supplements may be necessary. Such circumstances include elevated homocysteine levels with known heart disease or strong family history of heart disease at a young age. Nausea and Vomiting during pregnancy A recent review of scientific studies concluded that vitamin B6 may help reduce the severity of nausea during early pregnancy. Osteoporosis Keeping bones healthy throughout life depends on getting sufficient amounts of specific vitamins and minerals, including phosphorous, magnesium, boron, manganese, copper, zinc, folate, and vitamins C, K, B6, and B12. Eating Disorders Levels of important nutrients are often quite low in those with anorexia or bulimia. At least 20% of people with anorexia admitted to a hospital for treatment are deficient in vitamins B2 and B6 (pyridoxine). Some research information suggests that as many as 33% of those with an eating disorder could be deficient in vitamins B2 and B6. Dietary changes alone, without additional supplements, can often bring vitamin B levels back to normal. However, extra B2 and B6 may be required (which will be determined by your doctor or nutritionist). Plus, B-complex vitamins may help alleviate stress and reduce symptoms of depression, frequently associated with eating disorders. Burns It is especially important for people who have sustained serious burns to obtain adequate amounts of nutrients in their daily diet. When skin is burned, a substantial percentage of micronutrients may be lost. This increases the risk for infection, slows the healing process, prolongs the hospital stay, and even increases the risk of death. Although it is unclear which micronutrients are most beneficial for people with burns, many studies suggest that a multivitamin including the B complex vitamins may aid in the recovery process. Vitamin B6, along with other members of the B complex, may be of particular importance, given their value in building protein. Protein is necessary to recover from any kind of an injury. In addition, as stated earlier, the amount of B complex needed may increase during times of stress. Depression Studies suggest that vitamin B9 (folate) may be associated with depression more than any other nutrient. Between 15% and 38% of people with depression have low folate levels in their bodies and those with very low levels tend to be the most depressed. Many healthcare providers start by recommending a multivitamin (MVI) that contains folate, and then monitoring the homocysteine levels in the blood to ensure the adequacy of therapy. Elevated homocysteine levels indicate a deficiency of folate even if the levels of folate in the blood are normal. If the MVI alone is not enough to lower homocysteine and improve folate function, the provider may suggest additional folate along with vitamins B6 and B12 to try to bring the homocysteine levels down, thereby eliminating the functional folate deficiency and, hopefully, helping to improve feelings of depression. Premenstrual Syndrome (PMS) A comprehensive review of studies concluded that vitamin B6 may be more effective than placebo in improving symptoms of PMS, particularly depression. Most studies were poorly designed, however. Still, even though the science is not definitive, many healthcare providers and their female patients report improvement in PMS from using vitamin B6. Therefore, how well you respond to vitamin B6 may be very individual. Until more research is completed, talk with your doctor about whether using B6 is appropriate and safe for you. Then, if taking the vitamin, follow your symptoms closely. It can take up to 3 months until any change is noticeable. Diabetes Preliminary evidence suggests that vitamin B6 may help control blood sugar in people with diabetes. In a study of people with diabetes, those who received pyridoxine alpha-ketoglutarate (a form of vitamin B6) for one month experienced significant reductions in fasting blood sugar levels compared to those who did not receive the supplement. More research in this area is needed before conclusions can be drawn about the relationship between vitamin B6 and diabetes. Human Immunodeficiency Virus (HIV) Vitamin B6, particularly together with a complete B complex, may help alleviate the stress associated with having HIV or AIDS. Attention Deficit/Hyperactive Disorder (ADHD) Adequate levels of vitamin B6 are required for normal brain development and are essential for the synthesis of essential brain chemicals including serotonin, dopamine and norepinephrine. A preliminary study found that pyridoxine was slightly more effective than methylphenidate (a medication used to treat ADHD) in improving behavior among hyperactive children. Although intriguing, the results of this study were not