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Vitamin E

Common Name: Vitamin E
Synonyms: the alpha, beta, delta and gamma tocopherols and the alpha, beta, delta and gamma tocotrienols.

Overview:

Vitamin E is a fat soluble vitamin. In its natural state, vitamin E has two forms, tocopherol and tocotrienols. Vitamin E is a powerful antioxidant and is an essential (a nutrient required for normal body functioning and cannot be made by the body) nutrient in humans. Vitamin E works in fats and lipids while its counterpart vitamin C works against free radicals in water. Vitamin E helps to eliminate the free radicals that con contribute to the development of heart disease, cancer and many inflammatory conditions like arthritis, as well as the tissue damage caused by the toxins and pollutants present in the environment.

A vitamin E deficiency is often seen in conditions where the body is unable to properly breakdown fats, such as pancreatitis, cystic fibrosis, Crohn’s disease, celiac disease as well as gallbladder disease. The symptoms of a vitamin E deficiency include muscle weakness, loss of muscle mass, abnormal eye movements, impaired vision, and an unsteady gait. Severe vitamin deficiency can even lead to serial miscarriages as well as premature births.
All forms of vitamin E have antioxidant qualities. It has also been found to decrease the ability of platelets to clump, therefore preventing blood clots. It also also been shown to stabilize cell membranes, strengthens the immune system, protects the nervous system and may have antiviral properties.

Benefits

Studies have shown the many benefits of vitamin E.

  1. Vitamin E appears to inhibit platelets from sticking together and forming blood clots. Tests, in tissue culture, shows that vitamin E lessens the ability of platelets to stick together. Vitamin E has also been found to decrease the production of thrombin. Thrombin is what caused platelets to bind together to form a clot.
  2. A large number f studies that include in vitro (in the test tube) and animal studies as well as epidemiological (the study of the causes, distribution, and control of disease in populations) and intervention studies are showing the importance of vitamin E in preventing cardiovascular disease. Vitamin E has been shown to prevent the destruction of LDL (good cholesterol) in various studies. Other studies show that vitamin E acts on the ability of the blood to clot, platelet clumping and the relaxation of arterial walls. These all lead to reduction in cardiovascular risk.

In an animal study, rabbits with high lipid levels were supplemented with vitamin E. Those that received the supplement showed a decrease in the breakdown of LDL into HDL (bad cholesterol). Rabbits on high cholesterol diets that were supplemented with vitamin E showed normal arteries while those who did not receive the supplements did not. Animal studies have continued to show that vitamin E supplements can reduce the formation of atheromas (the accumulation of fat deposits) by 25 to 50%.

Again epidemiological studies have sown the connection with low-vitamin E levels and an increased risk of heart disease. In a large case-controlled study the results suggested that the higher the concentrations of vitamin E in the bodies fat stores the lower the risk of heart attack.

In the Nurses Health Study, 8700 nurses that were free of cardiovascular disease at the beginning of the study, a 34% reduction in the risk of coronary heart disease was seen in the women with the highest intake of vitamin E when compared to those with the lowest

  1. It has been noted that people who develop cancer have lower levels of vitamin E. In population based trials, diets rich in vitamin E have shown a reduced risk of colon cancer.. Laboratory studies have also shown that vitamin E inhibits the growth of cancer cells in vitro and in animal studies.
  2. People with photodermatitis (an allergic reaction to UV rays from the sun) showed less sensitivity to the sun when treated with vitamin E and C supplements as compared to no treatment.
  3. Vitamin E may be helpful in the treatment of Alzheimer’s disease. Fat soluble vitamins easily cross into the brain. Vitamin E’s antioxidant properties coupled with it ability to reduce plaque build up may help in improving the cognitive function of healthy individuals as well has those with dementia.
  4. The antioxidant properties of vitamin E may protect against cataract formation as well as ARMD (age related macular degeneratio

Dietary Sources

Wheat germ is the best source of vitamin E. It is also found in:

Soybean, Cottonseed and Canola Oils
Soybean, Cottonseed and Canola Oils
Kale, Turnips, Collards, and Mustard Greens
 Kale, Turnips, Collards, and Mustard Greens
Sweet Potatoes
Sweet Potatoes
Avocados
 Avocados
AsparagusAsparagus


Recommended Dosage:

The U.S. recommendations for daily intake of vitamin E are:

  1. Infants 0–6 months, 4 mg
    7–12 months,5 mg
  2. Children 1–3 years, 6 mg
    4–8 years, 7 mg
    9–13 years, 11 mg
  3. Males and females 14 years and older, 15 mg
  4. Pregnant women, 15 mg
  5. Nursing women, 19 mg

Vitamin E supplements should be taken along with selenium.
Doses of vitamin E over 1000mg can cause diarrhea, gas, nausea, heart palpitations and tendency to bleed easily.

Contra-indications

Vitamin E can inhibit the uptake of:

  1. Tricyclic antidepressants such as desimpramine uptake are inhibited by vitamin E supplements.
  2. antipsychotic medication chlorpromazine.
  3. Beta blocker for hypertension
  4. Chloroquine an antimaleria medication

Cholesterol lowering medications may decrease the absorption of vitamin E

Vitamin E has shown to be helpful:

  1. Preventing the toxicity and side effects from AZT a medication used to treats HIV and AIDS.
  2. Vitamin E may provide antioxidant benefits to women taking birth control pills or on hormone replacement therapy.
  3. Taken along with vitamin C counteracted the cholesterol raising effects of Tamoxifen

Vitamin E has been shown to be safe when taken with aspirin.

Vitamin E taken at the same time as warfarin may lead to abnormal bleeding.

Women who are pregnant or breastfeeding should consult a health care provider before starting any supplement.

WEB References

  1. http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/vit_0265.shtml
  2. http://en.wikipedia.org/wiki/Vitamin_E
  3. http://www.umm.edu/altmed/index.html

Printed Reference Material

  1. Anderson DK, Waters TR, Means ED. Pretreatment with alpha-tocopherol enhances neurologic recovery after experimental spinal cord compression injury. J Neurotrauma. 1998; 5:61-67.
  2. Baumann LS, Spencer J. The effects of topical vitamin E on the cosmetic appearance of scars. Dermatol Surg. 1999; 25:311-315.
  3. Bozbuga M, Izgi N, Canbolat A. The effects of chronic alpha-tocopherol administration on lipid peroxidation in an experimental model of acute spinal cord injury. Neurosurg Rev. 1998; 21:36-42.
  4. Brigelius-Flohe R, Traber MG. Vitamin E: function and metabolism. FASEB J. 1999; 13:1145-1155.
    Bursell S-E, King GL. Can protein kinase C inhibition and vitamin E prevent the development of diabetic vascular complications? Diabetes Res Clin Pract. 1999; 45:169-182.
  5. Burton GW, Traber MG, Acuff RV, et al. Human plasma and tissue alpha-tocopherol concentrations in response to supplementation with deuterated natural and synthetic vitamin E. Am J Clin Nutr. 1998; 67:669-684.
  6. Delcourt C, Cristol J-P, Tessier F, et al. Age-related macular degeneration and antioxidant status in the POLA study. Arch Opthalmol. 1999; 117:1384-1390.
  7. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium and Carotenoids. Washington, D.C.: National Academy Press; 2000.
  8. Dowd P, Zheng ZB. On the mechanism of the anticlotting action of vitamin E quinone. Proc Natl Acad Sci USA. 1995; 92:8171-8175.
  9. GISSI-Prevenzione Investigators. Dietary supplementation with n-3 polyunsaturated fatty acids and vitamin E after myocardial infarction: results of the GISSI-Prevenzioni trial. Lancet. 1999; 354:447-455.
  10. Gogu SR, Lertora JJL, George WJ, et al. Protection of zidovudine-induced toxicity against murine erythroid progenitor cells by vitamin E. Exp Hematol. 1999; 19:649-652.
  11. Grundman M. Vitamin E and Alzheimer's disease: the basis for additional clinical trials. Am J Clin Nutr. 2000; 71:630S-636S.
  12. Heinonen OP, Albanes D, Virtamo J, et al. Prostate cancer and supplementation with alpha-tocopherol and beta-carotene: incidence and mortality in a controlled trial. J Natl Cancer Inst. 1998; 90:440-446.
  13. Hendler SS, Sanchez R. Tocopherol-based antiviral agents and method of using same. United States Patent Number 5, 114, 957. 1992.
  14. Kayden HJ, Traber M. Absorption, lipoprotein transport and regulation of plasma concentrations of vitamin E in humans. J Lipid Res. 1993; 34:343-358.
  15. Knekt P, Reunanen A, Marniemi J, et al. Low vitamin E status is a potential risk factor for insulin-dependent diabetes mellitus. J Intern Med. 1999; 245:99-102.
  16. Lee I-K, Koya D, Ishi H, et al. Alpha-tocopherol prevents the hyperglycemia induced activation of diacylglycerol (DAG)-protein kinase C (PKC) pathway in vascular smooth muscle cell by an increase of DAG kinase activity. Diabetes Res Clin Pract. 1999; 45:189-190.
  17. Meydani SN, Meydani M, Blumberg JB, et al. Vitamin E supplementation and in vivo immune response in healthy elderly subjects. JAMA. 1997; 277:1380-1386.
  18. Paolisso G, Gambardella A, Giugliano D, et al. Chronic intake of pharmacological doses of vitamin E might be useful in the therapy of elderly patients with coronary heart disease. Am J Clin Nutr. 1995; 61:848-852.
  19. Pryor WA. Vitamin E and heart disease: basic science to clinical intervention trials. Free Rad Biol Med. 2000; 28:141-164.
  20. Rapola JM, Virtamo J, Ripatti S, et al. Effects of alpha-tocopherol and beta-carotene supplements on symptoms, progression, and prognosis of angina pectoris. Heart. 1998; 79:454-458.
  21. Rimm EB, Stampfer MJ, Ascherio A, et al. Vitamin E consumption and the risk of coronary heart disease in men. N Engl J Med. 1993; 328:1450-1456.
  22. Sano M, Ernesto C, Thomas RG, et al. A controlled trial of selegiline, alpha-tocopherol, or both as treatment for Alzheimer's disease. N Engl J Med. 1997; 336:1216-1222.
  23. Shoulson I. DATATOP: a decade of neuroprotective inquiry. Parkinson Study Group. Deprenyl and tocopherol antioxidative therapy of Parkinsonism. Ann Neurol. 1998; 44(3 Suppl 1): S160-S166.
  24. Stahl W, Heinrich U, Jungmann H, et al. Ca

