Facts About Vitamins
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FAT-SOLUBLE VITAMINS
     Vitamin A
     Vitamin D
     Vitamin E
     Vitamin K
WATER-SOLUBLE VITAMINS
     Thiamin
     Riboflavin
     Niacin
     Vitamin B6
     Vitamin B12
     Folate
     Pantothenic acid
     Biotin
     Vitamin C 

FAT-SOLUBLE VITAMINS
Vitamin A
        Sources
            1. liver, carrots, fortified milk, sweet potatoes, green leafy vegetables
        Uses
            1. synthesis of rhodopsin for rods in retina
            2. strong skin
            3. production of mucus by mucus membranes
            4. functioning of T-lymphocytes
            5. synthetic reactions for cell growth and cell reproduction and bone turnover
            6. reduce effects of oxidizing agents like free radicals ( e.g., protects cell membranes, reduces risk of cancer)
        Recommended dietary intake
            1. 800-1,000 micrograms per day
            2. 600-700 micrograms per day for the elderly
        Causes of deficiencies
            1. inadequate eating
            2. dietary deficiency in vegetables, fats
            3. diseases of liver, small intestine, gall bladder (low bile)
            4. mineral oil laxatives block absorption by holding vitamin A in intestine
            5. zinc deficiency blocks release of vitamin A from liver into blood
            6. anti-inflammatory steroid therapy (e.g., for osteoarthritis)
        Results from deficiencies
            1. dry skin
            2. increased risk of infection from weak skin and epithelia, and decreased mucus on mucus membranes
            3. night blindness, slower dark adaptation, greater sensitivity to glare and flashes of light
            4. thickened conjunctiva causes decreased vision, blindness
            5. reduced immune defense function
            6. increased risk of cancer
        Causes of excesses
            1. supplements
            2. possible increased absorption, age changes or disease in liver causing decreased removal from blood
        Results from excesses
            1. headaches
            2. hair loss, dry skin, itchy skin
            3. liver malfunction
            4. muscle, bone, and joint abnormalities and pain
            5. low WBC levels
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Vitamin D
        Sources
            1. synthesized by the skin, activated by the liver and kidneys
            2. fortified milk, bread, juices, and other fortified foods, oily fish and fish oils
        Uses
            1. increases absorption of calcium and phosphorous by small intestine
            2. assists bone maintenance through bone matrix turnover
            3. increases kidney reabsorption of calcium
            4. increased mobilization of calcium from bones
            5. affects calcium transport in many cells (brain, bone, pituitary)
            6. part of therapy for osteoporosis
        Recommended dietary intake
            1. 5 micrograms per day
            2. more than 5 micrograms per day for the elderly
        Causes of deficiencies
            1. inadequate eating
            2. low fat diet
            3. less sun exposure, less skin synthesis, and less kidney activation
            4. in women, decreased estrogen and possible decreased parathormone levels cause less activation by the kidney
            5. laxatives like mineral oil bind vitamin D in intestine cause decreased absorption
            6. anti-inflammatory steroid therapy (e.g., for osteoarthritis)
        Results from deficiencies
            1. decreased calcium absorption by the small intestine
            2. increased risk of osteoporosis
        Causes of excesses
            1. vitamin supplements
            2. vitamin D therapy for osteoporosis
        Results from excesses
            1. hypercalcemia causes calcium deposits
            2. hypercalciuria causes urinary stones
            3. weakness, brain malfunctions
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Vitamin E
        Sources
            1. vegetable oils, peaches, asparagus
        Uses
            1. antioxidant against harmful effects of free radicals and other oxidants, ex. lungs, vitamin A, double bonds in unsaturated fatty acids (e.g., cell membranes)
            2. decreases risk of cancer
            3. important for iron metabolism, maintaining nerve tissue, immune function
            4. must be replaced since vitamin E molecules are destroyed when countering oxidizing agents (reduces oxidizing agents)
        Recommended dietary intake
            1. 8-10 mg per day
        Causes of deficiencies
            1. inadequate eating
            2. smoking destroys vitamin E in lungs
        Results from deficiencies
            1. hemolysis by oxidizing agents altering fatty acids in cell membranes cause anemia
            2. nervous system abnormalities
        Causes of excesses
            1. supplements
        Results from excesses
            1. hemorrhaging from decreased vitamin K activity
            2. nervous system malfunction cause headache, fatigue, nausea
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Vitamin K
        Sources
            1. synthesized by large intestine bacteria
            2. green leafy vegetables, peas, green beans, liver
        Uses
            1. synthesis of blood clotting materials (e.g., prothrombin) by the liver
        Recommended dietary intake
            1. 65-80 micrograms per day
        Causes of deficiencies
            1. antibiotics killing large intestine bacteria
            2. low fat absorption
            3. mineral oil laxatives block absorption
        Results from deficiencies
            1. bruising
            2. bruising, anemia from bleeding
        Causes of excesses
            1. supplements
        Results from excesses
            1. anemia and jaundice
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WATER-SOLUBLE VITAMINS

Thiamin
        Sources
            1. thiamin-enriched foods, pork, whole grains
        Uses
            1. assists in getting carbohydrate fragments into the Krebs cycle and with other Krebs cycle reactions to get energy from amino acid fragments
            2. helps synthesize neurotransmitters (e.g., acetylcholine)
        Recommended dietary intake
            1. 1.1-1.5 mg per day
            2. 1.0-1.2 mg per day for the elderly
        Causes of deficiencies
            1. inadequate eating
            2. alcohol reduces thiamin absorption and use
            3. regular consumption of tea, which contains thiamin antagonists
        Results from deficiencies
            1. low energy causes weakness
            2. brain and neuron malfunction
        Causes of excesses
            1. rare
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Riboflavin
        Sources
            1. dairy products
        Uses
            1. make FAD for energy reactions in mitochondria (carbohydrate, fatty acid, and amino acid breakdown)