significant and no other studies have been able to confirm these findings. Therefore, supplementation with vitamin B6 is not considered standard treatment for ADHD. Rheumatoid Arthritis Low levels of vitamin B6 have been associated with rheumatoid arthritis. This may be due to low dietary intake of vitamin B6 and other important nutrients by people with this joint disorder. Eating a balanced diet, including a complete vitamin B complex, is a good idea for anyone with a chronic illness, such as rheumatoid arthritis. It is not known if taking extra vitamin B6 is of any use if you have arthritis. Sources All foods contain some vitamin B6; however, the following foods have the highest amounts: brewer's yeast, carrots, chicken, eggs, fish, meat, peas, spinach, sunflower seeds, walnuts, and wheat germ. Other sources include avocado, bananas, beans, blackstrap molasses, broccoli, brown rice and other whole grains, cabbage, cantaloupe, corn, dulse, plantains, potatoes, rice bran, soybeans, and tempeh. Herbs that contain vitamin B6 include alfalfa, catnip, and oat straw. Recommended dose Daily recommendations for dietary vitamin B6 are listed below. Pediatric
Nausea and vomiting during early pregnancy: studies on this topic have used 10 mg per day. The amount to use, however, should be determined together with your obstetrician. Therapeutic doses for some of the conditions discussed in the Uses section have ranged from 100 to as high as 1,800 milligrams per day. Using doses higher than 200 mg per day for long periods of time, however, may cause neurologic disorders. Precautions Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable healthcare provider. Vitamin B6 can cause neurological disorders, such as loss of sensation in legs and imbalance, when taken in high doses (200 mg or more per day) over a long period of time. Discontinuing high doses usually leads to a complete recovery within 6 months. There have been extremely rare reports of allergic skin reactions to high doses of vitamin B6 supplements. Possible Interactions If you are currently being treated with any of the following medications, you should not use vitamin B6 supplements without first talking to your healthcare provider. Antibiotics, Tetracycline Vitamin B6 should not be taken at the same time as the antibiotic tetracycline because it interferes with the absorption and effectiveness of this medication. Vitamin B6 either alone or in combination with other B vitamins should be taken at different times from tetracycline. (All vitamin B complex supplements act in this way and should therefore be taken at different times from tetracycline.) Antidepressant Medications, Tricyclic Taking vitamin B6 supplements may improve the effectiveness of certain tricyclic antidepressants such as nortriptyline, especially in elderly individuals. Other tricyclic antidepressants include desipramine and imipramine. On the other hand, another class of antidepressants called monoamine oxidase inhibitors (MAOIs) may reduce blood levels of vitamin B6. Examples of MAOIs include phenelzine and tranylcypromine. Antipsychotic Medications Preliminary evidence suggest that pyridoxine may prove useful in treating tardive dyskinesia, a common but frustrating side effect from medications used to treat schizophrenia. Tardive dyskinesia is marked by involuntary movements of the mouth and tongue. More research is needed to know if vitamin B6 can help prevent or treat this side effect. Tuberculosis Medications Anti-tuberculosis medications such as isoniazid (INH) and cycloserine (used for resistant forms of tuberculosis) reduce the levels of vitamin B6 in the blood. Birth control medications Birth control medications may reduce blood levels of vitamin B6. Chemotherapy Vitamin B6 may reduce certain side effects of 5-fluorouracil and doxorubicin, two agents used to treat cancer without reducing the effectiveness of the chemotherapy. Erythropoietin Erythropoietin therapy used for severe anemia may decrease vitamin B6 levels in red blood cells. Therefore, vitamin B6 supplementation may be necessary during erythropoietin therapy. Hydralazine Vitamin B6 decreases the effectiveness of hydralazine, a medication used to treat high blood pressure. Levodopa Vitamin B6 reduces the effectiveness of levodopa, a medication used to treat Parkinson's disease. Methotrexate People with rheumatoid arthritis taking this medication often have low levels of vitamin B6. Penicillamine Penicillamine, a medication used in the treatment of rheumatoid arthritis and Wilson's disease (excessive amounts of copper in the body that can lead to liver damage) may decrease levels of vitamin B6 in the body. Phenytoin Vitamin B6 reduces the effectiveness of phenytoin, a medication used to treat seizures. Theophylline Long-term treatment with theophylline for asthma may reduce blood levels of vitamin B6. Suggested Reading:
Vitamin B12 is needed to prevent anemia. It aids folic acid in regulating the formation of red blood cells, and helps in the utilization of iron. This vitamin is also required for proper digestion, absorption of foods, the synthesis of protein, and the metabolism of carbohydrates and fats. It aids in cell formation and cellular longevity. In addition, vitamin B12 prevents nerve damage, maintains fertility, and promotes normal growth and development by maintaining the fatty sheaths that cover and protect nerve endings. Vitamin B12 is linked to the production of acetylcholine, a neurotransmitter that assists memory and learning. Vitamin B12 supplementation has been shown to enhance sleep patterns, allowing for more restful and refreshing sleep. A vitamin B12 deficiency can be caused by malabsorption, which is most common in elderly people and in those with digestive disorders. Deficiency can cause abnormal gait, bone loss, chronic fatigue, constipation, depression, digestive disorders, dizziness, drowsiness, enlargement of the liver, eye disorders, hallucinations, headaches (including migraines), inflammation of the tongue, irritability, labored breathing, memory loss, moodiness, nervousness, neurological damage, palpitations, pernicious anemia, ringing in the ears, and spinal cord degeneration. Strict vegetarians must remember that they require vitamin B12 supplementation, as this vitamin is found almost exclusively in animal tissues. Although people adopting a strictly vegetarian diet may not see any signs of the deficiency for some time—the body can store up to five years' worth of vitamin B12—signs will eventually develop. Uses Pernicious Anemia The most important use of vitamin B12 is to treat the symptoms of pernicious anemia. These symptoms include weakness, pale skin, diarrhea, weight loss, fever, numbness or tingling sensation in the hands and feet, loss of balance, confusion, memory loss, and moodiness. Heart Disease Many studies indicate that patients with elevated levels of the amino acid homocysteine are roughly 1.7 times more likely to develop coronary artery disease and 2.5 times more likely to suffer from a stroke than those with normal levels. Homocysteine levels are strongly influenced by B complex vitamins, particularly vitamins B9, B6, and B12. The American Heart Association recommends that, for most people, an adequate amount of these important B vitamins be obtained from the diet, rather than taking extra supplements. Under certain circumstances, however, supplements may be necessary. Such circumstances include elevated homocysteine levels in someone who already has heart disease or who has a strong family history of heart disease that developed at a young age. Alzheimer's Disease Vitamin B9 (folate) and vitamin B12 are critical to the health of the nervous system and to a process that clears homocysteine from the blood. As stated earlier, homocysteine may contribute to the development of certain illnesses such as heart disease, depression, and Alzheimer's disease. Elevated levels of homocysteine and decreased levels of both folate and vitamin B12 have been found in people with Alzheimer's disease, but the benefits of supplementation for dementia are not yet known. Depression Studies suggest that vitamin B9 (folate) may be associated with depression more than any other nutrient. Between 15% and 38% of people with depression have low folate levels in their bodies and those with very low levels tend to be the most depressed. Low folate levels tend to lead to elevated homocysteine levels. Many healthcare providers recommend a B complex multivitamin that contains folate as well as vitamins B6 and B12 to improve symptoms. If the multivitamin with these B vitamins is not enough to bring elevated homocysteine levels down, the physician may then recommend higher amounts of folate along with vitamins B6 and B12. Again, these three nutrients work closely together to bring down high homocysteine levels, which may be related to the development of depression. Burns It is especially important for people who have sustained serious burns to obtain adequate amounts of nutrients in their daily diet. When skin is burned, a substantial percentage of micronutrients may be lost. This increases the risk for infection, slows the healing process, prolongs the hospital stay, and even increases the risk of death. Although it is unclear which micronutrients are most beneficial for people with burns, many studies suggest that a multivitamin including the B complex vitamins may aid in the recovery