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Vitamin
Chenhao Li
Vitamin

A vitamin is an organic compound required
as a vital nutrient in tiny amounts by an
organism . In other words, an organic
chemical compound (or related set of
compounds) is called a vitamin when it
cannot be synthesized in sufficient
quantities by an organism, and must be
obtained from the diet.
List of vitamins
Vitamin A

Vitamin A (or Vitamin A Retinol, retinal, and four
carotenoids including beta carotene ) is a vitamin
that is needed by the retina of the eye in the form
of a specific metabolite , the light-absorbing
molecule retinal , that is necessary for both lowlight ( scotopic vision) and color vision . Vitamin
A also functions in a very different role as an
irreversibly oxidized form of retinol known as
retinoic acid , which is an important hormone-like
growth factor for epithelial and other cells.
Vitamin B

B vitamins are a group of water-soluble
vitamins that play important roles in cell
metabolism .The B vitamins were once
thought to be a single vitamin, referred to as
vitamin B (much as people refer to vitamin
C or vitamin D ).Later research showed that
they are chemically distinct vitamins that
often coexist in the same foods.
Vitamin C

Vitamin C or L- ascorbic acid or L-ascorbate is an
essential nutrient for humans and certain other
animal species.In living organisms ascorbate acts
as an antioxidant by protecting the body against
oxidative stress . It is also a cofactor in at least
eight enzymatic reactions including several
collagen synthesis reactions that, when
dysfunctional, cause the most severe symptoms of
scurvy . In animals these reactions are especially
important in wound-healing and in preventing
bleeding from capillaries.
Vitamin D

Vitamin D is a group of fat-soluble.In
humans, vitamin D is unique because it can
be ingested as cholecalciferol (vitamin D 3 )
or ergocalciferol (vitamin D 2 ) and because
the body can also synthesize it (from
cholesterol) when sun exposure is adequate
(hence its nickname, the "sunshine
vitamin").
vitamin E

Vitamin E refers to a group of eight fat-soluble
compounds that include both tocopherols and
tocotrienols . There are many different forms of
vitamin E, of which γ-tocopherol is the most
common in the North American diet. γTocopherol can be found in corn oil, soybean oil,
margarine and dressings. α-Tocopherol , the most
biologically active form of vitamin E, is the
second most common form of vitamin E in the
North American diet.
Vitamin k

Vitamin K 1 , also known as vitamin K j ,
phylloquinone or phytomenadione (also
called phytonadione), is synthesized by
plants, and is found in highest amounts in
green leafy vegetables because it is directly
involved in photosynthesis.
diseases cause by lack of vitamin

For example, lack of vitamin A can
cause night blindness, lack of vitamin
B1 can cause beriberi, lack of B3 can
cause Pellagra, lack of vitamin C can
cause scurvy, and lack of vitamin D
can cause rickets in children and
osteoporosis.
diseases cause by lack of vitamin

For example, lack of vitamin A can
cause night blindness, lack of vitamin
B1 can cause beriberi, lack of B3 can
cause Pellagra, lack of vitamin C can
cause scurvy, and lack of vitamin D
can cause rickets in children and
osteoporosis.
Vitamin and mineral supplements

If you don't eat a nutritious variety of foods, some
supplements might help you get adequate amounts of
essential nutrients.However, supplements can't take the
place of the variety of foods that are important to a healthy
diet.Scientific evidence shows that some dietary
supplements are beneficial for overall health and for
managing some health conditions.For example, calcium
and vitamin D are important for keeping bones strong and
reducing bone loss; folic acid decreases the risk of certain
birth defects; and omega-3 fatty acids from fish oils might
help some people with heart disease.
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