Concept about Vitamin | CHAPTER 17 | Basic Science

Concept about Vitamin – Introduction to fundamental concepts of Biological Science including the organization and common characteristics of living matters, cell structures and functions, food production by photosynthesis, harvesting energy, mechanism of cells reproduction, genetics, evolutions, and Human Biology. Introduction to general chemistry including basic concepts about matter, atomic structure, chemical bonds, gases, liquid, and solids, solutions, chemical reactions, acid, bases, and salt;

organic and biochemistry including hydrocarbons and their derivatives, carbohydrates, lipids, proteins, enzymes, vitamins, and minerals, nucleic acids; principles of physics and applications to nursing including gravity and mechanics, pressure, heat and electricity; nuclear chemistry and nuclear physics, effects of radiation on human beings, and protection and disposal. The aim of the course is to acquire knowledge and skills in general biological science, general chemistry and physics.

Concept about Vitamin

Vitamins are organic compounds which are needed in small quantities to sustain life. We need to take vitamins from food because the human body either does not produce enough of them or none at all.

Each organism has different vitamin requirements. For example, vitamin C (ascorbic acid) is necessary for humans but not for dogs, because dogs can produce (synthesize) enough for their own needs, while humans cannot.

Fat-soluble vitamins

Fat-soluble vitamins are stored in the fatty tissues of the body and the liver. Fat-soluble vitamins are easier to store than water-soluble ones and can stay in the body as reserves for days, some o them for months. Fat-soluble vitamins are absorbed through the intestinal tract with the help of fats (lipids). Vitamins A, D, E, and K are fat-soluble.

Water-soluble vitamins

Water-soluble vitamins do not get stored in the body for long they soon get excreted in urin Because of this, water-soluble vitamins need to be replaced more often than fat-soluble ones. Vitamins C and all the B vitamins are water-soluble.

Definition of Vitamin:

Vitamins are vital accessory food factors present in minute quantities in various food substa required by the body in very small quantity and act as catalysts in various body processes is essential for normal growth and development of the body.

[OTHER DEFINITIONS – NICE TO KNOW]

• Vitamins are chemical compounds that the body needs properly in small amounts to help it function.
• Vitamins are organic nutrients that are required in small quantities for a variety of biochemical functions and which generally cannot be synthesized by the body must therefore be supplied by the diet.
• Vitamins are defined as organic compounds, which are required for good health and vitality. It is required for the normal growth. They are required in very small quantity.

Classification of Vitamins:

Vitamins are classified into two broad groups as below-

A. Fat soluble vitamins:

a) Vitamin A or retinol
b) Vitamin D.
c) Vitamin E
d) Vitamin K.

B. Water soluble vitamins:

1. Vitamin B complex:

• Thiamine (vitamin B1)
• Riboflavin (vitamin B2)
• Niacin/Nicotinic acid. (vitamin B3)
• Biotin.
• Pyridoxine (vitamin B6)
• Pantothenic acid(vitamin B5)
• Folic acid.
• Lipoic acid.
• Vitamin B12

1. Ascorbic (vitamin C)

Difference Between Water and Fat Soluble Vitamin:

Difference between vitamins and organic food stuffs:

1. Vitamins do not enter into tissue structure unlike proteins.
2. They do not undergo degradation for providing energy, unlike carbohydrates and lipids.
3. Several vitamins play an important role as “coenzymes” in several metabolic reactions in the body.

Functions of Vitamins:

• Vitamins create the resistance against the diseases.
• Regulate the body metabolism.
• It helps to fat and carbohydrate into energy.
• Vitamins assist in the formation of base of tissue

Concept about Fat Soluble Vitamin

Fat-soluble vitamins are stored in the fatty tissues of the body and the liver. Fat-soluble vitamins A are easier to store than water-soluble ones and can stay in the body as reserves for days, some of them for months.

Fat-soluble vitamins are absorbed through the intestinal tract with the help of fats (lipids). Vitamins A, D, E, and K are fat-soluble.