Vitamin D

Common Name: Vitamin D
Synonyms: Calciferol, calcitriol, cholecalciferol (D3), ergocalciferol (D2)

Overview:

Vitamin D is a fat-soluble vitamin. Vitamin D comes in two forms ergocalciferol or vitamin D2 and cholecalciferol, vitamin D3. Vitamin D2 comes from food sources while vitamin D3 is manufactured in the skin when it is exposed to sunlight. Until vitamin D is metabolized in the liver to 25-hydroxyvitamin D3. This form of vitamin D is also inactive until metabolized in the kidneys to produce the final vitamin D which is a pro hormone. This pro-hormone has no hormonal activity of its own. It is must be converted into the molecule that does, 1 alpha, 25-dihydroxyvitamin D . This hormone plays vital role in the: absorption of calcium and phosphorous from the intestines, in mobilizing calcium from bone, and the reabsorption of calcium by the kidneys. Because of its role as a hormone, Vitamin D is also responsible for the growth of the parathyroid gland as well as the production of the parathyroid hormone. When vitamin D levels decrease, the parathyroid hormone level increases. This leads to the reabsorption of bone. Vitamin D has also shown the ability to enhance the functioning of the immune system, helps regulate insulin secretion and plays an important role in female reproduction.
Because vitamin D is not found in many food sources, it has been added to milk and cereal to help prevent a deficiency. Vitamin D supplements are very important when sun exposure is limited. Vitamin D deficiencies are very common in people who do not drink milk or receive little sun exposure. It is very common in:

  • The elderly, who tend to spend more time indoors
  • Those living in northern latitudes. In fact vitamin D supplements are recommended for those who live north of the Mason Dixon line in the United States.
  • People who were protective clothing or sun block in the summer time.
  • People with liver problems or alcoholics
  • Those with malabsorption syndromes such as Crohn’s’ disease, cystic fibrosis, and celiac disease.
  • The use of certain medications that interfere with vitamin D absorption or metabolism.

The lack of vitamin D affects bone growth and development. A disease, in children, called rickets is caused by a vitamin D deficiency. Rickets results in demineralization that results in a softening and weakening of the bone. This disease was quite common in children and often resulted in severely bowed legs. In countries like the United States that fortify milk with vitamin D, rickets is rarely seen. In adults this softening and weakening of the bone is called osteomalcia and will eventually lead to reabsorption of the calcium in the bone and results in osteoporosis. Vitamin D is also involved in maintaining the immune system, normal muscle contractions, nerve and blood formation and is involved in cancer prevention.


Benefits

Vitamin D has been studied extensively. The research is in and it has shown how vitamin D improves our health.

  • Several studies have found a strong association between low vitamin D levels and the incidence of osteoarthritis and bone fractures. Low levels of vitamin D have also been associated with the progression of arthritis of the knee in the participants in the Farmington study. This deterioration of the knee was documented by x-rays at various intervals in the 10 year period of the study. As the vitamin D level decreased the progression of the arthritis increased. Low vitamin D levels were associated with the loss of cartilage in the knee.

A more recent study found that a severely low level of vitamin D in post menopausal women was closely linked with fractures of the hip. The vitamin D levels were so small as to be hard to detect. Low vitamin D levels lead to an increase in the parathyroid hormone and demineralization of bone.

Still another study has sown that vitamin D may counteract the effects of corticosteroids on bone reabsorption. This is because it increases the absorption of calcium from the small intestines while at the same time inhibiting the production of the parathyroid hormone.

  • Vitamin D also enhances the function of the immune system. In its active form, vitamin D enhances the functioning of monocytes (a type of white blood cell that helps destroy bacteria that enter the body). Before the advent of drugs to treat tuberculosis, cod liver oil and sunshine were used successfully to treat tuberculosis. With the new antibiotic resistant tuberculosis emerging, these old time treatments are regaining popularity.
  • Vitamin D has been found to inhibit the proliferation of cells in several malignant cell lines including prostate cancer. The active from of Vitamin D suppresses in vitro (in the test tube) grown of human cancers such as colon cancer and malignant melanoma. The anti cancer activity of vitamin D is not very well understood and much research into this process in underway.
  • The active form of vitamin D, 1,25-dihydrovitamin D has been found to be an effective treatment for psoriasis when used in cream form. Psoriasis is a skin disorder that involves abnormal skin growth and the development of large areas of thickened, reddish skin covered with scales.
  • Vitamin D also plays a role in the treatment of SAD (seasonal affective disorder) that affects many people in northern latitudes during the winter when sunshine is at a minimum. How it works to help alleviate the depression that accompanies this disorder is not well understood.
  • Researchers have found a connection between MS (multiple sclerosis) lesions and season. These researchers surmise that adequate vitamin D levels contribute to the lessening of MS lesion activity. These researchers indicate that this impressive correlation need proper clinical trials to demonstrate vitamin D’s role in reducing central nervous system lesions and the slowing of the progression of MS.
  • Vitamin D supplementation is proving helpful in those taking anti seizure medication and corticosteroids. Both of these medications are known to reduce bone mass.

Dietary Sources

The sun is the best source of vitamin D. although both milk and cereals have been fortified with vitamin D, the few natural sources of vitamin D are:

Salmon
 Salmon
Sardines
 Sardines
Eel
 Eel
Mackerel, Tuna and Herring
Mackerel, Tuna and Herring
Cod Liver Oil
 Cod Liver Oil
Eggs
 Eggs
Milk Fortified with Vitamin D Milk Fortified with Vitamin D


Recommended Dosage:

The official U.S. and Canadian recommendations for daily intake of vitamin D are as follows:

  • Infants 0–12 months, 200 IU (5 mcg)
  • Males and females 1–50 years, 200 IU (5 mcg)
    51–70 years, 400 IU (10 mcg)
    71 years and older, 600 IU (15 mcg)
  • Pregnant women, 200 IU (5 mcg)
  • Nursing women, 200 IU (5 mcg)

When taken in at the recommended doses Vitamin D is considered safe. Since vitamin D is a fat soluble vitamin it can be stored in the body. Vitamin D toxicity can develop when it is taken in large amounts. Below is a list of the safe upper limits for vitamin D daily intake.

  • Infants 0–12 months, 1,000 IU (25 mcg)
  • Males and females 1 year and older, 2,000 IU (50 mcg)
  • Pregnant and nursing women, 2,000 IU (50 mcg)

Contra-indications

  • People with sarcoidosis (a condition where small lumps of tissue appear in any organ of the body including the skin) or hyperparathyroidism should never take vitamin D without first consulting a physician.
  • Chronic doses that exceed 95mg or 3800I/U can lead to much calcium in the blood. Some of the symptoms of early hypercalcemia are nausea, vomiting, weakness, headaches, dry mouth, constipation, muscle and bone pain. Late symptoms of this condition are anorexia, weight loss, conjunctivitis, pancreatitis, sensitivity to light, and runny nose, the depositing of calcium in the major organs of the body, hypertension and cardiac arrhythmias.
  • High doses of vitamin D to treat medical conditions should be undertaken under the supervision of a qualified healthcare practioner.
  • Women who are pregnant or breastfeeding should consult a health care provider before taking a vitamin D supplement.

Drug interactions

  • The following drugs can interfere with the absorption of vitamin D, Cholestyramine and Colestipol (cholesterol lowering medications), mineral oil and orlistat (a weight loss medication).
  • Olestra, a fat substitute may interfere with the absorption of Vitamin D and the other fat soluble vitamins A, E, and K. Olestra has been fortified with these vitamins to make up for the decrease in the body’s ability to absorb these vitamins.
  • Phenobarbital and Phenytoin may lower blood levels of vitamin D by inhibiting the metabolism of vitamin D by the liver.

