Vitamin
The term ‘vitamin’ was derived in 1911 when an amine thought to prevent beriberi was isolated from rice bran; this essential or vital amine was called a vitamin.
Vitamins are organic substances which are not synthesized within the body, that are essential in small amount for the maintenance of normal metabolic functions. They do not furnish energy and are not utilized as beriberi, rickets, scurvy, etc.
Classification of vitamins
Vitamins are classified on the basis of solubility in two factors--
1. Fat-soluble vitamins
2. Water-soluble vitamins
Fat-soluble vitamins
The vitamins, whose absorption from the intestinal tract is associated with that of lipids, are referred to as fat-soluble vitamins.
Vitamin A, D, E, and K are fat-soluble. Because of impair fat absorption, a deficiency may be induced such as biliary cirrhosis, cholecystitis, etc.
The water soluble vitamins are B and C
Vitamin A
Its other name is retinol.
Source
Common dietary sources of vitamin A are-
1. Animal organs (hearts, kidney, liver)
2. Egg yolk
3. Cream
4. Cheese
5. Butter and milk
6. Green leafy vegetables
7. Carrot
8. Sweet potatoes
Daily requirement
The usual US RDA of vitamin A for-
1. Infants- 1500 unit
2. Children less than four years- 2500 unit
3. Adults and children above four years- 5000 unit
4. Pregnant and lactating women- 8000 unit
Here 1 unit=0.3microgram of retinol.
Function
1. Prevention and cure of xerophthalmia and nyctalopia
2. Prevent hyper keratosis of the skin
3. Inhibit growth retardation
4. Increase body resistance
Deficiency sign
1. Nyctalopia
2. Xerophthalmia
3. Hyperkeratosis
4. Growth retardation
5. Decrease resistance to infection
Vitamin D
It includes ergocalciferol, cholicalciferol, D4, D5 and has antirachitic activity.
Source
1. Butter
2. Cream
3. Liver
4. Milk
5. Cereal etc
Daily requirement
The US RDA for vitamin D is 4000 units per day.
Here 1 unit= 0.025 microgram
Function
1. Helps in absorption of calcium
2. Helps in the calcification of new bones
3. Leads to proper growth of bone and skeleton
Deficiency sign
1. Rickets
2. Osteomalacia
Vitamin E
It is a term that refers to various forms of α-tocopherol including the dextrorotatory isomer and the racemic mixture.
Source
1. Plant oils
2. Green vegetables
3. Whole grains
4. Egg yolks
5. Meats
6. Wheat germ oil etc
Daily requirement
1. Adults and children above four years- 30 units
2. Children under four years- 10 units
3. Infants- 5 units
Here 1 unit= 1 mg of vitamin E
Functions
1. Prevent sterility
2. Exerts antiosidative effect to protect other vitamins in food
3. Essential for normal function of muscle
4. Essential for normal foetal development
5. Necessary for normal reproduction in lower animal
Deficiency sign
1. Sterility
2. Habitual abortion
3. Testicular degeneration
4. Muscular destrophy
Vitamin K
Source
1. Cheese, egg yolk, liver
2. Spinach, cabbage, peas, cereals, soyabean
Daily requirement
- 70μg per day
Functions
1. Helps in the formation of prothrombin
2. Shortens the prothrombin time
3. Prevents hemorrhage
4. Plays an important role in oxidative phosphorylation in the mitochondria
Deficiency sign
1. Hypo-prothrombinemia with resultant prolonged clotting time
2. Uncontrollable hemorrhage in new born
Vitamin B complexes
Thiamin (B1)
Sources:-
1. Vegetable source:- Middle coat of cereal grain, peas, pulse, beans, nuts, unpolished rice.
2. Animal source:- Greatly poor but liver, heart, kidney, egg yolk contain less amount.
Daily requirement:-
| Name | Allowance mg/day |
| Male | 1.5 |
| Female | 1.1 |
| Pregnant | +.4 |
| Lactating women | -.5 |
Functions:-
1. Plays an important role in carbohydrate metabolism.
2. Essential for maintenance of normal apetite and digestion.
3. Essential for normal function of nervous tissue.
Deficiency sign:-
1. Loss of apetite, impaired digestion, severe constipation, gastric atony.
2. Weakness
3. Polyneuritis
4. Cardiac failure.
Riboflavin (B2):-
Sources:-
1. Vegetable source:- Green leafy vegetables, cereal grain, peas, pulse, beans
2. Animal source:-Egg yolk, liver, kidney, milk, meat, heart, muscle.
Daily requirement:-1.8mg (average)
Functions:-
1. acts as co enzyme in tissue oxidation and respiration.
