Retinol question - Chris???

[Guest guest]

Mother Earth News did a story on the difference in nutritional value

of eggs from pastured hens versus factory-farmed ones, giving

measurements for vitamin A for the eggs of hens raised in different

situations. It's here:

http://www.motherearthnews.com/eggs/chart but it's in micrograms per

100 grams of egg while my cod liver oil is in IU.

How would I figure out how many eggs to eat a day (pastured hens) to

get the equivalent amount of retinol as in cod liver oil?? And I did

notice that the Mother Earth News article measured beta-carotene and

not retinol, which is odd because other sources say retinol comes

from animal sources, so do eggs have both?

Here's what I found about converting mcg to IU (clear as mud):

Vitamin A dosage, intake, recommended daily allowance (RDA)

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Vitamin A is measured in retinol equivalents (RE) which allows the

different forms of vitamin A to be compared. The two primary forms of

vitamin A are retinyl acetate and retinyl palmitate. One retinol

equivalent equals 1 mcg of retinol or 6 mcg of beta carotene. Vitamin

A is also measured in international units (IU) with 1 mcg RE

equivalent to 3.33 IU. The recommended daily allowance (RDA) of

vitamin A is 2,670 International Units (IU) (US National Institute of

Child Health and Human Development), (British Medical Association -

1000 mcg of retinol - equivalent to 6000 mcg of beta-carotene). The

U.S. RDA (recommended daily allowance) for males age 11+ is 1,000

Retinol Equivalents (RE); the RDA for females age 11+ is 800 RE.

Vitamin A is also measured in International Units (IU): 1 RE = 10 IU

for plant products and 1 RE = 3.3 IU for animal products. Since beta-

carotene is converted to vitamin A in the body, the body's

requirement for vitamin A can be supplied entirely by beta-carotene.

Six mg of beta-carotene are considered to be the equivalent of 1 mg

of vitamin A. The American Food and Drug Administration has

established an RDA of 5,000 IU for vitamin A, with a recommendation

that pregnant women maintain their intake around 8,000 IU and that

vitamin A be taken in the form of beta-carotene, which is not

considered toxic. Therapeutic doses have ranged as high as 50,000 IU

for adults. However, any high dose therapy (more than 25,000 IU for

an adult or 10,000 IU for a child) should be closely monitored by a

healthcare professional. Pregnant women, however, should not use

doses of vitamin A greater than the U.S. RDA (5,000 IU/day) without a

physician's recommendation and supervision. Nursing mothers should

avoid doses of vitamin A great than the U.S. RDA (5,000 IU daily),

unless prescribed by a physician.