References

  1. http://healthlibrary.epnet.com/GetContent.aspx?token=e0498803-7f62-4563-8d47-5fe33da65dd4&chunkiid=21657
  2. http://lpi.oregonstate.edu/infocenter/vitamins/vitaminD/
  3. http://www.umm.edu/altmed/ConsSupplements/VitaminDcs.html
  4. http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/vit_0265.shtml

Printed Reference Material

  1. American Academy of Sciences. Dietary Reference Intakes: Calcium Phosphorus, Magnesium, Vitamin D, and Fluoride. National Academy Press; 1997.
  2. Bikle DD, Halloran BP, Harris ST, Portale AA. Progestin antagonism of estrogen stimulated 1,25-dihydroxyvitamin D levels. J Clin Endocrinol Metab. 1992;75(2):519-523.
  3. Blank RD, Bockman RS. A review of clinical trials of therapies for osteoporosis using fracture as an end point. J Clin Densitom. 1999;2(4):435-452.
  4. Braun J, Sieper J. [Glucocorticoid-induced osteoporosis] Orthopade. 2001;30(7):444-450. German.
  5. Brawley OW, Parnes H. Prostate cancer prevention trials in the USA. Eur J Cancer. 2000;36(10):1312-1315.
  6. Brenner RV, Shabahang M, Schumaker LM, et al. The antiproliferation effect of vitamin D analogs on MCF-7 human breast cancer cells. Cancer Lett. 1995;92:77–82.
  7. Chan JM, Giovannucci E, Andresson SO, Yuen J, Adami HO, Wolk A. Dairy products, calcium, phosphorous, vitamin D, and risk of prostate cancer (Sweden). Cancer Causes Control. 1998;9(6):559-566.
  8. Clemens TL, Adams JS, Henderson SL, Holick MF. Increased skin pigment reduces the capacity of skin to synthesise vitamin D3. Lancet. 1982;1(8263):74-76.
  9. Dawson-Hughes B, Harris SS, Dallal GE. Plasma calcidiol, season, and serum parathyroid hormone concentrations in healthy elderly men and women. Am J Clin Nutr. 1997;65:67–71.
  10. Dawson-Hughes B, Harris SS, Krall EA, et al. Effect of calcium and vitamin D supplementation on bone density in men and women 65 years of age and older. N Engl J Med. 1997;337:670–676.
  11. Fox J. Verapamil induces PTH resistance but increases duodenal calcium absorption in rats. Am J Physiol. 1988;255(5):E702-707.
  12. Gallagher JC, Fowler SE, Detter JR, Sherman SS. Combination treatment with estrogen and calcitriol in the prevention of age-related bone loss. J Clin Endocrin Metabol. 2001;86(8):3618-3628.
  13. Garland CF, Garland FC, Gorham ED. Calcium and vitamin D: their potential roles in colon and breast cancer prevention. Ann NY Acad Sci. 1999;889:107-119.
  14. Kato S. The function of vitamin D receptor in vitamin D action. J Biochem. 2000; 127:717-722.
  15. Kensler TW, Dolan PM, Grange SJ, et al. Conceptually new deltanoids (vitamin D analogues) inhibit multistage skin tumorigenesis. Carcinogenesis. 2000; 21:1341-1345.
  16. Kreiter SR, Schwartz RP, Kirkman HN Jr., et al. Nutritional rickets in African American breast-fed infants. J Pediatr. 2000; 137:153-157.
  17. Lal H, Pandey R, Aggarwal SK. Vitamin D: non-skeletal actions and effects on growth. Nutr Res. 1999; 19:1683-1718.
  18. Landsdowne ATG, Provost SC. Vitamin D3 enhances mood in healthy subjects during winter. Psychopharmacol. 1998; 135:319-323.
  19. Lane NE, Gore L, Cummings SR, et al. Serum vitamin D levels and incident changes of radiographic osteoarthritis. Arthritis Rheum. 1999; 42:854-860.
  20. LeBoff MS, Kohlmeier L, Hurwitz S, et al. Occult vitamin D deficiency in postmenopausal US women with acute hip fracture. JAMA. 1999; 281:1505-1511.
  21. Lips P, Graafmans WC, Ooms ME, et al. Vitamin D supplementation and fracture incidence in elderly persons. A randomized, placebo-controlled clinical trial. Ann Intern Med. 1996; 124:400-406.
  22. Lowe KE, Norman AW. Vitamin D and psoriasis. Nutr Rev 1992; 50:138-142.
  23. Malloy PJ, Feldman D. Vitamin D resistance. Am J Med. 1999; 106:355-370.
  24. Malloy PJ, Pike JW, Feldman D. The vitamin D receptor and the syndrome of hereditary 1, 25-dihydroxyvitamin D-resistant rickets. Endocrine Reviews. 1999; 20:156-188.
  25. Manolagas SC, Provvedini DM, Tsoukas CD. Interactions of 1, 25-dihydroxyvitamin D3 and the immune system. Mol Cell Endocrinol. 1985; 43:113-122.
  26. Mantell DJ, Owens PE, Bundred NJ, et al. 1alpha, 25-Dihydroxyvitamin D3 inhibits angiogenesis in vitro and in vivo. Circ Res. 2000; 87:214-220.
  27. McAlindon TE, Felson DT, Zhang Y, et al. Relation of dietary intake and serum levels of vitamin D to progression of osteoarthritis of the knee among participants in the Framingham study. Ann Int Med. 1996; 125:353-359.
  28. Mukhopadhyay S, Singh M, Chatterjee M. Vitamin D3 as a modulator of cellular antioxidant defense in murine lymphoma. Nutr Res. 2000; 20:91-102.
  29. O'Brien KO. Combined calcium and vitamin D supplementation reduces bone loss and fracture incidence in older men and women. Nutr Rev. 1998; 56(5 Pt 1):148-150.
  30. Prabhala A, Garg R, Dandona P. Severe myopathy associated with vitamin D deficiency in Western New York. Arch Intern Med. 2000
  31. Schlagheck TG, Riccardi KA, Zorich NL, Torri SA, Dugan LD, Peters JC. Olestra dose response on fat-soluble and water-soluble nutrients in humans. J Nutr. 1997;127(8 Suppl):1646S-1665S.
  32. Self TH, Chrisman CR, Baciewicz AM, Bronze MS. Isoniazid drug and food interactions. Am J Med Sci. 1999;317(5):304-311.
  33. Semba RD, Garrett E, Johnson BA, Guralnik JM, Fried LP. Vitamin D deficiency among older women with and without disability. Amer J Clin Nutr. 2000;72:1529-1534.
  34. Sowers MF, Lachance L. Vitamins and arthritis: The roles of vitamins A, C, D, and E. Rheum Dis Clin North Am. 1999;25(2):315-331.
  35. Staberg B, OxholmA, Klemp P, Christiansen C. Abnormal vitamin D metabolism in patients with psoriasis. Acta Derm Venereol. 1987;67(1):65-68.
  36. Thomas MK., Lloyd-Jones DM, Thadhani RI, et al. Hypovitaminosis D in medical inpatients. N Engl J Med. 1998;338:777–783.
  37. Thornquist MD, Kristal AR, Patterson RE, et al. Olestra consumption does not predict serum concentrations of carotenoids and fat-soluble vitamins in free-living humans: early results from the sentinel site of the olestra post-marketing surveillance study. J Nutr. 2000;130(7):1711-1718.
  38. Valmadrid C, Voorhees C, Litt B, Schneyer CR. Practice patterns of neurologists regarding bone and mineral effects of antiepileptic drug therapy. Arch Neurol. 2001;58(9):1369-1374.
  39. Watson KE, Abrolat ML, Malone LL, et al. Active serum vitamin D levels are inversely correlated with coronary calcification. Circulation. 1997;96(6):1755-1760.
  40. Wilkinson RJ, Llewelyn M, Toossi Z, et al. Influence of vitamin D deficiency and vitamin D receptor polymorphisms on tuberculosis among Gujarati Asians in west London: a case-control study. Lancet. 2000;355(9204):618-621.
  41. Wortsman J, Matsuoka LY, Chen TC, Lu Z, Holick MF. Decreased bioavailability of vitamin D in obesity. Am J Clin Nutr. 2000;72(3):690-693.

Vitamin C

Common Name: Vitamin C
Synonyms: Ascorbic acid, ascorbate

Overview:

The main function of vitamin C, a water soluble vitamin, is the growth and repair of tissues all over the body. Although most animals can make vitamin C from its raw materials, humans can not. The vitamin C our bodies need must come from the food we eat. As vitamin C is not stored in the body, to keep health, it must be eaten every day. Vitamin C helps the body manufacture collagen, a key protein in all connective tissue, cartilage and tendons of the body. It is also important in the body’s ability to heal.