Vitamin A

Vitamin-A is a fat soluble vitamin which covers both a preformed vitamin, retinal, and a pro- vitamin, beta carotene, some of which is converted to retinal in the intestinal mucosa

Or

Vitamin A is necessary for growth and level it raises the general of resistance against infection. It is therefore called growth promoting and anti-infective vitamin.

Source of Vitamin A:

1. Animal source:

• Liver.
• Mola, dhela (small fish) & other small fishes
• Milk, butter, cheese
• Egg yolk
• Fish liver oil (cod liver oil)

2. Vegetable sources (B-carotene):

• Carrot (richest source of carotene).
• Dark green leafy vegetables such as- sphinach, kachu, sajna, datashak, kalmi, thankune, cabbage etc.
• Some yellow & red fruits (apricots, melon, pumpkin)

3. Fortified foods:

• Vanaspati.
• Margarine
• Milk.

Function of vitamin A:

• It is essential for normal vision. It contributes to the production of retinal pigments, which are needed for vision in dim light.
• It is necessary for maintaining the integrity and the normal functioning of glandular and epithelial tissue, which lines intestinal, respiratory and urinary tracts as well as the skin and eyes.
• It supports growth especially skeletal growth.
• It is anti-infective: there is increased susceptibility to infection and lowered immune response in vitamin A deficiency, and
• It may protect against some epithelial cancers such as bronchial cancers.
• It is essential for the formation of teeth.
• It is essential to maintain normal reproductive function in males.

Effects of vitamin A deficiency:

Two types of effect –

• Ocular
• Extra ocular

Daily requirement of vitamin – A:

Vitamin A is needed because –

1. To keep the eye healthy. Vitamin A keeps the front of the eye (the conjunctiva and cornea) strong, clear, and wet. It helps the eye to see in dim light.

2. To help children to grow properly

3. To prevent infections

4. Vitamin A destroys free radicals and so helps to prevent tissue damage during infection.

Unit of vitamin A

Retinol equivalent (RE)
The conversion can be done in the following way:

• 1 mcg of retinol = 1 mcg of RE
• 1 mcg of beta carotene = 0.167 mcg of RE
• I mcg of other carotenoids = 0.084 of RE

Absorption and storage of vitamin A:

• Vitamin A is absorbed in the small intestine and pass ass along with fate through the lymphatic system into the blood stream, form blood stream liver can store large amount of vitamin A, when fed on diet rich in vitamin A.
• The liver has an enormous capacity for storing vitamin A, mostly in the form of retinol palmitate.
• A well-fed person has sufficient vitamin A reserves to meet his needs for 6 to 9 months or more. In severe protein deficiency, decreased production of retinol-binding protein prevents mobilization of liver retinol reserves.

Symptoms of toxicity of vitamin A:

Excessive intakes of vitamin A are toxic to both children and adults.

1. Hyperirritability.
2. Drying of skin
3. Desquamation of the skin.
4. Loss of hair.
5. Headaches.
6. Enlargement of liver and spleen

Prevention and Control of Night Blindness:

Health promotion:

• Promotion of breast feeding.
• Improvement of environmental health.
• Better feeding of infants & young children.
• Improvement of health service.
• Health education.
• High potency vitamin A for risk group

Specific protection:

• Diet must contain adequate vitamin A
• Immunization.
• Food fortification

Early diagnosis & Treatment:

• Periodic surveillance,
• Early diagnoses & treatment of night blindness.
• Development of programme-
  ✓ Distribution of food.
  ✓ Supplementary feeding
• Treatment of infection & worm infestation

Rehabilitation:

• Blindness rehabilitation service
• Follow up care

Treatment of night blindness:

For children over 1 year and under 6 years old

• Immediately on diagnosis ————–200000 IU. Vit-A -orally
• The following day/next day —————-200000 IU. Vit-A-orally
• After 14 days —— -200000 LU. Vit – A- orally

Measures to Prevent Vitamin A Deficiency:

1. Periodic administration of high-doses of vitamin A (2,00000 IU) is an effective measure of controlling vitamin A deficiency.

