Vitamin Food |
Vitamins
A vitamin is an organic compound
required as a nutrient in tiny amounts by an organism. A compound is called a
vitamin when it cannot be synthesized in sufficient quantities by an organism,
and must be obtained from the diet. Thus, the term is conditional both on the
circumstances and the particular organism. For example, ascorbic acid functions
as vitamin C for some animals but not others, and vitamins D and K are required
in the human diet only in certain circumstances.
All natural vitamins are organic
food substances found only in living things, that is, plants and animals. With
few exceptions, the body cannot manufacture or synthesize vitamins. They must
be supplied by the diet or in dietary supplements. Vitamins are essential to
the normal functioning of our bodies. They are necessary for growth, vitality,
health, general well being, and for the prevention and cure of many health
problems and diseases.
Vitamins are classified by their
biological and chemical activity, not their structure.
Thus, each "vitamin"
may refer to several vitamer compounds that all show the biological activity
associated with a particular vitamin. Such a set of chemicals are grouped under
an alphabetized vitamin "generic descriptor" title, such as
"vitamin A," which includes the compounds retinal, retinol, and many
carotenoids. Vitamers are often inter-converted in the body. The term vitamin
does not include other essential nutrients such as dietary minerals, essential
fatty acids, or essential amino acids, nor does it
encompass the large number of other nutrients that promote health but are
otherwise required less often.
They are vitamins A, C, D, E, K and the B vitamins (thiamine, riboflavin, niacin, pantothenic acid, biotin, vitamin B-6, vitamin B-12 and folate).
You can usually get all your vitamins from the foods you eat.
Your body can also make vitamins D and K. People who eat a vegetarian diet may need to take a vitamin B12 supplement.
Vitamins are classified as either water-soluble or fat soluble.
In humans there are 13 vitamins: 4 fat-soluble (A, D, E and K) and 9 water-soluble (8 B vitamins and vitamin C).
- Water-soluble
Water-soluble vitamins dissolve
easily in water, and in general, are readily excreted from the body, to the
degree that urinary output is a strong predictor of vitamin consumption.
Because they are not readily stored, consistent daily intake is important. Many
types of water-soluble vitamins are synthesized by bacteria.
- Fat-soluble
Fat-soluble vitamins are
absorbed through the intestinal tract with the help of lipids (fats). Because
they are more likely to accumulate in the body, they are more likely to lead to
hypervitaminosis than are water-soluble vitamins. Fat-soluble vitamin
regulation is of particular significance in cystic
fibrosis.
1 comments:
Good info
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