Wednesday, 7 December 2011



Characteristics of vitamins:

*      Very small amounts of vitamins are needed by the human body, and very small amounts are present in foods.
*      Although vitamins are needed in small quantities, the roles they play in the body are enormously important.
*      Vitamins must be obtained through foods, because vitamins either are not made in the body or are not made in sufficient quantities. There is no perfect food that contains all the vitamins in just right amounts.
*      Vitamins have no kcalories.
*      Some vitamins in foods are not the actual vitamin but rather are precursors. The body chemically changes the precursor to the active form of the vitamin.
*      Vitamins are classified according to how soluble they are in fat or water. Fat-soluble vitamins are generally stored in the body, whereas water-soluble vitamins (except B6 and B12) are readily excreted.

1.       Vitamin A
Ø  Functions of vitamin A:
*      Maintains the health of the eye and vision.
*      Promotes healthy surface linings of the lungs, gastrointestinal tract, and urinary tract.
*      Promotes normal reproduction.
*      Promotes growth and development, including bones and teeth.
*      Regulates the immune system so it can fight off infection.
Ø  Recommended intake:
*      Men: 900micrograms RAE
*      Women: 700 micrograms RAE
Upper intake level:
*      3000 microgram/day of preformed vitamin A
Ø  Sources: Preformed; liver, fortified milk, fortified cereals, eggs. Beta-carotene; dark vegetables, deep orange fruits and vegetables.

2.       Vitamin D
Ø  Functions of vitamin D:
*      Maintenance of blood calcium and phosphorus levels so that calcium can build bones and teeth.
*      Bone growth.
Ø  Recommended intake:
AI: 5 micrograms cholecalciferol (31-50 years old), 10 micrograms cholecalciferol (51-70+ years old)
Upper intake level: 50 micrograms cholecalciferol
Ø  Sources: sunshine, fortified milk, fortified cereals, fatty fish, fortified butter and margarine.

3.       Vitamin E
Ø  Functions of vitamin:
*      Antioxidant especially helps red blood cells and cells in lungs and brains.
Ø  Recommended intake:
RDA: 15 mg alpha-tocopherol
Upper intake level: 1000 mg alpha-tocopherol
Ø  Sources: vegetables oils, margarine, shortening, salad dressing, nuts, seeds, leafy green vegetables, whole grains, fortified cereals.

4.       Vitamin K
Functions of vitamin:
*      Blood clotting
*      Healthy bones
Recommended intake:
AI: Men- 120 micrograms, Women- 90 micrograms
Sources: green leafy vegetables, vegetable oils and margarine; made in intestine


Vitamin C
RDA: Men-90mg; Women- 75mg
Upper intake level: 2000mg
*      Collagen formation
*      Wound healing
*      Synthesis of some hormones
*      Healthy immune system
*      Antioxidant
*      Absorption of iron
Citrus fruits, bell peppers, kiwi fruit, strawberries, tomatoes, broccoli, potatoes; fortified juices, drinks and cereals.
RDA: Men-1.2mg; Women- 1.1mg
Upper intake level: none
*      Part of coenzyme in energy metabolism
*      Nerve function
Pork, dry beans, whole-grain etc.
RDA: Men-1.3mg; Women- 1.1mg
Upper intake level: none
*      Part of coenzyme in energy metabolism

Milk, milk products, organ meats, whole grains etc.
RDA: Men-16mg; Women- 14mg
Upper intake level: 35mg
*      Part of coenzyme in energy metabolism

Meat, poultry, fish, organ meats, whole grain etc.
Vitamin B6
RDA: 1.3 mg
Upper intake level: 100mg
*      Part of coenzyme involved in carbohydrate, fat, and protein metabolism
*      Synthesis hemoglobin and some neuro-transmitters
*      Important for immune system
Meat, poultry, fish, potatoes, fruits, vegetables, fortified cereals.
RDA: 400micrograms
Upper intake level: 1000micrograms
*      Part of coenzyme required to make DNA and new cells
*      Amino acids metabolism
Green leafy vegetables, fortified cereals, legumes, orange juices.
Vitamin B12
RDA: 2.4micrograms
Upper intake level: none
*      Part of coenzyme required to make DNA and new cells
*      Conversion of folate into active coenzyme form
*      Normal functioning of nervous system
*      Healthy bones

Animal foods such as meat, poultry, fish, eggs etc.
Pantothenic acid
RDA: 5mg; Upper intake level: none
*      Part of coenzyme in energy metabolism

Fortified cereals, beef, poultry, mushrooms etc.
RDA: 30micrograms
Upper intake level: none
*      Part of coenzyme in energy metabolism and synthesis fat and glycogen

Egg yolks, widespread, made in intestine.
AI: Men-550mg; Women- 425mg
Upper intake level: 3500mg
*      Synthesis neuro-transmitter
*      Synthesis of lecithin found in cell membranes
Widespread, milk, eggs, peanuts.

Reference: Drummond, K. E. & Brefere, L. M. (2010). Nutrition for foodservice and culinary professionals. New Jersey: John Wiley & Sons Inc.

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