Humans can not survive without vitamin C. A severe deficiency of vitamin C can affect every system in the body. A severe vitamin C efficiency or scurvy was a common ailment from ancient times until the early 19th century. This was because fresh fruits and vegetables were not readily available throughout the year. Sailors, who were often at sea for months or years at a time, were especially susceptible to scurvy. In the late 1700’s, it was discovered that citrus fruit could prevent the development of this debilitating disease. The symptoms that accompany scurvy are: wounds that refuse to heal, inflamed and bleeding gums, weakened tooth enamel, fatigue and malaise, swollen and painful joints, scaly, dry skin, anemia, muscle weakness, frequent infections, diarrhea, pulmonary and kidney problems and eventually coma and death.

Vitamin C is involved in the manufacturing and repair of all the body’s connective tissue components, elastin, fibronectin, the matrix of the bones as well as cellular procollegen secretion. Vitamin C is aids in the absorption, transport and storage of iron and is involved in the synthesis of corticosteroids, aldosterones. It is also involved in the conversion of cholesterol into bile salts. These are not the only roles of vitamin C. Vitamin C may be the most important water-soluble antioxidant in the body. Vitamin C is thought to play a role in preventing certain chronic degenerative disorders such as coronary artery disease and cancer. It also plays a role in: preventing atherosclerosis, helping to lower blood pressure, strengthening the immune system, protecting the eye from UV light damage as well as possible antiviral and anti-inflammatory roles.


Benefits

The benefits of vitamin C supplements have been a hotly debated topic for decades. There has been extensive investigation into what the role of vitamin C is in disease prevention and health maintained. What has been found out is:

  • Vitamin C’s antioxidant effects have been well established. Vitamin C has been in several studies of small groups of people suggested that 2000mg of vitamin C (3 glasses of orange juice) helped to decrease total cholesterol and LDL (the bad cholesterol) cholesterol levels as well as the levels of triglycerides. At the same time vitamin C was lowering cholesterol and triglycerides, it was raising HDL (the good cholesterol).
  • Many studies of vitamin C have shown that vitamin C supplementation has positive effects in maintaining cardiovascular health.

The studies in Finland were especially dramatic. The Finnish men suffer from a very high mortality rate from coronary artery disease. Finnish men also have low levels of vitamin C. These studies found that the more vitamin C deficient the test subject was the greater the risk of suffering a fatal heart attack.

Platelet clumping (often called platelet aggregation) plays a significant role in atherosclerosis. In two studies where patients received 2,000mg to 3000mg of vitamin C daily the clumping of platelets was reduced. Studies that used doses of 250mg did not show the same effect.

  • Epidemiological studies (the study of the causes, distribution, and control of disease in populations) have repeatedly shown that low intake of vitamin C is closely linked with hypertension. A recent double-blind, placebo-controlled study showed that the group who received 500mg of vitamin C for 30 days showed a 13mm of Hg drop in systolic blood pressure when compared to those who received no vitamin C. Population based studies have linked high blood pressure with the damage caused by free radicals

Many other studies have shown that the oral administration or intra-arterial infusion of from 1,000 to 2000mg of vitamin C exerted a positive effect on the vasodilatation (the ability of the arteries to expand allowing increased circulation to vital areas of the body such as the heart) in patients who suffered from coronary artery disease. These positive effects were especially noted in those who smoked or suffered from type 1 and type 2 diabetes.

In a report from the First National Health and Nutrition Exam, a strong link was seen between vitamin C intake and death. A review of this study’s findings showed that as the vitamin C intake increased the mortality rate decreased. Among men with the highest vitamin C intake the lower the SMR (standardized mortality ratio) was. In men with the highest vitamin C intake this was 0.65 for all causes of death, 0.78 for cancers and .58 for cardiovascular disease. In women this inverse relationship was also seen but it was not as dramatic, 0.90 for all causes, 0.86 for cancers and 0.75 for cardiovascular disease.

  • Vitamin C’s ability to inhibit the breakdown of cellular DNA appears to account for its ability to protect against various forms of cancer. Numerous epidemiological and case controlled studies show a consistent relationship between high vitamin C intake and the lower incidence of cancer, particularly colo-rectal, stomach, lung, breast, esophageal, oral, and larynx-pharynx cancers.

In a review of 75 of these studies, 54 found that high vitamin C intake correlated with a reduced risk of developing cancer. In vitro (in the test tube) and animal studies, it has been shown that vitamin C reduces the toxicity of standard cancer therapies while at the same time increasing their effectiveness. Other researchers have shown that not only does vitamin C protect normal cells from the toxic effects of cancer therapies but it helps in the destruction of the cancer cells as well.

Many population studies have shown a strong connection between vitamin C intake and the development of cancer. A 29% reduction in the development of all types of cancer was seen in men taking 113mg of vitamin C daily. This was compared with those who were taking less. Another study found that in men who were taking over 300mg of vitamin C there was an associated 21% reduction in the risk of developing cancer when compared to those taking less than 49mg.

  • Studies have indicated that vitamin C enhances the ability of the immune system to fight of infections and maintain individual health. In vitro and animal studies have shown that vitamin C can change the numbers of lymphocytes and phagocytes (white blood cells that fight of infections) as well as control the number of natural killer cells and antibodies. Placebo-controlled studies have consistently shown that supplements of vitamin C in doses greater than 1000mg or more daily help to combat not only the symptoms of the common cold but

shortened the duration as well. The best results were seen in studies were the vitamin C supplementation was 200mg or greater. Studies have also shown that vitamin C is beneficial in other respiratory disease such as pneumonia and bronchitis. In three controlled studies the incident of these respiratory infections were greatly reduced when vitamin C was used as a supplement.

  • In case-controlled studies, high vitamin C intake was strongly linked to a reduction of cataract development. A 70% reduction in the risk of developing cataracts was seen when vitamin C was taken at a dose of 300mg or more per day. Another study showed a 75% reduction when 490mg or more was taken on a daily basis. It is believed that Vitamin C slows the clumping of proteins in the lens that causes the gradual clouding of the lens seen in cataract development. This has been demonstrated in animal and human lens. One study of women who took vitamin C for 10 years showed a major reduction in the development of cataracts as compared to those who did not supplement with vitamin C.
  • The level of vitamin C has been found to be inversely proportion to the incidence of gallbladder disease in women.
  • There is growing evidence that vitamin C that vitamin C can inhibit the growth of the bacteria Helicobacter pylori in both in vitro and animal studies. Helicobacter pylori are the bacteria that are responsible for the development of stomach ulcers. Stomach ulcers can turn into cancer of the stomach. In vitro studies showed that high concentrations of vitamin C inhibited the growth of Helicobacter pylori by 90%. This inhibition in the growth of these bacteria was confirmed in animal studies using high oral doses of vitamin C.
  • Vitamin C supplementation has also been shown to reduce the risk of RSD. RSD is a set of symptoms that occasionally develops in the legs or arms after fractures and other injuries. It involves persistent pain, changes in skin temperature, redness, swelling, and difficulty in movement. Its cause is unknown, and it has proven difficult, if not impossible, to treat. RSD causes significant suffering and disability. In this double blind, placebo-controlled study patients who suffered wrist fractures were given 500mg of vitamin C daily for 50 days. These patients were followed for a year. The incidence of RSD was greatly reduced in those who received the vitamin C supplements.
  • Vitamin C has been found to protect endothelial cells and reduce the capillary permeability seen in burn patients. This capillary permeability results in a tremendous loss of fluids seen in burn patients. This same cell protective mechanism of vitamin C is also seen in its ability to speed wound healing and to protect against gum disease.

Dietary Sources

Although citrus fruit is the most popular way of getting vitamin C, some vegetables actually have higher vitamin C content. Red chili peppers, sweet peppers, kale, parsley, collard and turnip greens contain large amounts of vitamin C. So are broccoli, Brussels sprouts, watercress, cauliflower, cabbage and strawberries. As vitamin C is partially destroyed by heat, fresh fruits and vegetables contain more vitamin C than cooked ones do.

Citrus Fruits
 Citrus Fruits
Chili Peppers
 Chili Peppers
Sweet Peppers
 Sweet Peppers
Cabbage
 Cabbage
Collard, Turnip Greens and Kale
 Collard, Turnip Greens and Kale
Parsley
 Parsley
Pineapple
 Pineapple
Tomatoes
 Tomatoes
Potatoes
 Potatoes
Winter Squash
 Winter Squash
Strawberries
 Strawberries
Blueberries
 Blueberries
CranberriesCranberries


Recommended Dosage:

Daily intake of dietary vitamin C (according to the U.S. RDA), are listed below.

Pediatric

  • Neonates 1 to 6 months: 30 mg
  • Infants 6 to 12 months: 35 mg
  • Children 1 to 3 years: 40 mg
  • Children 4 to 6 years: 45 mg
  • Children 7 to 10 years: 45 mg
  • Children 11 to 14 years: 50 mg
  • Adolescent girls 15 to18 years: 65 mg
  • Adolescent boys 15 to18 years: 75 mg

Adult

  • Men over 18 years: 90 mg
  • Women over 18 years: 75 mg
  • Breastfeeding women: first 6 months: 95 mg
  • Breastfeeding women: second 6 months: 90 mg

The U.S. government has issued recommendations regarding "tolerable upper intake levels" (ULs) for vitamin C. The UL can be thought of as the highest daily intake over a prolonged time known to pose no risks to most members of a healthy population. The ULs for vitamin C are as follows:

  • Children 1–3 years, 400 mg
    4–8 years, 650 mg
    9–13 years, 1,200 mg
  • Males and females 14–18 years, 1,800 mg
    19 years and older, 2,000 mg
  • Pregnant women 2000 mg (1,800 mg if18 years old or younger)
  • Nursing women 2000 mg (1,800 mg if18 years old or younger)

Although scurvy is rare in the United States, subtle vitamin C deficiency is very common. One study estimates that 40% of Americans do not get enough vitamin c in their diets.