2. Adequate treatment and supplementation for mal-nutrition, diarrhea infection and, measles

3. Long term measures including nutrition education such as local sources of the vitamin A or carotenoids, production and consumption of foods rich in vitamin A or pro-vitamin A and fortification of foods with vitamin A

4. Programs to encourage breast feeding increased consumption of dark green leafy egetables, carrot, egg, liver, fish and meal cod liver oil, small fish etc. can be provided when parents can afford

Vitamin D

Vitamin D is a fat soluble vitamin. It is known as calciferol or sunshine vitamin. It is synthesized under the skin when exposed to sunlight. There are three types of vitamin D, they are vitamin D₁, D2, D3.

Sources of vitamin D:

There are two types of sources of vitamin D
1. Natural source: The pro vitamin, 7 dehydrocholesterol, which is normally present in the skin is converted into vitamin D3 by the action of the ultraviolet rays of the sunlight.
2. Animal source: Fish liver oil, egg yolk, milk, butter, ghee.

Daily requirement of vitamin D:

Function of vitamin D:

1. It is required for the formation of healthy bones and teeth. It has a direct action on the ineralization of bones.lt
2. It stimulates the intestinal cells to synthesize calcium- binding protein which helps in alcium absorption.
3. It increases renal tubular re-absorption of phosphate. It has also variable effect on reabsorption of calcium.
4. It permits normal growth.
5. It maintains the concentration of calcium and phosphorus in blood.

Effects of vitamin -D deficiency:

Rickets:
It is a disease of young children (6 months to 2 years) characterized by

• Growth failure
• Bone deformity
• Muscular hypotonia
• Tetany
• Convulsion due to hypocalcemia.

There is an elevated concentration of alkaline phosphatase in the serum.

Osteomalacia in adults:

In adult, vitamin D deficiency may result in osteomalacia which occurs mainly in women, especially during pregnancy and lactation when requirements of vitamin D are increase.

Prevention of vitamin D deficiency:

1. Educating parents to expose their children regularly to sunshine
2. Periodic dosing (prophylaxis) of young children with vitamin D: and
3. Fortification of foods, especially milk.

Treatment and Prevention of Vitamin D Deficiency:

For the treatment of rickets and osteomalacia –
1. About 1000 to 5000 (IU) of vitamin should be administered orally for about a month.
2. Followed by 800 (IU) daily for 6 months.
3. These diseases can be prevented by supplementing the diet with 400 (IU) of vitamin D.

Effects of excess consumption of vitamin D:

1 Nausea.
2. Vomiting
3. Diarrhea.
4. Anorexia.
5. Polyuria.
6. Weight loss.
7. Increase toxicity may result in renal damage and
8. Calcification of soft tissue

Vitamin D is considered as kidney hormone:

It has been proposed that vitamin D should be regarded as a kidney hormone because it does not meet the classic definition of a vitamin, that is, a substance which must be obtained by dietary means because of lack of capacity in the human body to synthesize it. In fact, vitamin D3 is not a dietary requirement at in conditions of adequate sunlight. It can be synthesized in the body in adequate amounts by simple exposure to sunlight even for five minutes per day.

Risk of vitamin D deficiency:

1 Low birth weight babies. LBW babies are born with low stores of vitamin D. If their mother also lacks vitamin D. they get little from breast milk. Mothers may keep them covered and out of the sun because they are worried about them.

2. Babies of mothers who lack vitamin D. There may little vitamin D in breast milk from a mother who lacks vitamin D.

3. Children who live in crowed shanty towns and play mainly inside.

1 Low birth weight babies. LBW babies are born with low stores of vitamin D. If their mother also lacks vitamin D. they get little from breast milk. Mothers may keep them covered and out of the sun because they are worried about them.

