FUNCTIONS:
a. Adaptation to dim light.
b. Promotes growth.
c. Prevents keratinization of the skin and eye.
d. Promotes resistance to bacterial infection.
FOOD SOURCES:
Liver, egg yolk, milk, butter, sweet potatoes, carrots, palm oil, winter squash
DEFICIENCY CONDITION:
a. Night blindness.
b. Xerophthalmia.
c. Hyperkeratosis.
d. Poor growth.
2. VITAMIN D(CALCIFEROLS)
FUNCTIONS:
a. Aids absorption of calcium and phosphorous.
b. Maintains alkaline phosphate for optimum classification.
FOOD SOURCES:
Vitamin fortified milk, egg, cheese, butter, fish.
DEFICIENCY CONDITION:
a. Rickets.
b. Osteomalacia.
3. VITAMIN E(TOCOPHEROLS)
FUNCTIONS:
Prevents oxidation of vitamins A and C and unsaturated fatty acids.
FOOD SOURCES:
Vegetable oil, greens.
DEFICIENCY CONDITION:
a. Neuromuscular problems.
b. Neurological problems.
c. Retinopathy.
d. Impairment of the immune response.
e. Anemia.
4. VITAMIN K(PHYLLO AND FARNOQUINONE)
FUNCTIONS:
Formation of prothromobin and proconvertin for blood clotting.
FOOD SOURCES:
Greens, liver, egg yolk.
DEFICIENCY CONDITION:
Hemorrhage.
5. VITAMIN B1(THIAMIN)
FUNCTIONS:
a. Aids in releasing energy from carbohydrates and fats (as a part of co-enzyme TTP).
b. Forms ribose for DNA and RNA.
FOOD SOURCES:
Meat, whole-grain and enriched cereals, milk, legumes.
DEFICIENCY CONDITION:
Beriberi.
6. VITAMIN B2(RIBOFLAVIN)
FUNCTIONS:
a. Aids in releasing energy (as a part of FMN and FAD).
b. Activates vitamin B6 to convert tryptophan to niacin.
FOOD SOURCES:
Milk, green vegetables, fish, meat, and eggs.
DEFICIENCY CONDITION:
Ariboflavinosis.
7. VITAMIN B3(NIACIN)
FUNCTIONS:
a. Aids in releasing energy (as part of NAD and NADP).
b. Promotes glucosis.
c. Aids in fatty acid synthesis.
FOOD SOURCES:
Meat, poultry, fish, peanut butter, whole-grain and enriched cereals, and greens.
DEFICIENCY CONDITION:
Pellagra.
8. VITAMIN B6(PYRIDOXINE)
FUNCTIONS:
a. Transamination and deamination of amino acids.
b. Aids in porphyrin synthesis (for hemoglobin).
c. Catalyse conversion of tryptophan to niacin.
d. Aids in release of energy from glycogen.
e. Aids in formation of histamine, serotonin, and norepinephrine.
FOOD SOURCES:
Meat, bananas, whole-grains cereals, lima beans, cabbage, potatoes, spinach.
DEFICIENCY CONDITIONS:
a. Anemia.
b. Skin disorders.
c. Nausea.
d. Confusion.
e. Depression.
9. VITAMIN B5(PANTOTHENIC ACID)
FUNCTIONS:
a. Transfers 2 carbon units to release energy (as components of
Co-A).
b. Synthesise porphyrin (hemoglobin formation).
c. Formation of cholestrol and steroids.
FOOD SOURCES:
Organ meats, whole-grain cereals, eggs, lentils, sun-dried tomatoes, whole milk yogurt.
DEFICIENCY CONDITION:
a. Fatigue.
b. Irritation.
c. Insomnia.
d. Stomach pains.
e. Vomiting.
f. Burning feet.
10. VITAMIN B7(BIOTIN)
FUNCTIONS:
a. Releases energy from carbohydrates.
b. Metabolise fatty acids.
c. Deaminates protein.
FOOD SOURCES:
Egg yolk, milk, organ meat, cereals, legumes, nuts.
DEFICIENCY CONDITION:
a. Rashes.
b. Hair loss or total baldness,
c. Anemia.
d. fungal infections.
11. VITAMIN B9(FOLIC ACID, FOLINIC ACID)
FUNCTIONS:
a. Transfers single carbon unit.
b. Synthesis of guanine and adenine, thymine, choline, amino acids, porphyrin (in co-enzyme form).
FOOD SOURCES:
Greens, mushrooms, liver, kidney.
DEFICIENCY CONDITION:
Macrocytic anaemia.
12. VITAMIN B12(COBALAMIN)
FUNCTIONS:
a. Maturation of red blood cells.
b. Aids in providing energy for central nervous system (from carbohydrate metabolism).
c. Formation of single carbon radicals.
d. Converts folacin to active form.
FOOD SOURCES:
Foods of animal origin
DEFICIENCY CONDITION:
Penicious anaemia.
13. VITAMIN C(ASCORBIC ACID)
FUNCTIONS:
a. Formation of collagen.
b. Promotes use of calcium in bones and teeth.
c. Promotes elasticity and strength of capillaries.
d. Conversion of folacin to active form.
FOOD SOURCES:
Citrus fruits, strawberries, papayas, broccoli, cabbage, tomatoes, potatoes, okra.
DEFICIENCY CONDITION:
Scurvy.
REFERENCES
Bengham, S. (1978). Dictionary of Nutrition, A Consumer's Guide to the Facts of Food. Barris & Jenkins, London.
Beryl, R. (1977). Food and Nutrition. Heineman Educational Books, London.
Brownsell, V. I., Griffith, C. J., Eleri, J. (1992). Applied Science Food Studies. Longman Scientific & Technical; UK.
Fox, B. A. and Cameron, A. G. (1989). Nutrition and Health. 5th Ed. Edward Arnold; A Division of Hodder & Stoughton, London.
Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes: Vitamin C, vitamin E, Selenium, and carotenoids. Washington, DC: National Academy press, 2000.
Traber MG, Sies H (1996). "Vitamin E in humans, demand and delivery". Annu. Rev. Nutr.