Although many health groups encourage the use of huge doses of vitamin C as much as 20,000 to 30,000 mg daily, no studies to date have shown that these mega doses over any greater health. What researchers have found out that the more vitamin C ingested over 200mg daily, the vitamin C excreted by the kidneys matches the amount over the 200mg taken in. What this means is that no matter how much vitamin C is taken in, the level of vitamin C in the blood does not increase over this 200mg level. These studies, however did not measure the amount of vitamin C in the tissues nor the difference in taking these doses several times a day rather than just once.

SMOKING CIGARETTES SIGNIFICANTLY REDUCES THE LEVELS OF VITAMIN C IN THE CODY. SMOKERS SHOULD INCREASE THEIR VITAMIN C INTAKE BY 35mg IN ALL AGE GROUPS.

Vitamin C increases the absorption of dietary iron

Contra-indications

  • Vitamin C is often made commercially from corn. Those who suffer from allergies to corn or corn products should check their source of vitamin C. Some people are allergic to rose hips, another source of vitamin C. Again, those with an allergy to rose hips should check their source of vitamin C.
  • In healthy adults oral doses up to 3000mg daily are well tolerated. When atking oral doses over 3,000mg a day the only adverse side effects are gastrointestinal such as nausea, abdominal cramps and diarrhea.
  • In people with a history of kidney stones or who are in kidney failure should restrict their intake of vitamin C to 100mg a day.
  • People who suffer from a genetic condition known as glucose-6-phosphate dehydrogenase deficiency, hemochromatosis (a condition that causes a toxic build up of iron in the tissue) or a history of intestinal surgery should also avoid high doses of vitamin C.
  • Women who are pregnant or breastfeeding should consult a health care provider before supplementing with large doses of vitamin C.

Drug interactions

If you are taking any of the following medications or having any blood tests done, please consult a qualified healthcare practioner before starting a Vitamin C regime.

  • Aluminum containing antacids: when large doses of vitamin c are taken at the same time as aluminum containing antacids, an increase in the excretion of aluminum in the urine. This suggests that vitamin C increases the absorption of aluminum.
  • Aspirin: the absorption of vitamin C is inhibited by high doses of aspirin.
  • Chemotherapeutic agents: Vitamin C may strengthen the anticancer activity of drugs used in the treatment of cancer such as cisplatin, doxorubicin and paclitaxel. This is based on in vitro and animal studies.
  • Vitamin C/flavonoid combinations: Preparations that also contain grapefruit flavonoids may interact with some medications. Drugs that may be affected include the calcium channel blocker felodipine as well as carbamazepine, cyclosporines. Lovastatin, simvastation, saquinavir and nisoldipine. A qualified healthcare practioner should be consulted before using any grapefruit product.
  • Copper: It has been documented that high doses of vitamin C may affect the copper levels in men.
  • Flavonoids: Vitamin C and flavonoids seem to strengthen the ability of both substances to do their jobs.
  • Iron: Vitamin C increases the absorption of iron. In those with high iron stores this could lead to a potentially toxic iron overload. Those with hemochromatosis, sideroblastic anemia, sickle cell anemia, thalassemia and G6PD deficiency.
  • Large doses of vitamin C may interfere with the following laboratory tests:
    • Bilirubin assay were it can cause falsely elevated bilirubin levels.
    • Creatinine levels. Large doses of vitamin C can cause falsely elevated urine and serum creatinine levels.
    • Glucose levels. Large doses of vitamin C can cause falsely elevated glucose levels when using clinitest and falsely lowered glucose levels when using clinistix and Tes-tape.
    • Stool occult blood test. Doses of vitamin C larger than 1000mg a day can lead to a false negative test for occult blood in the stool
  • Acetaminophen: Vitamin C decreases the amount of acetaminophen (tylynol). Acetaminophen can become toxic at high levels. A healthcare practioner should be consulted before starting a vitamin C regime when acetaminophen is taken on a regular basis.
  • Vitamin C may intensify the effects of furosemide a loop diuretic
  • Beta channel blockers: vitamin C decreases the absorption of propranolol used in the treatment of high blood pressure. If taking both vitamin C and a beta-blocker it is best to take them at different times.
  • Cyclosporine has been shown to decrease the blood levels of vitamin C.
  • Nitroglycerine and other nitrate medications: Taking vitamin C when on nitrate medications for heart disease decreases the build up of these drugs in the body and helping to prevent the occurrence of nitrate tolerance.
  • Tetracycline: Studies have shown that taking vitamin C with tetracycline increases the level of this antibiotic in the blood.
  • There have been no reports of vitamin C overdoses in the literature

Web References

  1. http://lpi.oregonstate.edu/infocenter/vitamins/vitaminC/
  2. http://www.umm.edu/altmed/ConsSupplements/VitaminCAscorbicAcidcs.html
  3. http://healthlibrary.epnet.com/GetContent.aspx?token=e0498803-7f62-4563-8d47-5fe33da65dd4&chunkiid=21522
  4. http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/vit_0264.shtml

Printed Reference Material

  1. Blanchard J, Tozer TN, Rowland M. Pharmacokinetic perspective on megadoses of ascorbic acid. Am J Clin Nutr. 1997;66:1165–1171.
  2. Briggs M, Briggs M. Vitamin C requirements and oral contraceptives [letter]. Nature. 1972;238:277.
  3. Coffey G, Wilson SW. Letter: Ascorbic acid deficiency and aspirin-induced haematemesis. Br Med J. 1975;1:208.
  4. Das N, Nebioglu S. Vitamin C aspirin interactions in laboratory animals. J Clin Pharm Ther. 1992;17:343–346.
  5. Gandini S, Merzenich H, Robertson C, Boyle P. Meta-analysis of studies on breast cancer risk and diet: the role of fruit and vegetable consumption and the intake of associated micronutrients. Eur J Cancer. 2000;36:636-646.
  6. Giuliano AR, Gapstur S. Can cervical dysplasia and cancer be prevented with nutrients? Nutr Rev. 1988;56(1):9-16.
  7. Gokce N, Keaney JF, Frei B, et al. Long-term ascorbic acid administration reverses endothelial vasomotor dysfunction in patients with coronary artery disease. Circulation. 1999;99:3234-3240.
  8. Gonzalez J, Valdivieso A, Calvo R, Rodriguez-Sasiain J, et al. Influence of vitamin C on the absorption and first pass metabolism of propranolol. Eur J Clin Pharmacol. 1995;48:295-297.
  9. Gorton HC, Jarvis K. The effectiveness of vitamin C in preventing and relieving the symptoms of virus-induced respiratory infections. J Manipulative Physiol Ther. 1999;22(8):530-533.
  10. Harris JE. Interaction of dietary factors with oral anticoagulants: review and applications. J Am Diet Assoc. 1995;95(5):580-584.
  11. Head KA. Natural therapies for ocular disorders, part two: cataracts and glaucoma. Altern Med Rev. 2001;6(2):141-66.
  12. Hemila H. Does vitamin C alleviate symptoms of the common cold? A review of current evidence. Scand J Infect Dis. 1994;26:1–6.
  13. Hemila H. Vitamin C intake and susceptibility to the common cold. Br J Nutr. 1997;77:59-72.
  14. Hemilia H, Douglas RM. Vitamin C and acute respiratory infections. Int J Tuberc Lung Dis. 1999;3(9):756-761.
  15. Hemilia H. Vitamin C intake and susceptibility to the common cold. Br J Nutr. 1997;77(1):59-72.
  16. Houston JB, Levy G. Drug biotransformation interactions in man VI: acetaminophen and ascorbic acid. J Pharm Sci. 1976;65(8):1218-1221.
  17. Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Of Sciences. 2002. Accessed March 4, 2002 at www.iom.edu.
  18. Jacques PF. The potential preventive effects of vitamins for cataract and age-related macular degeneration. Int J Vitam Nutr Res. 1999;69(3):198-205.
  19. Johnston CS, Martin LJ, Cai X. Antihistamine effect of supplemental ascorbic acid and neutrophil chemotaxis. J Am Coll Nutr. 1992;11:172-176.
  20. Johnston CS. Recommendations for vitamin C intake. JAMA. 1999;282(22):2118-2119.
  21. Kaur B, Rowe BH, Ram FS. Vitamin C supplementation for asthma (Cochrane Rview). Cochrane Databse Syst Rev. 2001;4:CD000993.
  22. Kitiyakara C, Wilcox C. Antioxidants for hypertension. Curr Opin Nephrol Hyperten. 1998;7:S31-S38.
  23. Kune GA, Bannerman S, Field B, et al. Diet, alcohol, smoking, serum beta-carotene, and vitamin A in male nonmelanocytic skin cancer patients and controls. Nutr Cancer. 1992;18:237-244.
  24. Kurowska EM, Spence JD, Jordan J, Wetmore S, Freeman DJ, Piche LA, Serratore P. HDL-cholesterol-raising effect of orange juice in subjects with hypercholesterolemia. Am J Clin Nutr. 2000;72(5):1095-1100.
  25. Larsson-Cohn U. Oral contraceptives and vitamins: a review. Am J Obstet Gynecol. 1975;121:84–90.
  26. Molloy TP, Wilson CW. Protein-binding of ascorbic acid. 2. Interaction with acetylsalicylic acid. Int J Vit Nutr Res. 1980;50:387–392.
  27. Peters EM, Goetzsche JM, Grobbelaar B, et al. Vitamin C supplementation reduces the incidence of postrace symptoms of upper-respiratory-tract infection in ultramarathon runners. Am J Clin Nutr. 1993;57:170–174.
  28. Rivers JM, Devine MM. Plasma ascorbic acid concentrations and oral contraceptives. Am J Clin Nutr. 1972;25:684–689.
  29. Rowe DJ, Ko S, Tom XM, et al. Enhanced production of mineralized nodules and collagenous proteins in vitro by calcium ascorbate supplemented with vitamin C metabolites. J Periodontol. 1999; 70:992-929.
  30. Sakagami H, Satoh K, Hakeda Y, Kumegawa M. Apoptosis-inducing activity of vitamin C and vitamin K. Cell Mol Biol. 2000; 46:129-143.
  31. Simon JA, Hudes ES. Relationship of ascorbic acid to blood lead levels. J Amer Med Assoc. 1999; 281:2298-2293.
  32. Simon JA, Hudes ES. Serum ascorbic acid and gallbladder disease prevalence among US adults. The Third National Health and Nutrition Examination Survey (NHANES III). Arch Intern Med. 2000; 160:931-936.
  33. Skaper SD, Fabris M, Ferrari V, et al. quercetin protects cutaneous tissue-associated cell types including sensory neurons from oxidative stress induced by glutathione depletion: cooperative effects of ascorbic acid. Free Rad Biol Med. 1997; 22:669-678.
  34. Taddei S, Virdis A, Ghiadoni L, et al. Vitamin C improves endothelium-dependent vasodilation by restoring nitric oxide activity in essential hypertension. Circulation. 1998; 97:2222-2229.
  35. Tsukaguchi H, Tokui T, Mackenzie B, et al. A family of mammalian Na+-dependent L-ascorbic acid transporters. Nature. 1999; 399:70-75.
  36. Valkonen MM, Kuusi T. Vitamin C prevents the acute atherogenic effects of passive smoking. Free Rad Biol Med. 2000; 28:428-436.
  37. Verlangieri AJ, Fay MJ, Bannon AW. Comparison of L-ascorbic acid and Ester C in the non-ascorbate synthesizing Osteogenic Disorder Shionogi (ODS) rat. Life Sci. 1991; 48:2275-2281.
  38. WangY, Mackenzie B, Tsukaguchi H, et al. Human vitamin C (L-ascorbic acid) transporter SVCT1. Biochem Biophys Res Commun. 2000; 267:488-494.
  39. Webb JL. Nutritional effects of oral contraceptive use: a review. J Reprod Med. 1980;25:150–156.
  40. Wynn V. Vitamins and oral contraceptive use. Lancet. 1975;1:561–564.