2. Babies of mothers who lack vitamin D. There may little vitamin D in breast milk from a mother who lacks vitamin D.

3. Children who live in crowed shanty towns and play mainly inside.

4. Children whose mothers go out to work and leave them inside the house all day.

5. Adolescent girls who do not go outside often and who become pregnant- because their vitamin D needs are particularly high.

6. Women who cover themselves in public and who live in house or apartments with no private garden or courtyard.

7. Old or disabled people who stay indoors all day and who eat a poor diet

Content of vitamin D in some food stuff:

Vitamin E

Tocopherol

• Vitamin E is a fat-soluble vitamin. Chemically it is known as tocopherol. Tocopherol inhibits oxidation hence it is known as antioxidant vitamin
• It is stable to heat and acid. It is lost during processing of fruits vegetables and meats.

Sources of Vitamin E:

Vitamin E is widely distributed in foods. The richest sources of vitamin E are:

Functions of vitamin K:

1. The major function of vitamin K is to promote coagulation of blood after injury thereby preventing hemorrhage.
2. It is involved formation of prothrombin which is the precursor to thrombin-a very important factor in blood clotting.
3. Vitamin K is involved in bone formation and repair
4. In the intestine it also assists in converting glucose to glycogen.

Sources of vitamin K:

Cow’s milk (60 ug/L), human milk (15 ug/L) Sources of vitamin Kı: Fresh dark green vegetables (e.g., spinach. Cauliflower, cabbage) and some fruits. vitamin synthesized by the intestinal bacteria within the body.

Daily requirement of vitamin K:

• Adult: Approximately 0.03 mg/kg
• Premature newborn infant is recommended 0.5 to 1.0 mg of vitamin K

Effects of vitamin K deficiency:

Deficiency of vitamin K is rare because vitamin K is present in many different foods and is produced by intestinal bacteria. However, newborn infants may develop a vitamin K deficiency because they lack intestinal bacteria and therefore do not obtain any vitamin K from this source. People on long-term antibiotic therapy sometimes develop vitamin K deficiency.

Antibiotic (such as penicillin) are drugs used to kill disease-producing bacteria. Some antibiotics kill not only disease producing bacteria but also the vitamin K-producing bacteria in the intestine. In this occurs, a vitamin K deficiency can result, leading to inadequate blood clotting. In this instance, a person bleeds profusely even for minor injuries.

Toxic symptoms of excess intake of vitamin K:

Toxicity does not easily occur with normal dietary intake of this vitamin, but can happen if synthetic compound vitamin KS is taken. High to toxic uptake in the synthetic form can cause flushing and sweating. Jaundice and hemolytic anemia may also develop.

Water Soluble Vitamins

Water-soluble vitamins include B complex and C. These vitamins dissolve in water and are easily destroyed by air, light, and cooking. They are not stored in the body to the extent that fat- soluble vitamins are stored.

Vitamin B1 or thiamine:

Thiamine is a vitamin, also called vitamin B₁. Vitamin B₁ is found in many foods including yeast, cereal grains, beans, nuts, and meat. It is often used in combination with other B vitamins, and found in many vitamin B complex products.

or

Vitamin B1, thiamin, or thiamine, enables the body to use carbohydrates as energy. It is essential for glucose metabolism, and it plays a key role in nerve, muscle, and heart function.

Active form (coenzyrne form): Thiamine pyrophosphate (Tpp),
Chemistry:
Thiamine contains a pyrimidine ring and a thiazole ring held by a methylene bridge.

Sources of Thiamine:

Thiamine is found in many foods, but generally in small quantities.

• Plant sources: whole grain cereals (rice), wheat germ, pulses, oilseeds, nuts, vegetables and fruits.
• Animal source: Liver, fish, meat, egg yolk.