2. It helps in protein, fat and carbohydrate metabolism.
3. Essential for normal growth.
Deficiency sign:-
1. Glositis
2. Angular stomasis
3. Cheilosis
4. Sterol and vulval dermatitis
5. Scrotal and vulval dermatitis
Niacin
Sources:-
1. Vegetable source:- Green leafy vegetables, cereal grain, peas, pulse, beans
2. Animal source:- milk, milk products, fish, liver, meat, egg, yeast.
Daily requirement:-
| Name | Allowance mg/day |
| Male | 18 |
| Female | 15 |
| Pregnant | +2 |
| Lactating women | +5 |
Function:-
1. Prevent pellagra
2. Acts as coenzyme in the form of NAD and NADP.
3. Essential for the normal functioning of the skin, intestinal tract and nervous system.
4. Essential for normal growth.
Deficiency sign:-
1. Stomatitis
2. Glosstis
3. Mental depression
4. Pellagra.
Pantothenic acid (B3):-
Sources:-
1. Vegetable source:- Green leafy vegetables, cereal grain, peas, pulse, beans, whole grain.
2. Animal source:- , liver, meat, egg, yeast, kidney.
Daily requirement:- Unknown but 5-40 mg per day.
Function:-
1. Degradation of fatty acid and other molecules.
2. Convertion of decarboxylated pyruvic acid into acetyl coA.
Deficiency sign:-
1. Retarded growth
2. Failure of reproduction
3. Grawing of hair
4. Dermatitis
5. Fatty liver
6. Haemorrhagic adrenal cortical necrosis.
Pyridoxin (B6):-
Sources:-
1. Vegetable source:- Green leafy vegetables, cereal grain, peas, pulse, beans, whole grain, cabbage, legumes. Animal source:- , liver, meat, egg, yeast, kidney
Daily requirement:-
| Name | Allowance mg/day |
| Male | 2.0 |
| Female | 1.3 |
| Pregnant | +.3 |
| Lactating women | +.5 |
Function:-
1. Acts as coenzyme and involves in trans amination for the synthesis of amino acid.
2. Essential for the metabolism of tryptophan.
Deficiency sign:-
1. Dermatitis around mouth and eye.
2. Anorexia
3. Nausea
4. Vomiting
5. Neuritis
6. Gastro intestinal disorder
7. Convulsion.
Folic acid
Sources-
1. animal source:- liver, kidney, milk, yolk.
2. Vegetable source:- Green leafy vegetables, cereal grain, peas, pulse
Daily requirement: Unknown but 50mg is thought to be enough for person
Function
1. Necessary for maturation of RBC.
2. Necessary for the synthesis of purine and thyumine.
Deficiency sign:-
1. Megaloblastic anamaea.
2. Gastro intestinal disorder.
3. Glossitis
Cyanocobalamine
Sources; liver, eggyolk, kidney, milk, cheese and meat.
Daily requirement: 2 micro gram.
Function:-
1. Essential for maturation and formation of RBC.
2. Necessary for the synthesis of RNA.
Deficiency sign:-
1. Pernicious or megalobklastic anaemaea.
2. Demyelination of the large nerve of the spinal cord specially of the lateral columns
Vitamin C (Ascorbic acid)
Sources
1. Amlaki, orange, lemon, guava, pineapple, papay
2. Cabbage, cauliflower, green peppers, spinach, lettuce, tomato, etc
Daily requirement
1. Male- 40-55mg/day
2. Pregnant- 60-80mg/day
3. Lactating- 80-100mg/day
Functions
1. Maintain normal intracellular material of cartilage, dentine and bone
2. Takes part in wound healing
3. has some metabolic action
4. prevents scurvy
5. protect against infection
6. essential for maturation of RBC
Deficiency sign
1. scurvy
2. anaemia
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