Page Index
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
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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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 2020: Augustine G. DiGiovanna, Ph.D.,
Salisbury University, Maryland
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