Functions of vitamin B1:

1. Helps in glucose oxidation by acting as coenzyme for oxidative decarboxylation reactions
2. Helps in glucose oxidation through HMP shunt by acting as coenzyme for transketolase
3. Helps to maintain nerve conduction and functioning of nervous system.
4. It is used in the manufacture of hydrochloric acid, and therefore plays apart in digestion.
5. TPP plays an important role in the transmission of nerve impulse. It is believed that TPP is required for acetylcholine synthesis and the ion translocation of neural tissue.

Daily Requirement of Thiamine:

Thiamine is measured in milligrams.

• For adults: 1-1.5 mg/day
• For children: RDA is 0.7-1.2 mg/day.
• Pregnancy and lactation: 2 mg/day

Effects of thiamine deficiency

1. Dry beriberi: Featured by peripheral neuropathy.
The principal manifestations are related to the nervous system. There are

• Anorexia.
• Paraesthesia (i.e. abnormal sensations in the affected limbs).
• Irritability
• Muscular cramps.

2. Wet beriberi: Featured by heart failure and edema. Manifestations arise primarily due to the adverse effects on the cardiovascular system and originate from:

• Wide-spread peripheral vasodilatation
• Retention of sodium and water in the body.
• Failure of the ventricles of the heart due to myocardial weakness

3. Wernick’s encephalopathy: It happens in acute thiamine deficiency and affects central nervous system.

4. Korsakoff psychosis with memory loss: It happens in chronic thiamine deficiency and affects central nervous system.

Prevention of thiamine deficiency:

Thiamine deficiency can be prevented by –

• Beriberi can be eliminated by educating people to eat well balanced, mixed diets containing thiamine-rich foods, e.g. parb-oiled and under milled rice and to stop all alcohol
• Direct supplementation of high-risk groups, e.g. lactating mothers is another approach.
• Beriberi tends to disappear as economic conditions improve and diets become more varied

Vitamin B₂/Riboflavin:

Riboflavin or Vitamin B2 is the yellow enzyme which is heat stable unlike other B Vitamins. Riboflavin in the combined form with proteins form flavo proteins or yellow enzymes.

Chemical structure:
In chemical structure it is a flavin derivative combined with the pentose (d-ribose), a carbohydrate having five carbon atoms.
It was named riboflavin because of the similarity of part of its structure to that of ribose sugar.

Active form (co-enzyme form):
1. FMN (flavin mononucleotide): it is composed of flavin + ribitol + phosphate.
2. FAD (flavin adenine dinucleotide): it is composed of FMN + AMP.

Digestion and Absorption of Riboflavin:

Riboflavin in food is present either in free-state or in combination with a phosphate or with protein and phosphate. This vitamin is absorbed in the upper part of the small intestine and is then phosphorylated in the intestinal wall. In the body it is presented as the coenzyme or flavoproteins.

Functions of Riboflavin:

1. Riboflavin is essential for carbohydrate, fat, and protein metabolism.
2. It is also necessary for tissue maintenance, especially the skin around the mouth, and for healthy eyes.
3. These substances act as coenzymes in many biological reactions primarily in oxidation reduction, and dehydrogenation reaction
4. Release of energy from glucose, fatty acids and amino acids.
5. Conversion of vitamin B6 and folate to active coenzymes.
6. It is essential for the formation of red blood cells
7. It is required for the synthesis of glycogen

Daily requirement of riboflavin:

The recommendation for all including pregnant and lactating women is 0.6 mg per 1000 Kcal.

Sources of riboflavin:

• Animal sources: Milk and milk products, egg, meat and fish in sufficient amount,
• Plant sources: Green leafy vegetables, groundnut and pulses.

Effects of riboflavin deficiency

1. Soreness and burning of the mouth and tongue
2. Lesions at the angles of the mouth called Angular Stomatitis.
3. The inflammation of the tongue called glossitis
4. Dry chapped appearance of the lip with ulcers termed cheilosis.
5. The skin becomes dry and results in seborehoeic dermatitis.
6. Photophobia, lacrimation, burning sensation of the eyes and visual fatigue.
7. Decreased motor co-ordination
8. Normocytic anaemia

Vitamin B3 or niacin:

Niacin is also known as nicotinic acid or nicotinamide. It is a white crystalline compound soluble in water, stable to heat, light, acids and alkalies. In body niacin is converted into niacinamide. Whole cereals, dried yeast, liver, ground nuts, legumes and fish are good sources. Milk, eggs and vegetables are fair sources of the vitamin B3.

