Vitamins are complex organic compounds of high
biologic activity. Their quantity in foods is low, the role they play being
vital.
In the human body vitamins act as regulators and catalysts. They must be treated
as an indispensable food component, even though some vitamins can be built by
the body itself provided a person eats a healthy, sensible and well-balanced
diet. It is worth mentioning that most vitamins cannot be stored in the body,
vitamins A, D and B12 being an exception (they can be stored for a while in the
liver but their deposits require constant replenishment.) The message is: the
body must get a regular and adequate supply of vitamins. The body wants of them
are dependant on the sex, age, physiological state of a person (pregnancy,
nursing, menstruation etc.) as well as on the climatic conditions, the level of
his/her physical activity, work environment and presence of bad habits. For
example, it is a well-known fact that a daily need of vitamin C of a smoker is
twice as much as that of a non-smoker.
Vitamins entering the body with fresh natural foods possess the strongest and
the most valuable biological action. The question is: Is it healthy to take
in complexes of industrially manufactured vitamins as an addition? Judging
by the opinion of well-experienced dietologists, it is not. But only provided a
person eats a healthy, sensible and well-balanced diet, as we have already
mentioned. These poly-vitamins are chemical analogues of natural vitamins. So,
there is no point in pumping any artificial staff into the body. Besides it is
in question whether these chemicals have been properly tested and absolutely
safe. Nobody can say for sure what can be the impact of the poly-vitamins over
the health in 10 or 20 years. It has been established that overeating of the
artificial vitamin C in the childhood raises the risk of cirrhosis of the liver
30 - 40 years after. Who can secure that future researches won’t find out that
these or those artificial vitamins taken by us now can be responsible for
serious and irreversible changes in the body aggravating its medical condition
and providing the basis for some bad illness. Besides, the price of these poly-vitamins
is undeservedly held up. Trying to reimburse the huge expenses spent on
advertising, the producers are more interested in the quickest sale than in the
long-lasting (ten years or so) researches dealing with the impact of these
vitamin analogues over the body. Buying and taking them in subjects us to risk.
Another thing is hypervitaminosis which is often the result of eating too much
poly-vitamins. At the same time eating a diet rich in any vitamins of natural
origin never causes hypervitaminosis. That is why there is no doubt that the
healthiest and the safest vitamins are those contained in food products.
Vitamins are divided into two big groups:
- soluble in water
- soluble in oils
Water soluble
vitamins are vitamin C and group B
vitamins.
Vitamin C or ascorbic acid is contained in vegetable products. Those of
them richest in vitamin C are sweetbrier, black currants, grapefruit, paprika,
parsley, sorrel, spinach. smaller quantities of vitamin C are found practically
in all vegetables and fruit. Vitamin C provides the main building material for
our skin - the protein of collagen which contributes to its elasticity and
prevents formation of wrinkles.
Shortage of vitamin C exposes a person to the risk of bleeding, decreases the
body resistance to a number of infectious diseases, provokes pains in joints and
causes an abundance of other disturbances in the chain of complex biochemical
reactions processes going on in the body.
Besides, shortage of vitamin C in the diet
interrupts growth of muscles despite anabolic exercising and sufficient and even
surplus amount of protein in the diet.
In the average an adult needs 75 mg of vitamin C a day.
Group B vitamins.
Vitamin B1 or thiamine is contained primarily in liver, nuts, rye
wholemeal bread, eggs, green peas. This vitamin is essential for good
functioning of the nervous system, the liver and the heart. It is involved into
the carbohydrate metabolism and helps to cure skin diseases. The daily need of
vitamin B1 is 2-2,5 mg.
Vitamin B2 or riboflavin is contained mainly in liver, milk, yeast. Many
of us at least once suffered from chaps in the corners of the lips, so called
perleches. Shortage of vitamin B2 is responsible for that. Another indirect
indicators of shortage of this vitamin in the body are dim and easily coming out
hair, scurf. The daily need of vitamin B2 is 2-3 mg.
Vitamin B3 or PP or niacin. Sufficient ingress of this vitamin with food
secures good functioning of the digestive system. This vitamin is involved both
into protein and carbohydrate metabolism. Thanks to it the skin looks healthy
and nice. Sleepiness, the state of depression, dental caries, nasty smell from
the mouth indicate shortage of vitamin B3. Besides, tendency to constipation is
often conditioned by shortage of high-niacin foods in the diet. The vitamin is
contained in the same products as vitamins B1 and B2. But the most valuable
sources of vitamin PP are yeast and bran. The daily need of vitamin B3 is 15 mg.
Vitamin B5 or pantothenic acid plays an important role in the fat
metabolism. It is also needed for building fatty acids and cholesterine. The
sources of vitamin B5 are sea kale, sprouted grain, kidneys, cheese. The daily
need of vitamin B5 is about 10 mg.