process. Osteoporosis Keeping bones healthy throughout life depends on getting sufficient amounts of specific vitamins and minerals, including phosphorous, magnesium, boron, manganese, copper, zinc, folate, and vitamins C, K, B6, and B12, and B6. In addition, some experts believe that high homocysteine levels may contribute to the development of osteoporosis. If this is the case, then there may prove to be a role for dietary or supplemental vitamins B9, B6, and B12. Cataracts Dietary and supplemental vitamin B complex is important for normal vision and prevention of cataracts (damage to the lens of the eye which can lead to cloudy vision). In fact, people with plenty of protein and vitamins A, B1, B2, and B3 (niacin) in their diet are less likely to develop cataracts. Plus, taking additional supplements of vitamins C, E, and B complex (particularly the B1, B2, B9 [folic acid], and B12 [cobalamin] in the complex ) may further protect the lens of your eyes from developing cataracts. Human Immunodeficiency Virus (HIV) Blood levels of vitamin B12 are often low in people with HIV. It is unclear, however, what role vitamin B12 supplements would play in treatment. If you have HIV, your levels of vitamin B12 should be followed over time and B12 injections may be considered if levels get too low, especially if you have symptoms of B12 deficiency. Breast Cancer Population based studies of postmenopausal women suggest that low vitamin B12 levels in the blood may be associated with an increased risk for breast cancer. It is not clear whether supplementation with vitamin B12 reduces the risk of this disease, however. Male Infertility Studies suggest that vitamin B12 supplements may improve sperm counts and sperm mobility. Further studies are needed to best understand how this can help men with a low sperm count or poor sperm quality. Sources The largest amounts of vitamin B12 are found in brewer's yeast, clams, eggs, herring, kidney, liver, mackerel, milk and dairy products, and seafood. Vitamin B12 is not found in many vegetables; it is available only from sea vegetables, such as dulse, kelp, kombu, and nori, and soybeans and soy products. It is also present in the herbs alfalfa, bladder-wrack, and hops. Recommended dose Daily recommendations for dietary vitamin B12 are listed below. Pediatric
Precautions Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable healthcare provider. Vitamin B12 is considered safe and non-toxic. Taking any one of the B complex vitamins by itself for a long period of time can result in an imbalance of other important B vitamins. For this reason, it is generally important to take a B complex vitamin with any single B vitamin. Possible Interactions If you are currently being treated with any of the following medications, you should not use vitamin B12 supplements without first talking to your healthcare provider. Antibiotics, Tetracycline Vitamin B12 should not be taken at the same time as the antibiotic tetracycline because it interferes with the absorption and effectiveness of this medication. Vitamin B12 either alone or in combination with other B vitamins should be taken at different times of the day from tetracycline. (All vitamin B complex supplements act in this way and should therefore be taken at different times from tetracycline.) In addition, long-term use of antibiotics can deplete vitamin B levels in the body, particularly B2, B9, B12, and vitamin H (biotin), which is considered part of the B complex. Anti-ulcer Medications The body's ability to absorb vitamin B12 is decreased when taking stomach acid-reducing medications such as omeprazole, lansoprazole, ranitidine, cimetidine, or antacids that are often used to treat gastroesophageal reflux, ulcers or related symptoms. This interference is most likely to occur as a result of prolonged use (more than one year) of these medications. Chemotherapy Medications Blood levels of vitamin B12 may be reduced when taking chemotherapy medications (particularly methotrexate) for cancer. Metformin for diabetes Blood levels of vitamin B12 may also be reduced when taking metformin for diabetes. Phenobarbital and Phenytoin Long-term treatment with either phenobarbital and phenytoin for seizure disorders may interfere with the body's ability to use vitamin B12. Taking vitamin B12 in sublingual tablets, which are dissolved under the tongue rather than swallowed, can be a good option for those who have difficulty absorbing this vitamin. Intrinsic factor is a protein produced in the gastrointestinal tract that is necessary for absorption of vitamin B12. People who lack intrinsic factor must use a sublingual form for absorption. Suggested Reading:
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