B3 Niacin or nicotinic acid is essential for the metabolism of carbohydrate, fat and protein. It is essential for the normal functioning of the skin, intestinal and nervous systems. This vitamin differs from other vitamins of the B-complex groups in that an essential amino acid, Tryptophan serves as its precursor.

Sources of niacin:

• Animal sources: Liver, kidney, meat, poultry’ fish and milk.
• Plant sources: Legumes and groundnut’ whole grain rice’ wheat.

Fig: Foods containing vitamin B3

Functions of B3

1. Niacin functions as a co-enzyme in nearly all the metabolic pathways.
2. Niacin plays a role in tissue respiration (the exchange of oxygen and carbon dioxide in tissue)
3. It is involved in the synthesis and breakdown of fats, and helps maintain healthy skin.
4. It takes part in tissue oxidation.
5. It is essential for the normal functioning of the skin, gastrointestinal and nervous system.

Effects of niacin deficiency:

• Niacin deficiency results in pellagra
• The skin exhibits symmetrical lesions of dark, dry patches with scales.
• There are varying degrees of–
• Irritability.
• Insomnia apathy which may progress-
  – Confusion.
  – Loss of memory
  – Other features of psychotic state.

Prevention of niacin deficiency:
Pellagra is a preventable disease. The preventive measures are:

• A good mixed diet containing milk and/or meat.
• Avoidance of total dependence on maize or sorghum.

Daily requirement of niacin:
The recommended daily allowance is 6.6 mg/1000 kcal of energy intake.

Digestion and absorption of niacin: 
Niacin is easily absorption from the small intestine. Tryptophan, the precursor of niacin, is converted to the vitamin in the body in the presence of pyridoxine.
This amino acid present in large amounts in milk and eggs, prevents niacin deficiency even if the diet does not contain niacin.

Vitamin Bs or Pantothenic acid

Pantothenic acid referred to as the “anti-stress vitamin” is part of the B group vitamins. This vitamin can be produced in the body by the intestinal flora. Pantothenic acid is widely distributed in all foods particularly abundant in that of animal origin, whole grains and legumes’ Human blood normally contains 1g to 35 mg of pantothenic acid per 100 ml. It occurs in small quantities in milk, fruits and vegetables. It is heat-labile.

Functions of Pantothenic acid:

1. Pantothenic acid plays an important role in the secretion of hormones such as cortisone because of the role it plays in supporting the adrenal gland. These hormones assist the metabolism’ help to fight allergies and are beneficial in the maintenance of healthy skin, muscles and nerves.
2. Pantothenic acid is also used in the release of energy as well as the metabolism of fat, protein and carbohydrates.
3. It is used in the synthesis of lipids, neurotransmitters and hemoglobin.
4. It is essential for the oxidation of pyruvic acid.

The visible signs of deficiency include:

1. Nausea.
2. Vomiting
3. Tremor of the outstretched hard.
4. Irritability.

Daily requirement of pantothenic acid:

VITAMIN B6, PYRIDOXAL, PYRIDOXAMINE

Vitamin, B6 or Pyridoxal

Pyridoxine or vitamin B6 exists in three forms:

• Pyridoxine
• Pyridoxal and
• Pyridoxamine.

This vitamin is widely distributed throughout the plant and animal kingdom. Vitamin B6 is water soluble vitamin. The best sources are meat, especially liver, some vegetables and grains with bran.

Deprivation of this vitamin in adults may cause depression, confusion and convulsions.

