Download Vitamins

 Are a group of organic nutrients required in small quantities for a variety of
biochemical functions, forproper metabolism, to protect health, and for nor
mal growth and activity of the body. Also for the prevention of a number of
diseases.
 Most vitamins cannot be synthesized by the body. They must be supplied in
the diet.
 Vitamins are usually classified as water soluble or fat soluble
Types of Vitamins:
1. Fat-Soluble Vitamins:
Properties:
 Fat soluble vitamins often have very specialized functions
 Necessary for the function or structural integrity of specific body
tissues and membranes.
 Can be retained in the body, and are not leached out quickly.
 Apolar hydrophobic compounds that can only be absorbed
efficiently when there is normal fat absorption.
 Unlike water soluble vitamins, an excess of a fat soluble vitamin
can be just as harmful as a deficiency
2. Water-Soluble Vitamins:
Properties:
– Act as catalysts and enzyme cofactors in metabolic processes and
energy transfer.
– Are not stored in the body (excreted fairly rapidly) and must be
replaced each day.
– These vitamins are easily destroyed or washed out during food
storage and preparation (overcooking)
– Water soluble vitamins do not accumulate in the body, so regular
supplies are necessary
FAT – SOLUBLE VITAMINS
Vitamin A:
Vitamin A is also known as retinol
Vitamin A Sources:
 Commonly found in cod liver oil, green vegetables, fruit dairy products,
eggs, and liver
 Carrots indirectly serve as a source of vitamin A since they contain b
carotene which the body readily converts to vitamin A
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Vitamin A Functions:
 Role in aiding in night vision.
 Retinol is oxidized to retinal, which combines with the protein opsin to
form rhodopsin. Rhodopsin is the active agent which converts light signals
to electrical impulses that the optic nerve transmits to the brain
Vitamin A Deficiencies:
 A deficiency in vitamin A results in night blindness.
 The most serious deficiency results in a condition known as Xeropthalmia, a
severe form of conjunctivitius or blindness.
Excess of Vitamin A:
 Carotenemia; Bleeding; Hepatosplenomegaly (rare)
2-Vitamin D (Calciferol)
Sources:
 Dairy products, eggs, Fish liver oils. Synthesized by sunlight action on skin.
 Unlike other vitamins, the body synthesizes vitamin D in the skin through
the action of ultraviolet light on 7-dehydrochlosterol
Vitamin D Functions:
 Vitamin D is an important regulator of calcium metabolism.
 It is involved in the uptake of calcium and phosphate ions from food into
the body.
 It is necessary for the proper formation of bone structures and teeth.
Vitamin D Deficiencies:
 Rickets (children)
 Osteomalacia (adults)
Excess of Vitamin D :
 Hypercalcemia leading to metastatic calcification and renal damage (rare).
3- Vitamin K:
Function:
 Blood clotting, Required for synthesis of Prothrombin (II) and clotting
factors VII, IX and X.
Sources:
 Green leafy vegetables, liver; Naturally produced by bacteria in the
intestine.
Deficiencies:
 Hemorrhagic disease
Water-Soluble Vitamins:
1- B12 (Cyanocobalamin)
Food source:
Red meats, Liver, eggs, dairy products and fish
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Function:
Nucleic acid production
Deficincy:
Megaloblastic anemia (Pernicious anemia);neuropathy.
2- Vitamin C (Ascorbic Acid)
Sources:
 Citrus fruits, green leafy vegetables, tomatoes
Function:
 Collagen formation in teeth, bone, and connective tissue of blood vessels
 May help in resisting infection
 Absorption of iron, calcium, folacin
 Ascorbic acid is a great antioxidant
 Works with vitamin E as a free-radical scavenger.
Deficincy:
 Scurvy (breakdown of skin, blood vessels, and teeth)
 Impaired wound healing.
 *Vitamin C deficiency- often results secondary to hyperparathyroidism
Excess:
 None known, minimal-possibly urinary calculi, gastrointestinal complaints
including diarrhea, nausea and abdominal cramps
3- Folic Acid (Folacin)
Source:
Whole-wheat foods, green vegetables, legumes, organ meats, fish, citrus fruits.
Function:
Nucleic acid metabolism
Deficiency:
Megaloblastic anemia (Pernicious anemia)
Excess:
None
Other vitamins:
1. Vitamin P (bioflavonoids, citrin):
a. Helps increase strength of capillaries found in the mesocarp
(tasteless, spongy, white layer beneath the rind) of lemon fruit.
2. Vitamin F (unsaturated fatty acids):
a. Is important in respiration of vital organs.
i. -helps maintain resilience and lubrication of cells.
ii. -helps regulate blood coagulation.
iii. -is essential for normal glandular activity.
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3. Vitamin B13 (Orotic acid):
a. is needed for the metabolism of some B-vitamins
4. Vitamin B15 (Pangamic acid):
a. helps eliminate hypoxia helps promote CHON metabolism stimulates
nervous and glandular system
5. Vitamin B17 (Laetrile):
– has been linked to cancer prevention
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