Vitamins
By. Dr. Vidhin Kamble
Sangola College, Sangola
In addition to
carbohydrates, lipid and proteins, inorganic salts and water requires the
presence of organic compounds in diet for the normal growth and good
health. They are organic in nature and
are called as vitamins. Vitamins are
complex organic compounds, whose presence in trace amount in the food is
essential for growth and other physiological activities. Vitamins do not have
any energy value. However they are essential for controlling energy yielding
processes.
The most
important functions of vitamins include.
Physiological processes:
Vitamin A plays a very important role in
visual perception. Vitamin E might ensure fertility in animals. The clotting of
blood is aided by vitamin K. Vitamin C provides immunity against infections and
it may also support processes of growth.
2. Maintenance
of body tissues: The epithelial tissues of the body are maintained by
vitamin A and B2. The growth of bones is ensured by vitamin D. Vitamin E plays
a role in the rejuvenation of tissues. Nourishment to nerve cells is provided
by vitamin B1. The process of maturation of erythrocytes is due to vitamin B12.
3. Metabolic processes:
The process of calcium and phosphorus metabolism happens due to the presence of
vitamin D. Vitamin E remains an antioxidant. Vitamin B1 remains as a co-enzyme
in tissue metabolism and it is found useful in the process of oxidation of
glucose in CNS. Vitamin B2 is essential for carbohydrate metabolism. Niacin
(vitamin B) plays a role as a co-enzyme and is essential for
oxidation-reduction reactions. Normal metabolism of amino acids and fat are due
to vitamin B6. Biotin (vitamin B) serves as a co-enzyme and co-factor in
oxidative metabolism. Vitamin C activates certain intra-cellular enzymes.
Vitamins are
usually divided into two categories on the basis of solubility, which are
1.
Water
soluble vitamins.
2.
Fat
soluble vitamins.
Vitamins A, B, C, D, E and K. are fat soluble present
along with animal fats. Vitamin B and C are water soluble in nature, these are
not stored in to the body and excess amount will be excreted in the urine. Vegetables and fruits containing these
vitamins if washed in water as cut pieces would loose them easily. Vitamin C
and B complex are water-soluble and cannot be stored in our body. Increased
elimination of water by the kidneys will flush out the minerals and vitamins
from our body. So a daily supplement of these vitamins through our diet is
necessary to maintain a proper balance.
Vitamin A, D, E and K, if consumed beyond
required level may cause defects, commonly referred to as vitaminosis. Of the
various vitamins, vitamin D or calciferol on exposure to sunlight can be
synthesised by our body through the lipid compound called ergosterol, found below
our skin. Hence it is known as ‘sunshine vitamin’.
Vitamin A: - It is also
called as Retinol. Vit- A is stored in liver. Fat soluble, soluble in
organic solvents.
Source:-Fish liver oil,
liver, eggs, milk, butter, green vegetables etc.
Deficiency
disorders:
1 Atrophy of lacrymal glands of the eye and
reduction in tear secretion.
2 Corneal epithilium becomes red and dry
(xerosis). It may also become wrinkled and Keratinised (xeropthalmia).
Appearance of Bitot’s spot in the cornea might happen.
3 Cornea may get necrosed and get
infected (keratomalacia).
4 May cause night blindness
(nyctalopia).
Vitamin D :- Also called as Calciferol. Fat soluble.
There are two most important derivatives of calciferols are
ergocalciferol and cholecalciferol having property of preventiving or curing
rickets.
Vitamin D is a
hormone produced by the action of the sun’s ultraviolet rays on the skin.
The primary function of vit. D is to regulate the absorbtion and utilization of
Ca and P which are the chief elements in the framework of the body and makes
the skin breathe.
Sources:-
The main source of
vitamin D is sunlight, so its deficiency is more common in places with
insufficient sunlight.
