Vitamin A
All About Vitamin A
Vitamin A was
given the first letter of the alphabet for a name because it
was the first vitamin to be discovered. It was found that
vitamin A has a large number of uses in the body including
keeping eyes healthy, aiding cell growth and also helping boost
the immune system. However, vitamin A is not only absorbed
directly but it is also created by the body by converting beta
carotene into vitamin A.
Vitamin A itself is found in a number of foods such as eggs,
milk, liver and meat. Beta carotene that the body can convert
into vitamin A is found in many fruits and vegetables,
especially the red, orange and green coloured ones.
The most important point to remember that consuming too much
pure vitamin A can be toxic. It is essential not to exceed the
recommended daily allowance for vitamin A. The actual
recommended allowance of vitamin A varies depending on a
person’s age, sex and other factors.
While the actual amount of vitamin A consumed may be toxic if
the recommended daily allowance is exceeded, there is a far
higher limit to how much beta carotene can be consumed.
Therefore it is advisable to concentrate on obtaining the
greatest amount of beta carotene which the body can then
convert to vitamin A, rather than consuming vast quantities of
pure vitamin A rich foods.
Many people will remember being told that eating lots of
carrots helps you to see in the dark and that is down to the
vitamin A that is produced from the high levels of beta
carotene that are found in the vegetables. Other foods which
have high levels of beta carotene that can be converted to
vitamin A include tomatoes and dark green leafy vegetables,
such as spinach.
Beta carotene is not only used to form vitamin A, but it is
also a powerful antioxidant in itself. None of the beta
carotene that is absorbed is wasted as any excess after
conversion to vitamin A has taken place is used to fight the
harmful free radicals within the body.
Vitamin A also helps fight infections and illnesses by
helping tissues that line various parts of the body, including
the eyes, mouth, nose, throat and lungs, to grow and also to
repair them if they are damaged to prevent infection. Children
also need plenty of vitamin
A to help their bones and teeth to develop
properly.
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