Vitamin B6

Common Name: Vitamin B6
Synonyms: Pyridoxal, pyridoxamine, pyridoxine

Overview:

Vitamin B6 is a water soluble vitamin that is involved in a great number of life processes in the body. This member of the vitamin B family is responsible for:

  1. the metabolism of amino acids and glycogen
  2. the synthesis of RNA and DNA
  3. The synthesis of hemoglobin
  4. The synthesis of sphingolipids
  5. The synthesis of the neurotransmitters serotonin, dopamine, norepinephrine, and GABA (gamma-aminobutyric acid).
  6. Vitamin B6 has also shown promise in the treatment of atherosclerosis, immune system function.

Vitamin B6 deficiency is often hard to detect in adults. The classic symptoms of a clinical case of vitamin B deficiency are:

  1. A microcytic, hypochromic anemia (an anemia where the red cells are smaller and paler than normal).
  2. Seizure activity
  3. Seborrheic dermatitis
  4. irritability
  5. Confusions and depression
  6. Chapped and cracked lips
  7. Glossitis (inflammation of the tongue)

Subclinical vitamin B6 deficiency is very common people with malabsorption syndrome, uremia, cancer, heart failure, and cirrhosis, alcoholics and those taking certain medications such as isoniazid, penicillamine, cycloserine, ethionamide and theophylline. Subclinical deficiency is also very common in the elderly who often have very poor eating habits. In the elderly, subclinical deficiency can easily move into the more serious clinical vitamin B6 deficiency.

Benefits

Vitamin B6 has been proven to be extremely helpful:

  1. in inhibiting the binding of steroid hormones, such as estrogen and testosterone to receptor sites on cells. This has implications for diseases that are influenced by these hormones such as breast and prostate cancers
  2. In cardiovascular disease. Even moderate elevation in blood homocysteine levels is associated with an increase in heart attacks and strokes. Several large observational studies showed that a low intake of vitamin B6 correlated with increased blood homocysteine levels. A large prospective study found that risk of heart attack was 33% less in women who took 4.6mg of B6 daily compared to those who only took 1.1mg daily.
  3. In immune system enhancement. Inadequate intake of vitamin B6 has been closely linked to immune system impairment, especially in the elderly. Low B6 levels caused a decrease in the production of lymphocytes (white blood cells that fight infection) and a decrease in interleukin-2 (a protein produced by the body to help white cells do their work). One study found that the amount needed to increase the number of lymphocytes and interleukin-2 were 2.9mg/day for men and 1.9mg/day for women. This is above the RDA limits recommended.
  4. In stopping the decline in cognitive function or Alzheimer’s disease in the elderly and an inadequate intake of vitamin B6. One observational study found that higher levels of vitamin B6 levels were associated with better performance in two tests that measured memory.
  5. In helping to prevent kidney stones. In a large study that involved over 85,000 women, those whose intake of vitamin B6 40mg or more daily had 2/3rds the risk of developing kidney stones as those who consumed 3mg or less.
  6. In treating PMS
  7. In treating morning sickness.

Recommended Dosage:

  1. For the treatment of heart disease and to lower homocysteine levels a dose of 3mg per day is used.
  2. To prevent morning sickness studies have used 10mg per day. This should be determined by consulting with your healthcare provider.
  3. Doses to address the other health conditions discussed earlier ranged from 100mg to as much as 18,000mg per day. Doses of B6 above 200mg/day have been known to cause neurological disorders.

Precautions

As there are known neurological problems that can develop when high levels of B6 are used as a supplement, supplementation with B6 should be supervised by a knowledgeable healthcare provider.

Some people have experienced allergic skin reactions with high doses of vitamin B6

Interactions

If you are taking any of the following medications, supplementing with vitamin B6 should not be done before consulting your health care provider.

  1. Tetracycline absorption is affected by Vitamin B6. This antibiotic and vitamin B6 should be taken at different times.
  2. Vitamin B6 may enhance the effectiveness of tricyclic antidepressants. This is especially true in the elderly.
  3. Vitamin B6 may prove useful in treating the side effects that often accompany antipsychotic medications.
  4. Vitamin B6 supplementation may be needed with the use of:
  • anti-tuberculosis medication such as isoniazid and cycloserine
  • oral contraceptives.
  • Erythropoietin
  • Methotrexate
  • penicillamine
  • Long term use of theophylline

Taking any of these medications has been shown to lower the B6 levels in the body.