        Recommended dietary intake
            1. 1.3-1.7 mg per day
            2. 1.0-1.2 mg per day for the elderly
        Causes of deficiencies
            1. low dairy products in diet
            2. alcoholism causing poor diet
            3. estrogen therapy
        Results from deficiencies
            1. inflammation of the mouth and skin
            2. vision problems
         Causes of excesses
            1. none
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Niacin
        Sources
            1. mushrooms, meats, fish, grains, peanuts
        Uses
            1. make NAD and NADH to get energy from carbohydrates, fatty acids, and amino acids
            2. used in many synthesis reactions for lipid and proteins
            3. high doses lowers blood cholesterol
        Recommended dietary intake
            1. 15-19 mg per day
            2. 13-15 mg per day for the elderly
        Causes of deficiencies
            1. inadequate eating
        Results from deficiencies
            1. weakness
            2. brain malfunction, dementia
            3. skin rashes
            4. diarrhea
        Causes of excesses
            1. supplements to lower blood cholesterol
        Results from excesses
            1. redness (vasodilation) and itching of the skin
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Vitamin B6
        Sources
            1. meat, fish, bananas, broccoli, spinach
        Uses
            1. used in many reactions to obtain energy and to manufacture molecules
            2. converting one amino acid to another
            3. synthesizing amino acids
            4. synthesis of hemoglobin, WBCs, neurotransmitters (e.g., norepinephrine, GABA, serotonin)
        Recommended dietary intake
            1. 1.6-2.0 mg per day
            2. 2.0 mg per day for the elderly
            3. increases recommended for alcoholics, smokers, women on estrogen therapy
        Causes of deficiencies
            1. inadequate eating
            2. smoking
            3. estrogen therapy
            4. alcoholism causes decreased absorption and interconversion of vitamin B-6 molecules, increased destruction of vitamin B6
        Results from deficiencies
            1. anemia
            2. excess blood homocysteine
            3. CNS malfunction
            4. low immune response
            5. poor cell and tissue maintenance and repair
        Causes of excesses
            1. supplements for any reason or to treat PMS in premenopausal women
        Results from excesses
            1. nerve damage
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Vitamin B12
        Sources
            1. meats, milk
        Uses
            1. assists folate for DNA and RNA synthesis
            2. RBC synthesis
            3. break down fatty acids for energy
            4. maintaining myelin sheath
        Recommended dietary intake
            1. 2.0 micrograms per day
            2. 3.0 mg per day for some elderly
        Causes of deficiencies
            1. inadequate eating
            2. decreased stomach acid or intrinsic factor production
            3. atrophic gastritis
            4. small intestine disease
        Results from deficiencies
            1. anemia
            2. excess blood homocysteine
            3. poor nerve function
        Causes of excesses
            1. none
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Folate
        Sources
            1. fresh fruits, raw or lightly cooked green leafy vegetables, orange juice
        Uses
            1. synthesis of some amino acids and parts of DNA and RNA molecules
        Recommended dietary intake
            1. 180-200 micrograms per day
        Causes of deficiencies
            1. inadequate eating
            2. alcoholism decreases folate absorption
            3. decreased stomach acid may decrease absorption
            4. overcooking vegetables
        Results from deficiencies
            1. poor cell reproduction
            2. anemia from production of abnormal RBCs
            3. abnormal CNS and digestive system functioning
            4. hair loss
        Causes of excesses
            1. none
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Pantothenic acid
        Sources
            1. mushrooms, meats, most vegetables
        Uses
            1. synthesis of molecules and for transferring fragments into the Krebs cycle (for energy and synthesis)
        Recommended dietary intake
            1. 4-7 mg per day
        Causes of deficiencies
            1. inadequate eating
        Results from deficiencies
            1. fatigue
            2. digestive system discomfort
            3. muscle cramps
            4. increased risk of infection
        Causes of excesses
            1. none
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Biotin
        Sources
            1. cheese, egg yolks, cauliflower
            2. made by intestinal bacteria
        Uses
            1. assisting entrance of molecular fragments into the Krebs cycle (energy and synthesis)
        Recommended dietary intake
            1. 30-100 micrograms per day
        Causes of deficiencies
            1. inadequate eating
        Results from deficiencies
            1. inflamed skin
            2. weakness
            3. anemia
            4. depression
            5. digestive system discomfort
        Causes of excesses
            1. supplements
        Results from excesses
            1. unknown
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Vitamin C
        Sources
            1. citrus fruits, other fresh fruits, green vegetables
        Uses
            1. assists in protein synthesis, especially collagen synthesis
            2. assist cell-mediated part of immune response
            3. activated iron and other minerals that assist enzyme activities
            4. anti-oxidant (e.g., protects lungs, reduces cancer risk)
            5. neutralizes carcinogens from nitrates in foods
            6. assists iron absorption
            7. assists synthesis of many substances (e.g., norepinephrine, steroid hormones, parts of DNA, thyroid hormone)
            8. high levels reduce blood cholesterol and LDLs in some people
        Recommended dietary intake
            1. 60 mg per day
        Causes of deficiencies
            1. inadequate eating
            2. smoking destroys vitamin C in the lungs
            3. overcooking or washing foods
            4. cancer
            5. anti-inflammatory steroid therapy (e.g., for osteoarthritis)
        Results from deficiencies
            1. poor healing
            2. edema
        Causes of excesses
            1. supplements
        Results from excesses
            1. diarrhea
            2. excess iron absorption
            3. urinary system stones
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© Copyright 1999 - Augustine G. DiGiovanna - All rights reserved.
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