Sources of pyridoxine:

• Animal sources: Milk, liver, meat, egg yolk, fish.
• Plant sources: Whole grain cereals, carrots, legumes, and vegetable
• Rich sources of pyridoxine are dried yeast, rice polishings, wheat germ and liver.

Functions of pyridoxine:

1. Pyridoxine is required for the balancing of hormonal changes in women as well as assisting the immune system and the growth of new cells.

2. It is essential for the metabolism of proteins, fats and carbohydrates.

3. Pyridoxine might also be of benefit for children with learning difficulties, as well as assisting in the prevention of dandruff, eczema and psoriasis.

4. It assists in the maintenance of serum level of sodium and potassium.

5. It helps to promote red blood cell production.

6. It is involved in the nucleic acids-RNA as well as DNA synthesis.

7. It is linked to cancer immunity and fights the formation of the toxic chemical homocysteine, which is detrimental to the heart muscle.

8. Dietary deficiency of pyroxine is rare and is mostly seen in women taking oral contraceptives and in alcoholics and infants.

Effects of pyridoxine deficiency:
Following condition may develop when pyridoxine is in short supply:

1. Irritability.
2. Nervousness.
3. Insomnia.
4. Anemia.
5. General weakness.
6. Skin changes such as dermatitis
7. Asthma and
8. Allergies.
9. Kidney stones may also form.
10. In children convulsive seizures may be the predominant neurological symptom.

Daily requirement of pyridoxine:

• Adults may need – 2 gm.
• During pregnancy and lactation 22.5 gm/day

VITAMIN B9 / FOLACIN/FOLATE

Vitamin B9 or Folic acid:

The recommended name is folate. Alternative name is Folacin. The usual pharmaceutical preparation is folic acid. Folic acid occurs in food in two forms: free folates and bound folates. It was found effective in curing tropical Macrocytic anaemia in human beings. The pure form of folic acid is pteroylglutamic acid (PGA). The folate acid is heat-labile and cooking partly destroys the vitamins.

Sources of Folate:

The name comes from Latin word folia, means leaf. All leafy vegetables are good dietary sources of folate.

• Animal sources: Liver, meat, dairy products, eggs, milk
• Plant sources: Leafy vegetables, cereals and fruits

Over cooking destroys much of folic acid and this contributes to folate deficiency in man.

Functions of Folate:

1. Folic acid plays a role in the synthesis of the nucleic acids (Which constitute the chromosomes).

2. It is also needed for the normal development of blood cells in the bone marrow.

3. It is also essential for the maturation of red blood cells.

4. Folic acid is required for DNA synthesis and cell growth and energy production as well as the forming of amino acids.

5. Folic acid is crucial for oxygen transport.

6. It is important for healthy cell division and replication.

7. It is also required for protein metabolism and in treating folic acid anemia.

8. This may be effective in treating depression and anxiety.

9. It is required for the synthesis of thiamine.

10. It serves as a mediator in metabolic reactions involving the transfer of one-carbon radicals’

11. It helps to develop of the nervous system of a developing fetus.

Effects of Folate Deficiency:

Folate deficiency commonly found in pregnancy and lactation, where requirements are increased.
It results in-

1. Megaloblastic anaemia
2. Glossitis.
3. Cheilosis.
4. GIT disturbances, e.g., diarrhea, distension and flatulence’
5. Infertility or sterility (due to severe deficiency).
6. May produce abortions or congenital malformations (In early pregnancy).

Daily requirement of folic acid:

Confirmatory Diagnosis of Folic Acid Deficiency:

Though the anemia of folic acid deficiency is indistinguishable from the megaloblastic anaemia of vitamin B12 deficiency, it will respond to the trial therapy with folic acid only. Estimation of serum level (normal range being 6 to 20 ng, i.e. nanogram per 100 ml) will accurately establish the diagnosis. When the level is less than 3 mg per cent it is absolutely sure. When it is found just below 6 mg per cent it is most likely.