  1. Vitamin B6 has been shown to decrease the effectiveness of:
  • Levodopa
  • Phenytoin
  • hydralazine

Web References

  1. http://lpi.oregonstate.edu/infocenter/vitamins/vitaminB6/
  2. http://www.umm.edu/altmed/ConsSupplements/VitaminB6Pyridoxinecs.html
  3. http://en.wikipedia.org/wiki/Vitamin_B6

Printed Reference Material

  1. Alpert JE, Fava M. Nutrition and depression: the role of folate. Nutr Rev. 1997;5(5):145-149.
  2. Alpert JE, Mischoulon D, Nierenberg AA, Fava M. Nutrition and depression: focus on folate. Nutrition. 2000;16:544-581.
  3. Awad AG. Diet and drug interactions in the treatment of mental illness – a review. Can J Psychiatry. 1984;29:609-613.
  4. Baumgaertel A. Alternative and controversial treatments for attention-deficit/hyperactivity disorder. Pediatr Clin North Am. 1999;46(5):977-992.
  5. Bell IR, Edman JS, Morrow FD, et al. Brief communication: Vitamin B1, B2, and B6 augmentation of tricyclic antidepressant treatment in geriatric depression with cognitive dysfunction. J Am Coll Nutr. 1992;11(2):159-163.
  6. Bendich A. The potential for dietary supplements to reduce premenstrual syndrome (PMS) symptoms. J Am Coll Nutr. 2000;19(1):3-12.
  7. Bhagavan HN, Brin M. Drug-vitamin B6 interaction. Curr Concepts iNutr. 1983;12:1-12.
  8. Booth GL, Wang EE. Preventive health care, 2000 update: screening and management of hyperhomocysteinemia for the prevention of coronary artery disease events. The Canadian Task Force on Preventive Health Care. CMAJ. 2000;163(1):21-29.
  9. Boushey CJ, Beresford SA, Omenn GS, Motulsky AG. A quantitative assessment of plasma homocysteine as a risk factor for vascular disease. JAMA. 1995;274:1049-1057.
  10. Brush MG, Bennett T, Hansen K. Pyridoxine in the treatment of premenstrual syndrome: a retrospective survey in 630 patients. Br J Clin Pract. 1998;42:448–452.
  11. Bunker VW. The role of nutrition in osteoporosis. Br J Biomed Sci. 1994;51(3):228-240.
  12. Cardona, PD. [Drug-food interactions]. Nutr Hosp. 1999;14(Suppl 2):129S-140S.
  13. Diegoli MS, da Fonseca AM, Diegoli CA, Pinoltti JA. A double-blind trial of four medications to treat severe premenstrual syndrome. Int J Gynaecol Obstet. 1998;62:63–67.
  14. Ebadi M, Gessert CF, Al Sayegh A. Drug-pyridoxal phosphate interactions. Q Rev Drug Metab Drug Interac. 1982;4(4):289-331.
  15. Eikelboom JW, Lonn E, Genest J, Hankey G, Yusuf S. Homocyst(e)ine and cardiovascular disease: a critical review of the epidemiologic evidence. Ann Intern Med. 1999;131:363-375.
  16. Fabian CJ, Molina R, Slavik M, Dahlberg S, Giri S, Stephens R. Pyridoxine therapy for palmar-plantar erythrodysesthesia associated with continuous 5-fluorouracil infusion. Invest New Drugs. 1990;8(1):57-63.
  17. Frisco S, Jacques PF, Wilson PW, Rosenberg IH, Selhub J. Low circulating vitamin B(6) is associated with elevation of the inflammation marker C-reactive protein independently of plasma homocysteine levels. Circulation. 2001;103(23):2788-2791.
  18. Fugh-Berman A, Cott JM. Dietary supplements and natural products as psychotherapeutic agents. Psychosom Med. 1999;61:712-728.
  19. Heller CA, Friedman PA. Pyridoxine deficiency and peripheral neuropathy associated with long-term phenelzine therapy. Am J Med. 1983;75(5):887-888.
  20. Hines Burnham, et al, eds. Drug Facts and Comparisons. St. Louis, MO: Facts and Comparisons; 2000:18.
  21. Jewell D, Young G. Interventions for nausea and vomiting in early pregnancy (Cochrane Review). Cochrane Database Syst Rev. 2002;(1):CD000145.
  22. Kelly GS. Nutritional and botanical interventions to assist with the adaptation to stress. [Review]. Altern Med Rev. 1999 Aug;4(4):249-265.
  23. Kidd P. Attention deficit / hyperactivity disorder (ADHD) in children: rationale for its integrative management. Altern Med Rev. 2000;5(5):402-428.
  24. Kirschmann GJ, Kirschmann JD. Nutrition Almanac. 4th ed. New York: McGraw-Hill;1996:57-59.
  25. Lerner V, Kaptsan A, Miodownik C, Kotler M. Vitamin B6 in treatment of tardive dyskinesia: a preliminary case series study. Clin Neuropharm. 1999;22(4):241-243.
  26. Lobo A, Naso A, Arheart K, et al. Reduction of homocysteine levels in coronary artery disease by low-dose folic acid combined with levels of vitamins B6 and B12. Am J Cardiol. 1999;83:821–825.
  27. Malinow MR, Bostom AG, Krauss RM. Homocyst(e)ine, diet, and cardiovascular disease. A statement for healthcare professionals from the nutrition committee, American Heart Association. Circulation. 1999;99:178-182.
  28. Morselli B, Neuenschwander B, Perrelet R, Lippunter K. Osteoporosis diet [in German]. Ther Umsch. 2000;57(3):152-160.
  29. Murphy PA. Alternative therapies for nausea and vomiting of pregnancy. Obstet Gynecol. 1998;91:149-155.
  30. Nutrients and Nutritional Agents. In: Kastrup EK, Hines Burnham T, Short RM, et al, eds. Drug Facts and Comparisons. St. Louis, Mo: Facts and Comparisons; 2000:4-5.
  31. Omray A. Evaluation of pharmacokinetic parameters of tetracylcine hydrochloride upon oral administration with vitamin C and vitamin B complex. Hindustan Antibiot Bull. 1981;23(VI):33-37.
  32. Passariello N et al. Effects of pyridoxine alpha-ketoglutarate on blood glucose and lactate in type I and II diabetics. Int J Clin Pharmacol Ther Toxicol. 1983;21(5):252-256.
  33. Rall LC, Meydani SN. Vitamin B6 and immune competence. Nutr Rev. 1993;51(8):217-225
  34. Recommended Dietary Allowance. American Academy of Sciences. Accessed at www.nal.usda.gov/fnic/Dietary/rda.html on January 8, 1999.
  35. Rimm EB, Willett WC, Hu FB, et al. Folate and vitamin B6 from diet and supplements in relation to risk of coronary heart disease among women. JAMA. 1998;279:359-364.
  36. Rock CL, Vasantharajan S. Vitamin status of eating disorder patients: Relationship to clinical indices and effect of treatment. Int J Eating Disord. 1995;18:257-262.
  37. Robinson K, Arheart K, Refsum H, et al. Low circulating folate and vitamin B6 concentrations. Risk factors for stroke, peripheral vascular disease, and coronary artery disease. Circulation. 1998;97:437-443.
  38. Rumsby PC, Shepherd DM. The effect of penicillamine on vitamin B6 function in man. Biochem Pharmacol. 1981;30(22):3051-3053.
  39. Schnyder G. Decreased rate of coronary restenosis after lowering of plasma homocysteine levels. N Eng J Med. 2001;345(22):1593-1600.
  40. Seelig MS. Auto-immune complications of D-penicillamine – a possible result of zinc and magnesium depletion and of pyridoxine inactivation. J Am Coll Nutr. 1982;1(2):207-214.
  41. Shimizu T, Maeda S, Arakawa H, et al. Relation between theophylline and circulating vitamin levels in children with asthma. Pharmacol. 1996;53:384-389.
  42. Shor-Posner G, Feaster D, Blaney NT. Impact of vitamin B6 status on psychological distress in a longitudinal study of HIV-1 infection. Int J Psychiatry Med. 1994;24(3):209-222
  43. Shumann K. Interactions between drugs and vitamins in advanced age. Int J Vit Nutr Res. 1999;69(3):173-178.
  44. Vail DM, Chun R, Thamm DH, Garrett LD, Cooley AJ, Obradovich JE. Efficacy of pyridoxine to ameliorate the cutaneous toxicity associated with doxorubicin containing pegylated (Stealth) liposomes: a randomized, double-blind clinical trial using a canine model. Clin Cancer Res. 1998;4(6):1567-1571.
  45. Vermeulen EGJ, Stehouwer CDA, Twisk JWR, et al. Effect of homocysteine-lowering treatment with folic acid plus vitamin B6 on progression of subclinical atherosclerosis: a randomised, placebo-controlled trial. Lancet. 2000;355:517-522.
  46. Vidrio H. Interaction with pyridoxal as a possible mechanism of hydralazine hypotension. J Cardiovasc Pharmacol. 1990;15(1):150-156.
    Wada M. The adverse reactions of anti-tuberculosis drugs and its management [in Japanese]. Nippon Rinsho. 1998;56(12):3091-3095.
  47. Weber P. The role of vitamins in the prevention of osteoporosis – a brief status report. International Journal of Vitaminology and Nutrition Research. 1999;69(3):194-197.
  48. Wyatt KM, Dimmock PW, Jones PW, Shaughn O'Brien PM. Efficacy of vitamin B6 in the treatment of premenstrual syndrome: a systematic review. BMJ. 1999;318(7195):1375-1381.

Vitamin B5

Called Pantothenic Acid, Vitamin B5 is part of the B Complex. It is needed for the breakdown of carbohydrates, proteins, and fats. Vitamin B5 can be found in peas and beans (except green beans), lean meat, poultry, fish and whole-grain cereals.

Vitamin B3

Vitamin B3 is also known as niacin. It assists in the functioning of the digestive system, skin, and nerves. It is also plays an important role in converting food to energy. Niacin is found in dairy products, poultry, fish, lean meats, nuts, and eggs. Enriched breads and cereals also supply some niacin.

Vitamin B2

Also known as riboflavin, Vitamin B2 is required by the body for oxygen use and the metabolism of amino acids, fatty acids, and carbohydrates. It is important for body growth and red blood cell production. Meats, eggs, legumes, nuts, green leafy vegetables, and dairy products are all good sources of Vitamin B2.

