Vitamin A

Name: Vitamin A

Scientific Name:

Intro: Also known as Retinol, this vital nutrient wasn’t even known about until 1913, when scientists discovered it could prevent night blindness. Then, in 1932 it was discovered that beta-carotene, also known as pro-vitamin A, was the precursor to vitamin A. When we consume beta-carotene, vitamin A is produced naturally by enzymes in the digestive tract that break beta-carotene down. The fat-soluble vitamin A is then stored in the liver, where it can remain for long periods of time.

The use of vitamin A supplements supports vision and prevents drying of the cornea. It also plays an important role in maintaining the integrity of epithelial tissues, which consist of the mucous membrane-secreting cells that line all the glands and organs of the body

Nutrient Content:

Benefits:

Supports vision and prevents drying of the cornea.
Plays an important role in maintaining the integrity of epithelial tissues, which consist of the mucous membrane-secreting cells that line all the glands and organs of the body.
Associated with reduced risk of various epithelial-cell cancers (mouth, skin, lungs, bladder, breast, stomach, cervix, etc
Helps the body create effective barriers to infection, thereby boosting overall immunity
Essential for the growth of bones, teeth and soft tissues.
Supplementation in AIDS patients may help increase life expectancy for patients with vitamin A deficiencies.
Lessens risk for cervical dysplasia, easing of heavy menstrual flow, and relief from PMS symptoms
Can lessen the severity of measles and Crohn’s disease

Comments: The Dietary Supplements Information Bureau recommends dosages in the range of 2,000 I.U. to 35,000 I.U. for optimal results, although the most common daily dosage is approximately 5,000 I.U. Since vitamin A is fat soluble, excesses can accumulate in fatty tissues to toxic levels. Consult a doctor if you have been taking high doses of vitamin A over a long period to check for possible symptoms.

Caution: Doses greater than 10,000 IU have caused birth defects, especially during the first seven weeks of pregnancy. Women who could potentially become pregnant should limit their daily vitamin A levels to less than 10,000 IU daily.
This dietary supplement should not be used if you are breast-feeding an infant without first consulting a physician.

Possible Interactions

Bile Acid Sequestrants
These medications decrease the absorption of fat-soluble nutrients such as vitamin A. Supplementation with the affected nutrient(s) may be necessary. These drugs include cholestyramine, colestipol, colesevelam .

Neomycin
Neomycin may change the structure and function of the lining of the digestive tract. These changes may reduce the absorption and increases the elimination of vitamin A from the body. Supplementation with the affected nutrient(s) may be necessary.

Mineral Oil
Mineral oil may decrease the absorption of vitamin A into the body from the digestive tract. Supplementation with the affected nutrient may be necessary.

Vitamin A derivatives
These medications are realted to vitamin A. When they are used with vitamin A there is an increased risk of toxicity. Use with caution. These drugs include isotretinoin, tretinoin, acitretin, alitretinoin .

Orlistat
Orlistat has been reported to decrease vitamin A levels in the body. Supplementation with the affected nutrient may be necessary.

Vitamin E
In an animal study, large oral doses of vitamin A decreased the absorption of vitamin E into the body. Supplementation with the affected nutrient(s) may be necessary.