The other sources of
vitamin D are cod liver oil, egg yolk, fatty fish (like salmon, sardines,
herring, mackerel, tuna), fish and animal liver, milk alfalfa, apples, butter,
cabbage, carrots, , oatmeal, parsley, sweet potatoes, tomatoes, vegetable oils
and whole cereals.
Deficiency disorders:-
Deficiency of
vitamin-D, causes rickets in growing children and osteomalacia in
adults. Defective calcification of bone,
A
deficiency of vitamin D in children results in delayed dentition, faulty bone
formation, rickets, a skeletal (soft bone) deformity in which the joints and
the bones become enlarged, knock-knees and bow legs develop and there is lack
of development at the end of long bones. In adults, vitamin D deficiency
results in osteomalacia, acne, gout, arthritis, myopathy and sometimes near
sightedness. Children suffering from
vitamin D deficiency should be exposed to sunlight after a massage with cod
liver oil. Vitamin D contributes to healthy bone growth and also helps to
resist colds and helps to delay senility. Hypervitaminosis D causes hypercalcaemia,
which leads to symptoms like polyuria, polydipsia, renalcolic, lethargy,
anorexia, nausea, vomiting, dyspepsia, peptic ulceration, weakness, fatigue,
lassitude, headache, constipation, diarrhea, drowsiness and depression.
Vitamin
E
:- Also called as Tocopherol. It
is also called as anti -sterility vitamin. Fat soluble. Resistant to heat (Up to 200 0C).
Tocopherol
is found in α ,β and γ forms, of which α- form is biologically most
potent and can easily absorbed from intestinal tract and stored in to the fat
and muscle. Vitamin E, which is
chemically known as “alpha tocopherol‟, is useful to aid proper
circulation in the body and is related to problems in the muscular tissue,
reproductive and pituitary glands, liver, nerves, heart and circulation. It
protects against the damaging effects of many environmental poisons (pollution)
in the air, water and food.
It
helps prevent formation of scar tissue in burns, sores and thus helps in
post-operative healing. It helps dilate the blood vessels and thus act as an
effective anti-thrombin.
Vitamin E is also said
to improve the fertility, especially in women and it also is said to prolong
aging and so is used as a natural hormone for menopausal females.
Sources:-
Vitamin
E is found naturally in avocados, brown rice, cold-pressed vegetable oils, corn
meal, dry beans, fresh vegetables (like asparagus, broccoli, cabbage, carrot,
green leaves, legumes, parsley, spinach, sweet potatoes and tomatoes). Fruits
(like apples, dried plums and peaches), homemade cottage cheese (paneer), nuts,
oatmeal, organ meats, peanuts, sprouted grains, sunflower seeds, unpasturised
milk,wheat germ and its oil and whole-grain cereals.
Deficiency disorders:-
Rare in human, sterility in experimental animals. A deficiency of vitamin E
results in irregularity in the menstrual cycle; abortion; infertility and a
tendency to bleed easily, from the nose, gums, throat, bladder, etc.
Vitamin K :
Vitamin
K is essential for synthesis by the liver of several factors necessary for the
clotting mechanism of blood and is thus known as a „blood-clotting vitamin‟
and is useful to prevent hemorrhage.
Sources:-
Vitamin
K is synthesized naturally by the bacteria in our intestines. It is also
found in abundance in cabbage, cauliflower, egg yolk, fish oils, grape fruit ,
green leafy vegetables, husk of grains, lemons, liver, oranges, plums,
potatoes, prunes (dried plums), sprouts, strawberries, etc.
Vitamin
K requires bile for its proper absorption and so any obstruction in the bile
duct results in the bile salts not being able to enter the intestines, thus
leading in a poor absorption of vitamin K. So in obstructive jaundice, dietary
vitamin K is not absorbed and so it is important to administer this vitamin
before biliary surgery.
Lack of vitamin
K leads to defect in blood coagulation. In humans, vitamins K deficiency leads
to haemorrhagic manifestations.