Vitamin B12

Common Name: Vitamin B12
Synonyms: Cobalamin

Overview:

Vitamin B12 is one of the water soluble B vitamins. Its other name, cobsosmin, indicates that this vitamin contains cobalt in its chemical structure. Of allthe vitamins B12 is the most complex. In chemical structure B12 is closely related to hemoglobin and chlorophyll. B12 is part of what is called the B complex family of vitamins. This complex is essential in the breakdown of fats and proteins. They also play an important role in keeping muscles toned, maintaining the lining of the gastrointestinal tract. They also promote the health of the nervous system, skin, eyes, mouth liver and hair.

B12 not only plays an important role in nerve health but aids in production of DNA and RNA. It also works together with folate in the formation of red blood cells while involved in improving the functioning of the immune system. It also helps the body to withstand stressful conditions. Together with vitamins B6 and folate, B12 helps to control the levels of homocysteine. Elevated homocysteine levels have been linked to an increased risk of heart disease, depression and maybe even Alzheimer’s.

In order for Vitamin B12 to be absorbed by the body, the digestive track must contain what it known as “intrinsic factor. Without this factor, B12 can not be absorbed and a vitamin B12 deficiency is the result. A deficiency of vitamin B12 causes a myriad of symptoms including:

  • Fatigue
  • Shortness of breath
  • Diarrhea
  • Nervousness
  • Numbness or tingling in the fingers and toes.

People who develop pernicious anemia lack the intrinsic factor and therefore cannot absorb vitamin B12. They need to take B12 by injection to ensure that they get enough of this vitamin. It has been found that in people over the age of 60 the neurological symptoms of vitamin B12 deficiency may occur without anemia. The symptoms of this type of B12 deficiency include tingling and numbness in the arms and legs, loss abnormal gait, irritability, depression and loss of cognitive functions (inability to concentrate, memory loss) and dementia. Vitamin B12 deficiency has also been associated with age related hearing loss.

Benefits

The most important use of vitamin B12 is in the treatment of pernicious anemia. Lack of the “intrinsic factor” keeps the vitamin B12 from being absorbed into the body. Eventually this lack of the B vitamin results in a severe anemia. The only treatment for pernicious anemia is vitamin B12 injections for an entire lifetime. Vitamin B12 supplements are especially important in the elderly and those who have undergone gastric surgery. It has been estimated that between 10-15% of people over 60 have a subtle vitamin B12 deficiency. This is because as we age, the stomach production of acid-pepsin decreases. The acid-pepsin combination is what frees vitamin B12 from the foods we eat.

It was once thought that the neurological and physical symptoms of vitamin B12 deficeincy did not occur separately from the development of pernicious anemia. That has now been proven wrong. The neurological symptoms alone are the most common form of vitamin B12 deficiencies. Supplementation with vitamin B12 successfully reverses the memory loss that accompanies the lack of vitamin B12.

Researchers have shown that people with high levels of homocysteine in their blood are 1.7 times more likely to suffer from cardiovascular disease and 2.5 times more likely to suffer a stoke then those whose homocysteine levels are normal. The B vitamins, especially B12 and folate have a strong influence in the maintaining of a normal homocysteine level.

B12 is part of the complex of B vitamins and folate that are important in maintaining eye health and preventing the formation of cataracts. Supplementing with the B vitamins, folate, plus the antioxidants A,C, and E may offer even more protection from cataract development.

Dietary Sources

Fish
 Fish
Dairy
 Dairy
Eggs
 Eggs
Beef and Pork
 Beef and Pork
Organ MeatOrgan Meat


Recommended Dosage:

Daily recommendations for dietary vitamin B12 are listed below.

Pediatric

  • Newborns to 6 months: 0.4 mcg (adequate intake)
  • Infants 6 months to 1 year: 0.5 mcg (adequate intake)
  • Children 1 to 3 years: 0.9 mcg (RDA)
  • Children 4 to 8 years: 1.2 mcg (RDA)
  • Children 9 to 13 years: 1.8 mcg (RDA)
  • Adolescents 14 to 18 years: 2.4 mcg (RDA)

Adult

  • 19 years and older: 2.4 mcg (RDA)*
  • Pregnant females: 2.6 mcg (RDA)
  • Breastfeeding females: 2.8 mcg (RDA)

10-30% of older people do not absorb B12 from food very efficiently. It is recommended that those older than 50 years should add B12 supplements to their diets to ensure proper levels of vitamin B12 in their system.

Contra-indications

  • Vitamin B12 is considered safe and non-toxic. Taking a single B vitamin for long periods of time can cause an imbalance in the entire complex of B vitamins. When supplementing with a particular B vitamin it is recommended that a B complex is taken as well.
  • The B vitamins can interfere with the absorption of tetracycline. Because of this take the B vitamin at a different time than the antibiotic.
  • long term use of antibiotics can deplete the stores of B vitamins. Talk with your healthcare practitioner about supplement with a B complex when on long term antibiotic therapy.
  • Taking stomach acid reducers can decrease the absorption of B12.Medications used in treating cancer, particularly methotrexate, can lower the blood levels of vitamin B12.
  • Taking metformin for diabetes has been shown to lower the blood levels of B12.
  • Phenobarbital and Phenytoin used for the treatment of seizure disorders may interfere with the body’s ability to use vitamin B12.

Web References

  1. http://www.umm.edu/altmed/ConsSupplements/VitaminB12Cobalamincs.html
  2. http://en.wikipedia.org/wiki/Vitamin_B12
  3. http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/vit_0262.shtml
  4. http://healthlibrary.epnet.com/GetContent.aspx?token=e0498803-7f62-4563-8d47-5fe33da65dd4&chunkiid=33802#B

Printed Reference Material

  1. Adachi S, Kawamoto T, Otsuka M, Todoroki T, Fukao K. Enteral vitamin B12 supplements reverse postgastrectomy B12 deficiency. Ann Surg. 2000;232(2):199-201.
  2. Alpert JE, Fava M. Nutrition and depression: the role of folate. Nutrition Rev. 1997;5(5):145-149.
  3. Alpert JE, Mischoulon D, Nierenberg AA, Fava M. Nutrition and depression: focus on folate. Nutrition. 2000;16:544-581.
  4. Antoon AY, Donovan DK. Burn Injuries. In: Behrman RE, Kliegman RM, Jenson HB, eds. Nelson Textbook of Pediatrics. Philadelphia, Pa: W.B. Saunders Company; 2000:287-294.
  5. Bauman WA, Shaw S, Jayatilleke E, Spungen AM, Herbert V. Increased intake of calcium reverses vitamin B12 malabsorption induced by metformin. Diabetes Care. 2000;13(9):1227-1231.
  6. Booth GL, Wang EE. Preventive health care, 2000 update: screening and management of hyperhomocysteinemia for the prevention of coronary artery disease events. The Canadian Task Force on Preventive Health Care. CMAJ. 2000;163(1):21-29.
  7. Bottiglieri T, Laundy M, Crellin R, Toone BK, Carney MW, Reynolds EH. Homocysteine, folate, methylation, and monoamine metabolism in depression. J Neurol Neurosurg Psychiatry. 2000;69(2):228-232.
  8. Bottiglieri T. Folate, vitamin B12, and neuropsychiatric disorders. Nutrition Rev. 1996;54(12):382-390.
  9. Boushey CJ, Beresford SA, Omenn GS, Motulsky AG. A quantitative assessment of plasma homocysteine as a risk factor for vascular disease. JAMA. 1995;274:1049-1057.
  10. Brattstrom LE, Hultberg BL, Hardebo JE. Folic acid responsive postmenopausal homocysteinemia. Metabolism. 1985;34(11):1073-1077.
  11. Bunker VW. The role of nutrition in osteoporosis. Br J Biomed Sci. 1994;51(3):228-240.
  12. Carmel R. Cobalamin, the stomach and aging. Am J Clin Nutr. 1997;66(4):750-759.
  13. Choi SW. Vitamin B12 deficiency: a new risk factor for breast cancer? [Review]. Nutr Rev. 1999;57(8):250-253.
  14. Clarke R, Smith AD, Jobst KA, Refsum H, Sutton L, Veland PM. Folate, vitamin B12, and serum total homocysteine levels in confirmed Alzheimer disease. Arch Neurol. 1998;55:1449-1455.
  15. Committee on Dietary Allowances. Recommended Dietary Allowances. National Academy of Sciences. Accessed at www.nal.usda.gov/fnic/Dietary/rda.html on January 8, 1999.
  16. Dastur D, Dave U. Effect of prolonged anticonvulsant medication in epileptic patients: serum lipids, vitamins B6, B12 and folic acid, proteins and fine structure of liver. Epilepsia. 1987;28:147-159.
  17. De-Souza DA, Greene LJ. Pharmacological nutrition after burn injury. J Nutr. 1998;128:797-803.
  18. Eikelboom JW, Lonn E, Genest J, Hankey G, Yusuf S. Homocyst(e)ine and cardiovascular disease: a critical review of the epidemiologic evidence. Ann Intern Med. 1999;131:363-375.
  19. Ekhard ZE, Filer LJ, eds. Present Knowled