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A vitamin is an organic compound that your
body requires to grow and develop normally. They are essential
for the normal growth, development and healthy maintenance
of the cells, tissues, and organs that make up a multicellular
organism. Minute amounts of vitamins participate in three
general functions of the body: growth, protection and energy
regulation. They cannot be synthesized in sufficient amounts
nor can they be made in adequate amounts by the body and
must be obtained from our diet. Our bodies need 15 different
vitamins to function properly. They are vitamins A, D, C,
E, K and the B vitamins - thiamine, riboflavin, niacin,
pantothenic acid, biotin, B6, B12 and folic acid. Two additional
substances that have vitamin functions are known as choline
and inositol. Vitamins do not include the essential nutrients
that include minerals, essential fatty acids or essential
amino acids.
Vitamins are classified as either water-soluble
or fat-soluble and primary or secondary. Vitamins are classified
by their biological and chemical activity and have specific
functions. They influence the body as hormones, antioxidants
and/or regulators of cell and tissue growth and function.
The largest number are involved in assisting enzyme reactions
or maintaining a healthy metabolism. Typically, vitamins
originate from plant sources. Vitamins are present in animal
sources of foods only if the animal consumers foodts containing
them, except for vitamins D and C.
Water-Soluble Vitamins
Water-soluble vitamins easily dissolve in
water and are generally excreted from the body - (vitamins
C and B's). Urinary output is a strong indicator of vitamin
consumption. Regularly consuming water-soluble vitamins
is important to avoid a deficiency, as they are not readily
stored in the body. Many types of water-soluble vitamins
are synthesized by bacteria. Excesses are generally excreted
in the urine.
Fat Soluble Vitamins
Fat-soluble vitamins dissolve in fats and
oils, not water, and are absorbed through the intestinal
tract with the help of fats - (A, D, E and K). More likely
to accumulate in the body, fat-soluble vitamins are more
likely to lead to excessive intake than are water-soluble
vitamins.
If optimal amounts of vitamins cannot be consumer
through diet alone, vitamin supplements can be used to ensure
adequate amounts are ingested on a daily basis. Scientific
evidence supports the benefit of dietary supplements and
is well established for certain health conditions.
Vitamin Deficiencies
For the most part, we can get all of the vitamins
our bodies need from the foods we eat, if we choose a balanced
diet from a variety of foods. But many of us don't! Deficiencies
can be due to an inadequate diet; inability to digest food;
inability to absorb vitamins due to damage to the intestine
or to competition with another material such as a drug;
increased physiological need as during pregnancy; growth,
injury, choice of life-style or other environmental factors.
Long-term vitamin deficiencies often lead to serious illness.
A primary deficiency occurs when we don't
get enough of a vitamin in our food. For example, people
who eat a vegetarian diet may not being getting the necessary
amount of B12. A diet deficient in certain vitamins may
result in a compromised immune system or, even worse, a
disease. For instance, low levels of vitamin D may cause
rickets; a vitamin A deficiency may cause night blindness.
A secondary deficiency may be due to an underlying disorder
that prevents or limits the absorption or use of the vitamin,
due to a lifestyle factor, such as smoking, excessive alcohol
consumption, or the use of medications that interfere with
the absorption or use of the vitamin.Well-known human vitamin
deficiencies involve thiamine (beriberi), niacin (pellagra),
vitamin C (scurvy) and vitamin D (rickets).
Vitamin Overdoses
The odds of overdosing on any vitamin from
food is pretty slim, but overdosing from vitamin supplementation
does occur. How much causes symptoms of excessive intake
depends on many factors, including the type of vitamin,
individual tolerance and the length of time for the vitamin
is taken. Because they are stored, excessive consumption
of fat-soluble vitamins can lead to high tissue levels resulting
in toxic side effects, especially for vitamins A and D.
At high enough dosages some vitamins cause side effects
such as achy joints, fatigue, headaches, diarrhea, and vomiting.
When side effects occur, recovery is often as simple as
reducing the dose.
* Please visit our site for a complete
list of Vitamin Supplements >
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