Primary
deficiency can occur since the placenta is not able to transfer this vitamin
from the mother‟s blood into the fetus‟ blood and also the newborn baby‟s bowel
has not yet acquired the bacteria and breast milk contains very little of this
vitamin. So this vitamin is given routinely as a supplement to newborn babies
to prevent any haemorrhagic tendency. it is necessary for clotting of blood. It
is necessary for formation of Thrombin which is occur in liver. it is fat soluble and absorption from alimentary tract is
depends upon bile salt.
Vit-K
leads to hemorrhagic disease in chicken due to food deficiency.
Vitamin C :- (Ascorbic acid)
Vitamin
C or Ascorbic acid is useful to combat any respiratory and skin infections,
since it helps to prevent any viral or bacterial infections.
It
is also needed for the absorption of iron and so is useful for the treatment of
anemia.
It
is also useful for healing of wounds and scars, aiding in protein metabolism
and calcification of bones and teeth.
It
is also useful for problems related to the ligaments, arteries, veins, tissues,
bones, teeth, diphtheria, influenza, dysentery, measles, mumps, shingles, fever
blisters, chicken pox, polio, bruises, eyes, complexion, nails, blood, bad
teeth, etc.
This
vitamin is very easily destroyed by heat, increased pH and light and is very
soluble in water and so should be taken in the „raw form‟, since cooking tends
to reduce and eliminate it.
Source:-
Vitamin
C is especially found in fresh raw citrus fruits, like gooseberry (amla),
guavas and oranges. The other sources are alfalfa seeds, apples, asparagus,
avocados, bananas, beans, beets, black currants, broccoli, brussel sprouts,
cabbage, cantaloupe, carrots, cauliflower (raw), collards, cranberry juice,
currants, gooseberries, grapefruit, green peas, guavas, lemons, lettuce, liver,
melons, mustard greens, onions, parsley, plums, potatoes, radishes,
raspberries, red currants, Rhubarb (revandchini), rose hips, spinach (palak),
sprouts, strawberries, tomatoes, turnips and watercress (jalkumb).
Deficiency disorders:-
A
deficiency of this vitamin results in the teeth becoming loose with bleeding
from the gums, diseases like pyorrhea, scurvy, In the absence of this vitamin
the collagen and connective tissue proteins are not synthesised properly to
impaired healing of wounds and capillary haemorrhage, etc.
Its deficiency in the body leads to scurvy, a
diseases charaterised by bleeding gums, loosening and falling out of teeth and
intra muscular haemorrages.
VITAMIN B COMPLEX
Vitamin B complex
consists of the following vitamins –
B1
(thiamine),
|
B2
(riboflavin)
|
,B3
(niacin)
|
B5
(pantothenic acid)
|
B6
(pyridoxine)
|
Folic
acid (folate)
|
B12
(cobalamin)
|
Biotin
|
Choline
|
Inositol
|
PABA(para-aminobenzoic
acid)
|
Although
all are water soluble and considered nontoxic because excesses are excreted
rather than stored, B vitamins are so interrelated that high doses of
individual members of the group can create deficiencies of the others unless a
comprehensive B complex supplement is taken as a daily supplement. Brewer‟s
yeast is an excellent source of the B complex vitamins.
Vitamin B1 or Thiamine
This
vitamin helps to metabolize glucose, fats and carbohydrates and so a deficiency
is likely to affect the nervous system first, since it depends entirely on
glucose for its energy requirements.
Gross deficiency
of vitamins B1, leads to a condition known as beri beri. Beriberi affects
nervous and cardiovascular systems.In children and infants the onset is acute. This vitamin is stored in the liver, heart,
kidney and muscles.
Sources:-
The
rich sources of vitamin B1 are asparagus, brown rice, brussel sprouts, dried
beans, dried plums (prunes), egg yolk, fenugreek (methi) seeds, fish, gingelly
seeds (til), lean meats, legumes, maize, milk and other dairy products, nuts,
oats, organ meats, peas, peanuts with husk, plums, pork, potatoes, raisins,
rice bran, rye, soybeans, sprouted wheat, unpolished rice, wheat germ,
wholemeal wheat flour and bread and yeast. Eating a lot of polished rice,
high-carbohydrate diet, refined starchy and sugary products and heavy alcohol
intake predisposes to or aggravates thiamine deficiency.
