Categories Menu

Posted in Vitamins |

Vitamin A Benefits

Vitamin A Benefits


Distribution :- Vitamin A is present only in lipids of animal sources and carotenoid, in vegetable ones.

Animal Sources :-

1. Cod-liver oil (400-4000 i.u. per gm)
2. Halibut-liver oil (20,000 i.u. per gm)
3. Milk (2000 i.u. per 600ml).
4. Butter (20-50 i.u. per gm ).
5. Egg (200 i.u.).
6. Fishes are also rich sources.

Vegetable Sources :- Vegetable oils contain very little. Substances which are rich sources of carotene, e.g.

1. Carrots (20 i.u. per gm )
2. Spinach (100 i.u. per gm).
3. Green leaves, yellow fruits such as mangoes tomatoes, etc., are also good sources.

Functions:-
1. Essential for growth.
2. It is a component of rhodopsin, hence essential for night vision (vide `Rhodopsin’).
3. Maintains the integrity and activity of epithelial tissues and glands.
4. Prevents infection (secondary to normal epithelial tissues).
5. It plays some part in protein synthesis.
6. Help in keeping normal fertility.
7. Prevents the condition known as urolithiasis where urinary calculi in the form of calcium phosphate is present.

Deficiency Sign. General Growth :- Failure of growth.
Eye :- Night- blindness( Nyctalopia)

Daily Requirment :- 5,000 i.u. for adults. For growing children and during puberty, lactation and pregnancy – 6,000-8,000 i.u.

FAT-SOLUBLE VITAMINS
VITAMIN A (RETINOL)
Properties :- Soluble in fat-solvents, insoluble in water. Ordinarily it is a viscid colouress oil but by careful fraction ithas also been isolated as pale yellowish needles.

Test :- Give blue colour with antimony trichoride in chloroform. This colour reaction is used as basis for both colorimetric and spectrophotometric methods. The reaction is known as carr price reaction.

Distribution :- Vitamin Ais present only in lipids of animal sources and carotenoid, in vegetable ones.

Animal Source :- 1. Cold- liver oil(400-4000 i.u. per gm)
2. Halibut – liver oil (20,000 i.u. per gm )
3. Milk (2000 i.u. per 600ml)
4. Butter (20-50 i.u.per gm)
5.One egg(200i.u)
6. Fishes are also rich source .

Vegetable Source :- Vegetable oil Contain very little. Which are rich sources of
1. Carotene, e.g. Carrots (20 i.u. per gm )
2. Spinach (100i.u. per gm ).
3. Green leaves,
4. Yellow fruits such as mangoes, tomatoes, etc.are also good sources.

Functions :- 1. Essential for growth .
2. It is a component of rhodopsin, hence essential for night vision.
3. Maintains the integrity and activity of epithelial tissues and glands.
4. prevents infection.
5. It play some part in protein synthesis.
6. Controls the action of the bone cells, so that normal growth and shape of
bone are maintained.
7. Help in keeping normal fertility .
8. Prevent the condition Know as urolithiasis where urinary calculi in the form
of calcium phosphate is present.

Deficiency signs :- Gerneral growth :- Failure of growth.
Eye , Night- blindness. The rhodopsin or visual purple is a chromoprotein containing the carotenoid pigment retinene which is same as vitamin A aldehyde or rentinal as a prosthetic group and a protein opsin.

Daily Requirement :- 5,000 i.u. for adults. For growing children and during puberty, lactation and pregnancy 6,000-8000 i.u..