Vitamin A is fat-soluble. It requires fats as well as minerals to be properly
absorbed by your digestive tract.
It can be stored in your body and need not be replenished every day.
It occurs in two forms�preformed vitamin A, called retinol (found only
in foods of animal origin), and provitamin A, known as carotene (provided by
foods of both plant and animal origin).

Vitamin A is measured in USP Units (United States Pharmacopeia), IU
(International Units), and RE (Retinol Equivalents). (See section 168.)
1,000 RE (or 5,000 IU) is the recommended daily dosage for adult males to
prevent deficiency. For females it�s 800 RE (4,000 IU). During pregnancy the new
RDIs/RDAs do not recommend an increase, but for nursing mothers an
additional 500 RE is suggested for the first six months and an additional 400 RE
for the second six months.

There is no formal RDI/RDA for beta-carotene, because it is not (yet) offi-
cially recognized as an essential nutrient. But anywhere from 10,000�15,000
IUs of beta-carotene are needed to meet the RDI/RDA for vitamin A.

WHAT IT CAN DO FOR YOU:

Counteract night blindness, weak eyesight, and aid in the treatment of
many eye disorders. (It permits formation of visual purple in the eye.)
Build resistance to respiratory infections.
Aid in the proper function of the immune system.
Shorten the duration of diseases.
Keep the outer layers of your tissues and organs healthy.
Help in the removal of age spots.
Promote growth, strong bones, healthy skin, hair, teeth, and gums.
Help treat acne, superficial wrinkles, impetigo, boils, carbuncles, and open
ulcers when applied externally.
Aid in the treatment of emphysema and hyperthyroidism.

DEFICIENCY DISEASE:
Xerophthalmia, night blindness.
Deficiency often occurs as a result of chronic fat malabsorption. It�s most
commonly found in children under five years, usually because of insufficient
dietary intake.

BEST NATURAL SOURCE:

Fish liver oil, liver, carrots, dark green and yellow vegetables, eggs, milk and
dairy products, margarine, and yellow fruits. (Note: The color intensity of a
fruit or vegetable is not necessarily a reliable indicator of its beta-carotene
content.)

SUPPLEMENTS:

Usually available in two forms, one derived from natural fish liver oil
and the other water dispersible. Water-dispersible supplements are
either acetate or palmitate and recommended for anyone intolerant to
oil, particularly acne sufferers. 5,000 to 10,000 IU are the most common
daily doses.


(a.lazazaa.com)

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"We can judge the heart of a man by his treatment of animals." ~Immanual Kant~

Great information on Vitamin A. The next topic I'm going to add on my site is on Vitamin A, their benefits, RDA, the different forms, side effects, toxicity, and food sources.

I will add that the animal form of Vitamin A (from eggs, liver, dairy) does not have antioxidant powers like carotenes. Only carotenes are converted to either antioxidants or a form of Vitamin A in the body. About 60% of carotenes are used as antioxidants while the other 40% is converted to Vitamin A as needed by the body. This is a good thing considering that Vitamin A is a fat soluble vitamin. And fat soluble vitamins have a risk of overdose/toxicity if taken in large doses.

There is one caveat to carotenes. That is carotenes, compared to animal forms of Vitamin A, are not as easily abosrbed by the body. Meaning you need to take in more carotenes to have the same effect as animal source Vitamin A. This is actually a good thing b/c it's very, very difficult to overdose on carotenes. And most of the carotenes come from fruits and vegetables (which you should always strive to have more of as well).

I go over this and more on my antioxidants site so stay tuned for more...