Transcript Water Soluble Vitamins

Water Soluble Vitamins
The “supporting” cast
Vitamins in general
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•
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vital
individual units
assist enzymes with the release of energy
measured in micrograms (ug) or milligrams
(mg)
• organic
– can be destroyed by heat, UV, oxygen
• available in food
• bioavailability
– quantity and
• digestion efficiency
• nutrition status
• other foods
• food preparation
• source
Solubility
• water soluble
– 8 B vitamins
– vitamin C
• fat soluble
vitamins A, D, E, and K
Water Soluble Vitamins
B, C
• found in water parts of food
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– easily destroyed or minimized by certain
cooking processes
move directly to blood
freely circulate
excesses are removed by kidney
– too many can overwhelm the system
regular intake
Fat Soluble
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A, D, E, K
found in fats and oils
enter the lymph, then the blood
held in fatty tissues
remain in fat storage
may reach toxic levels
Essential and Harmful
Too much: vitamin A – headaches, fatigue
vitamin D – weakness, calcium in arteries
vitamin E – increased cholesterol levels
Blindness: vitamin
A deficiency
Pellagra: niacin (B
vitamin) deficiency
Rickets: vitamin
D deficiency
B Vitamins
• thiamin (B1)
– coenzyme in energy
metabolism
– whole grains
• riboflavin (B2)
– energy metabolism
– milk producst
Enzyme
Coenzyme
Vitamin
CD
A
Vitamin
Coenzyme
Enzyme
B Vitamins
• niacin
– energy metabolism
– milk, eggs, meat, fish
• biotin
– fat synthesis, amino acid metabolism,
glycogen synthesis
– widespread in food
B Vitamins
• pantothenic acid
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•
– energy metabolism
– widespread in food
vitamin B6
– amino acid and fatty acid metabolism
– meat, fish, potatoes
folate
– folic acid
– DNA synthesis and new cell formation
– fortified grains, leafy vegetables
B Vitamins
• Vitamin B12
– closely related to folate
• nerve cell maintanence
– each are dependent on each other
– animal products
B Vitamins
• work together in energy
metabolism
– energy releasing
reaction
– build cells
– dependent on each
other
Copyright 2005 Wadsworth Group, a division of Thomson Learning
Copyright 2005 Wadsworth Group, a division of Thomson Learning
Copyright 2005 Wadsworth Group, a division of Thomson Learning
Copyright 2005 Wadsworth Group, a division of Thomson Learning
Vitamin C: Ascorbic Acid
• antioxidant
– defends against free radicals
• unstable and reactive (free electron)
• vitamin C sacrifices an electron,
making substance stable
• cofactor
– in collagen formation
• structural protein
Vitamin C
• cure for the common cold
– controversial
– does deactivate histamine
• may help in preventing cancer, heart
disease, cataracts
– difficult to study
Copyright 2005 Wadsworth Group, a division of Thomson Learning
Vitamin B and C Recommendations
VITAMIN
RDA
UPPER LEVEL
thiamin (B1)
riboflavin (B2)
niacin
biotin
pantothenic acid
vitamin B6
folate (folic acid)
vitamin B12
vitamin C
smokers
1.1-1.2 mg
1.1-1.3 mg
14-16 mg
30ug
5 mg
1.3 mg
400 ug
2.4 ug
75-90 mg
+ 35 mg
none
none
35 mg
none
none
100 mg
1000 ug
none
2000 mg