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VITAMINS
Vitamins - are a group of organic nutrients
required in small quantities for a variety of biochemical functions, for proper metabolism, to protect health, and for normal growth and activity of the body.
1. Fat-Soluble Vitamins
2. Water-Soluble Vitamins
Types of Vitamins
1. Fat-Soluble VitaminsProperties:– Necessary for the function or structural
integrity of specific body tissues and membranes.
– Can be retained in the body.– Apolar hydrophobic compounds that can only
be absorbed efficiently when there is normal fat absorption.
2. Water-Soluble VitaminsProperties:
– 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)
FAT – SOLUBLEVITAMINS
Vitamin
Physiologic Importance
Deficiency Excess RDA
Food source
A(Retinol,
β-carotene)
• Component of light-sensitive pigments in eye• epithelial tissue maintenance• regulation of gene expression and cell diffentiation
• Night blindness• Xerophthalmia• Associated with Bitot's spots, keratomalacia, follicular hyperkeratosis
Carotenemia;
Bleeding;
Hepatospleno-
megaly (rare).
5,000 IU
Green vegetables, dairy products, eggs, liver
D(Calciferol)
• initiates calcium absorption in intestine and causes bone mineralization• Promotes hardening of bones and teeth
• Rickets (children)• Osteomalacia (adults)
• Hypercal-cemia leading to metastatic calcification and renal damage (rare).
400 IU for adults
Dairy products, eggs,
Fish liver oils. Synthesized by sunlight action on skin.
E (Tocopherols, tocotrienols)
• Antioxidant (Protects vitamins A and C, fatty acids and red blood cell membranes from destruction due to oxidation)
• Possibly anemia• Serious neurologic dysfunction (extremely rare)• Increase hemolysis of red blood cells
Muscular dystrophy
None 15 IU
(Men)
12 IU
(Women)
Margarine, seeds, green leafy vegetables
K (Phylloquinone, menaquinones)
• Blood clotting
Required for synthesis of Prothrombin (II) and clotting factors VII, IX and X.
• Hemorrhagic disease• Hypoprothrom-binemia resulting in bleeding tendency
Hemolytic anemia (rare)
No RDA.
300-500 mcg is considered adequate
• Green leafy vegetables, liver;• Naturally produced by bacteria in the intestine.
WATER-SOLUBLEVITAMINS
Vitamin
Physiologic Importance
Deficiency
Excess
RDA Food source
B1(Thiamine)
• catalyst in carbohydrate metabolism, nerve and heart function
• Beriberi (wet and dry)• Wernicke's encephalopathy• Korsakoff's psychosis
Transient flushing, dizziness
• 0.5
mg/1000
calories
consumed
• 1.6 mg for adults
Organ meats, pork, whole grains, legumes, cereals, yeast, egg yolk
B2(Riboflavin,
vitamin G)
• essential part of enzyme systems concerned with oxidation and reduction in living cells.• Constituent of flavoproteins
• Eye irritation, corneal vascularization, inflammation and breakdown of skin cells• cheilosis, glossitis, angular stomatitis
None. • 0.55
mg/1000
calories
consumed.
•1.6 mg for adults
Milk products, liver, eggs, grains, legumes, dark green
vegetables, cereals, fruit, yeast
* Vit. B2 deficiency
B3(Niacin,
Nicotinamide, Nicotinic acid)
• Oxidation-reduction reactions in cellular respiration• Functional part of NAD and NADP.
• Pellagra (skin and gastrointestinal disorders, nerve inflammation, mental disorders)
• Flushing due to vasodilation occurs with intravenous injection (rare).• Abnormal liver function; cramps; nausea
• 6.6 mg/1000 calories consumed.
• 18 mg (male)•13 mg (female)
Liver, lean meats, poultry, fish, whole and enriched grain products, legumes
B5(Pantothenic Acid)
• Energy metabolismneeded to form coenzyme-A (CoA), and is critical in the metabolism and synthesis of carbohydrates, proteins, and fats.• For pyruvate oxidation and biological acetylations
Fatigue, loss of coordination
None known
0.5-10.0 mg for both adults and children is adequate
Milk products, liver, kidney, eggs, whole grains, legumes; also made by intestinal bacteria.
B6(Pyridoxine,
Pyridoxal,
Pyridoxamine)
• Aids in amino acid metabolism, absorption; aids in red blood cell formation; helps body use fats.• Coenzyme for decarboxylase and transaminase systems
• Convulsions, irritability, kidney stones• Glossitis; blepharitis; dermatitis; cheilosis; peripheral neuropathy; sideroblastic anemia.
Transient paresthesias
• 0.2
mg/100mg
CHON
• 1.8 mg (male)• 1.5 mg (female)
Whole-grain cereals, vegetables, meats
B12(Cyanocobalamin)
• Nucleic acid production
• Megaloblastic anemia (Pernicious anemia);• Subacute combined degeneration of spinal cord; peripheral neuropathy.
None. 3 mcg for adults Red meats, Liver, eggs, dairy products and fish
Biotin
(Vitamin H)
• Fat synthesis and amino acid metabolism• Part of the enzyme systems participating in conversion of pyruvate to oxaloacetate (gluconeogene-sis)
• Depression, fatigue, nausea, alopecia, dermatitis, atrophy of lingual papillae, muscle pain, paresthesias, hypercholesterolemia, and electrocardiogram abnormalities
None known
150-300 mcg usually meets daily needs
Liver, kidney, egg yolk, milk, most fresh vegetables, legumes; also made by intestinal bacteria.
C(Ascorbic Acid)
• 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.
• Scurvy (breakdown of skin, blood vessels, and teeth)• impaired wound healing.
*Vitamin C deficiency- often results secondary to hyperparathy-roidism
• None known• Minimal-possibly urinary calculi, gastrointestinal complaints including diarrhea, nausea and abdominal cramps
• 40-60 mg• 200 - 500 mg
per day
(most
beneficial)
Citrus fruits, green leafy vegetables, tomatoes
Folic Acid(Folacin)
• Nucleic acid metabolism
• Megaloblastic anemia (Pernicious anemia)
None. 400 mcg for
adults Whole-wheat foods, green vegetables, legumes, organ meats, fish, citrus fruits.
Other Vitamins
• Vitamin P (bioflavonoids, citrin)– helps increase strength of capillaries found
in the mesocarp (tasteless, spongy, white layer beneath the rind) of lemon fruit.
• Vitamin F (unsaturated fatty acids)– is important in respiration of vital organs.-helps maintain resilience and lubrication of
cells.-helps regulate blood coagulation.-is essential for normal glandular activity.
• Vitamin B13 (Orotic acid)– is needed for the metabolism of some B-
vitamins
• Vitamin B15 (Pangamic acid)– helps eliminate hypoxia helps promote
CHON metabolism stimulates nervous and glandular system
• Vitamin B17 (Laetrile)– has been linked to cancer prevention
Recommended Dietary Allowance (RDA) for Vitamins
VITAMIN MEN WOMEN
A 0.7mg 0.6mg
B1 1.0mg 0.8mg
B2 1.3mg 1.1mg
Niacin 19mg 15mg
B6 1.4mg 1.2mg
Pantothenic acid
5mg 5mg
VITAMIN MEN WOMEN
Folic acid 0.2mg 0.2mg
Biotin 0.03mg 0.1mg
B12 0.002mg 0.002mg
C 40mg 40mg
D 0.01mg 0.01mg
E 10mg 8mg
K 0.8mg 0.06mg