Vitamin B6 or pyridoxine. It stimulates functioning of the nervous system
and contributes to the body resistance to various diseases. The main role of the
vitamin is to secure health of the skin, especially of the head skin. The
sources of vitamin B6 are chicken meat, nuts, wholemeal bread, bananas. The
daily need of the vitamin equals to 2 mg.
Vitamin B8 or inosit. The main function of the vitamin is to prevent the
onset of sclerosis. Problems with hair, its premature loss or growing grey, are
indications of shortage of vitamin B8 in the body. Inosit sources are mussels,
nuts, whole meal. The daily need of vitamin B8 is 1 mg.
Vitamin B12 or cyancobalamine. It is needed by the cells of the nervous
tissue and of the bone marrow. Shortage of cyancobalamine is associated with
such a serious medical problem as B12 deficiency anemia, when blood cells are
affected. This illness requires life-long treatment with injections of vitamin
B12. The sources of this vitamin are fat free meat, pluck, fish, mussels. The
daily need of vitamin B12 is 0,005 mg.
Pholate. This acid is needed for building of nuclein acids to form
protein molecules. Pregnant women need pholate most of all. Shortage of it can
aggravate the intrauterine development of the fetus, and affect its nervous
system. big volumes of pholate are contained in green leaf vegetables, avocado,
oranges, beer yeast, strawberry, cabbage. The daily need of pholate is 1,5 mg.
Oil soluble vitamins are A, D, E, K and N.
Vitamin A. There are two kinds of it - retinol and beta-carotin. Retinol
is contained in animal products, such as meat, liver, fish oil, egg yolk, hard
cheese. As for carotin, it is contained in many fruit and vegetables of orange
and red colour. However, colour cannot serve as a reliable indicator of
provitamin A. Biologically active carotine is also found in greenery: dill,
parsley, spinach. But the best sources of carotin are carrots, mangoes, apricots,
papayas, pumpkins, tomatoes. The main function of beta-carotin is to act as an
antioxidant, i.e. to neutralise some harmful oxidation reaction able to start up
tumor processes in the body. Shortage of vitamin A affects the skin, making it
dry and unhealthy greyish. Hair also suffers from vitamin A deficiency, it loses
strength and gets prone to splitting. As for nails, they become fragile and
their growth slows down. To make things still worse, the ability to see in the
dark reduces considerably, the phenomenon being known as night blindness.
Vitamin A is considered to be an agent slackening ageing of the body and helping
to keep the skin smooth and fresh. That is why it is well used in the leading
centres of medical cosmetology. It is worth mentioning once again that vitamin A
is oil soluble, i.e. to activate its valuable properties foods rich in it should
be eaten in combination with vegetable oil, butter, sour cream, mayonnaise. The
daily need of vitamin A is 1 mg.
Group D vitamins. They are involved in the body calcium and phosphorus
metabolism. Therefore, vitamin D is often called an antirachitic factor. Rickets
is a disease arising only in the infantile age, the characteristic features of
it being irreversible changes of skeleton leading to curvature of the legs,
wrong development of the chest and skull bones. Vitamin D prevents the bones of
adults from fractures and malacia. The body is able to build vitamin D itself
under the influence of ultraviolet rays. However, one should be aware that the
possible overdose of vitamin D ( hypervitaminosis) is not safe for the body. The
biggest amounts of vitamin D are contained in the codfish oil, butter, cream,
egg yolk. The daily need of vitamin D is 0,01 mg.
Vitamin E or tocopherol and tocotrienol. They secure normal intake of
oxygen by the body and prevent oxidation processes in it. This vitamin is
essential for metabolic processes, especially going on in the muscles, as well
as for the energy balance maintenance. That is why vitamin E is of vital need
for those who goes in for body building. A number of researches have proven the
ability of tocopherol to prevent premature ageing and destruction of the body
cells. Judging by the outcomes of epidemiological and clinic tests, vitamin E is
also able to reduce the risk of a number of chronic diseases including the
ishemic heart disease, the cataract and some kinds of cancer. Vitamin E is of
vital importance for normal development of pregnancy and the right course of the
birth. In particular, vitamin E prevents misbirth. The best sources of
tocopherol and tocotrienol are young shoots of wheat, as well as sprouts of
other cereals and leaf vegetables. Besides good sources of vitamin E are olive,
maize, sunflower- and lin-seed oils, peanuts. The daily need of vitamin E is
0,0005 mg.
Vitamin K. This vitamin is often called an antihemorrhagic factor, since
it facilitates normal blood coagulability. It can be built in the bowel with the
help of its bacteria. The best sources of vitamin K are soy-bean oil, liver,
nuts, spinach, green salad.
Vitamin N or biotin. It is contained in liver, yeast, milk. Vitamin N
stimulates building of fatty acids and facilitates their processing together
with carbohydrates. Biotin is an essential diet component, because it prevents
dissection of nails and improves their growth. It is also needed to normalise
functions of the skin and of mucous coats and to prevent blackheads and
comedones. The daily need of vitamin N is 0,1 - 0,3
mg.
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