Deficiency disorder:
Severe
deficiency of B1 results in a disorder termed as „beriberi‟ (a syndrome
consisting primarily of peripheral neuritis marked by cramps, paraesthesia,
impaired sensation and then sensory and motor paralysis of the limbs and
finally heart failure).
Also a deficiency may result in Wernickels pecacuanha („quiet‟ confusion,
opthalmoplegia, nystagmus and ataxia), Korsakoff‟s psychosis (a memory disorder)
problems with digestion, constipation, nausea, decreased appetite,
irritability, tiredness, oversensitivity, vasodilatation, high cardiac output,
etc.
Vitamin B2 or
Riboflavin
This
vitamin helps in the metabolism of starches and sugar. The natural sources of
vitamin B2 are avocado, beans, broccoli, brussel sprouts, buttermilk, cheese,
curd, currants, eggs, fresh green vegetables, kidney, liver, meat, milk, millet
(bajra), mushrooms, nuts, poultry, spinach (palak), wheatgerm and yogurt.
The
body contains about 30 mg of thiamin and a deficiency starts after about a
month of being on a thiamine-free diet.
A deficiency of vitamin B2 results in growth
failure in children, nerve degradation (especially of the eyes), problems with
the skin, seborrheic dermatitis of the face and extremities, vision,
reproduction, lactation, ulcer of mouth and lips (angular stomatitis), dryness
and cracking of the lips, nostrils, sore throat, loss of weight, insomnia,
anemia, fatigue and joint pains. Loss of appetite and other gastro-intestinal
symptoms, soreness and burning of lips, mouth and tongue. Fissures appear at
edges of the mouth.
Vitamin B3 or
Niacin
Niacin,
also called as Niacinimide, is useful for the proper functioning of liver,
nerves, soft tissues, skin, burning of starches and sugars, gums, circulation
and digestion.
The
sources of vitamin B3 are beans, beef, bran, broccoli, carrots, cheese,
chicken, coffee, corn flour, dry fruits, eggs, fish, fully sprouted grains,
green vegetables, kidney, lemon, liver, milk, peanuts, peas, pork, potatoes,
red meat, soyabean, tomatoes, wholemeal wheat and yeast.
This
vitamin helps in the digestive metabolisms, a deficiency of which results in a condition
termed as “pellagra‟, which has symptoms like erethema and cutaneous
skin eruptions that appear symmetrically over the parts exposed to sunlight.
These skin lesions then proceed to vesiculation and blister formation,
cracking, crusting and finally ulcerative lesions.
The
other symptoms seen in this condition are glossitis (smooth red tongue), nausea
and vomiting, excessive salivary secretion, diarrhea, mental confusion and
dizziness. Toxicity may occur in the form of liver damage with prolonged large
doses.
Its deficiency
leads to pellagra. The principal symptoms of pellagra include mental
changes, (dementia) dermatitis and stomatitis. The tongue becomes smooth,
red and painful.
Vitamin B6 or Pyridoxine
The sources of this vitamin are brewer‟s
yeast, carrots, chicken, eggs, fish, meat, milk and milk products, peas,
soyabean, spinach (palak), sprouted grains, sunflower seeds, walnuts and wheat
germ.
Its
deficiency especially occurs in infants and young children who are fed with
formula milk, i.e. when the milk or cereal is overprocessed resulting in the
depletion of the vitamin. Its deficiency also occurs in people taking drugs
like isoniazid, penicillamine and oral contraceptives.
In human
pyridoxine deficiency causes dermatitis around eyes, nose and behind the ears.
Fissures appear above the lips and angles of the mouth., loss of appetite,
anemia, neuritis, fatigue, listlessness, unclear thinking, seborrhea like
lesions of the face, increased irritability, dizziness and insomnia.