CYANOCOBALAMIN

Vitamin B12 or Cyanocobalamin:

Vitamin B12 is a complex organo-metallic compound with a cobalt atom. Its pharmaceutical preparation is cyanocobalamin. It is present in the body tissues as cyanocobalamin, hydroxycobalamin and some other form. It is water soluble and heat stable.

Sources of Vitamin B12:

Vitamin B12 is present only in foods of animal origin. It is not present in foods of vegetable origin.
Important dietary sources of vitamin B12

• Rich sources: Liver – 120mg/100gm
• Good sources: Organ meat, muscle meat, shellfish, eggs, cheese and fish.
• Fair sources: Skimmed milk powder – 3.2 mg/100 gm

Functions of vitamin B12:

1. It stimulates the formation of RBC (Red Blood Corpuscles).
2. It promotes the maturation of RBC.
3. It co-operates with folate in the synthesis of DNA
4. Vitamin B12 has a separate biochemical role, in synthesis of fatty acids in myelin.
5. It stimulates appetite, promote growth.
6. Cobalamin is required in the metabolism of fats, proteins and carbohydrates.
7. It provides protection against allergies, cancer and infection.

Effects of vitamin B12 deficiency:
1. Megaloblastic anaemia (pernicious anaemia).
2. Peripheral neuropathy.
3. Sub-acute combined degeneration of spinal cord.

Daily requirements of B12:

ASCORBIC ACID

Vitamin C or Ascorbic acid:

Vitamin C or ascorbic acid is a water-soluble vitamin. It is the most sensitive of all vitamins. It is easily destroyed by heat, alkalis, drying, storage, cooking in iron vessel, by washing vegetables in water. Vitamin C is absorbed from the intestine. Ascorbic acid is a white crystalline substance”

Functions of vitamin C:

1. One of the principal functions of ascorbic acid is the formation of collagen an abundant protein that forms that intercellular substance in cartilage, bone matrices, dextrin and the muscular epithelium.

2. Vitamin C is important for wound healing and increases the ability to withstand the stress of injury and infection.

3. Ascorbic acid also plays an important role in other hydroxylation reactions.

4. Conversation of Tryptophan to serotonin, an important neurotransmitter and vasoconstrictor, and formation of norepinephrine from tyrosine involves hydroxylation reactions which require ascorbic acid.

5. Conversation of cholesterol to bile acids is another hydroxylation reaction that requires vitamin C.

6. Ascorbic acid is an important antioxidant and thus has a role in the protection of vitamin A and E and the polyunsaturated fatty acids from excessive oxidation.

7. Ascorbic acid enhances iron absorption by reducing ferric iron to ferrous iron across the intestinal mucosa.

8. It may also bind with iron to form a complex which facilitates transfer of iron across the intestinal mucosa.

9. In the circulation ascorbic acid aids in there release of iron from transferring so that it can be incorporated into tissue ferretin.

Sources of vitamin C:

1. Plant sources: All fresh fruits contain vitamin C. Citrus fruits, amloki, Lemon, tomato, guavas, grape fruits, blackberry, straw berry etc.

2. Fresh vegetable: Vegetables especially green leafy vegetables are rich in vitamin C. e.g., cauliflower, cabbage, spinach, cereals etc. Roots and tubers are poor sources of vitamin C”

3. Animal sources: Meat and milk contain very small amounts of vitamin C.

Fig: Sources of vitamin C

Effects of deficiency of vitamin C:

1. Scurvy.
2. Listlessness.
3. Fatigue.
4. Bleeding gums.
5. Fleeting joint pain.
6. Muscle pains”
7. Person has difficulty in breathing.
8. Internal bleeding.
9. Person becomes susceptible to infection.
10. Delayed wound healing occurs.
11. Malformation of bone.
12. Degenerations of muscles.

Daily requirement of vitamin C:

The functions of vitamin C

• Probable disorder: Vitamin C deficiency
• Sources of vitamin C: Please see above
• Functions of vitamin C: Please see above

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• Basic Science | Diploma in Nursing Science and Midwifery