Over-dosage can lead to sensory polyneuropathy.
Vitamin B12 or
Cyanocobalamin
Vitamin
B12 is present mainly in the liver, the kidneys and the heart. This vitamin is
synthesized naturally by the microorganisms in our body. This vitamin is
necessary to form and mature the red blood cells. It is also required for the
maintenance of nervous tissues and to perform several metabolic functions.
Vitamin B12 is found mostly in blue cheese,
clams, dairy products, eggs, herring, kidney, liver, mackerel, milk, seafood
and sprouted grains.
Its deficiency
causes pernicious anaemia, typical sore tongue and several neurological
problems related to the spinal cord.
Deficiency
usually results from an inadequate diet, , gastrectomy, diseases of the
terminal ileum (e.g. crohn‟s disease), tapeworm infection, etc. and takes at least
three years to appear. The deficiency results in megaloblastic anemia and/or
degeneration of the nervous system, decreased growth, skin disorders, asthma,
fatigue, listlessness, paleness, unclear thinking, etc.
Pantothenic Acid
This
vitamin is useful for growth, hair, wrinkles, stress, etc.
The
following are some of the sources of this vitamin – beans, beef, eggs, fresh
vegetables, mother‟s milk, pork, salt-water fish and whole wheat.
A
deficiency of this vitamin leads to degeneration of the nerves, problems with
digestion, constipation, stomach ulcers, anemia, arthritis, water retention
edema, etc.
Folic acid
This
vitamin is found in the red blood cells and is directly involved in DNA and RNA
synthesis.
Folic
acid is present in most of the vegetables and in liver, but can be destroyed by
excessive cooking. The body stores of this vitamin are relatively small,
lasting only for a few weeks.
A
few sources of this vitamin are avocado, barley (jau), beef, chicken, kidneys,
lamb, lentils (masoor), liver, beet root, bran, brewer‟s yeast, brown rice,
brussel sprouts, cauliflower, cheese, dates, dried beans, green leafy
vegetables (especially spinach, asparagus), melon, milk, oranges, organ meats,
peas, potatoes, pork, root vegetables, salmon, tuna, wheat germ and whole
grains.
Deficiency
of this vitamin results in megaloblastic anemia and a few birth defects (like
spina bifida, anencephaly and encephalocele). A deficiency, although rare, is
usually produced by poor intake of vegetables,
pecacu disease, during pregnancy due to the increased demand and due to
certain drugs (like antivitamins such as methotrexate, certain anticonvulsants
and certain oral contraceptive pills).
Choline
This
vitamin is useful for the metabolism of fats and a deficiency results in
problems in liver, kidneys, spleen, gall bladder, (heart trouble), cancer,
fatigue, skin, hardening of arteries, nerves, muscles, diabetes, etc. It is
valuable in all cases of dyspepsia and disorders of the stomach.
It
is found in significant amounts in egg yolks, legumes, meat, milk and whole
grains.
Inositol
This
is a useful vitamin for growth, for problems like early pecacu of hair, hair
loss, utilization of vitamin E, liver, intestines, muscles, brain function and
heart and nerve muscle function.
It
helps prevent hardening of the arteries and is important in lecithin formation
and fat and cholesterol metabolism.
It
is found in fruits, meat, milk, vegetables and whole grains.
Para-Aminobenzoic Acid (PABA)
It is useful for problems in all glands,
thyroid gland, early pecacu of hair, sterility and arthritis and is useful as a
hormone activator.
Biotin
This
is a useful vitamin for mental health, dry skin, poor appetite, muscles, nausea
and mental depression. It is a complex organic acid-containing sulfur, which is
a coenzyme for several carboxylation reactions involving carbon dioxide
fixation.
It
is synthesized by the intestinal bacteria.
It is found in cooked egg yolk, meat, milk, poultry, salt-water fish,
soybeans and whole grains.
