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Vitamin A

It enhances resistance to infection-and so much more

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According to U.S. Department of Agriculture data, 55 percent of Americans do not obtain adequate levels of vitamin A. The vitamin provides many health benefits.


Night blindness. One of the classic signs of vitamin A deficiency is night blindness, characterized by difficulty seeing in the dark or being blinded after exposure to a glaring light (e.g., oncoming headlines). Most serious eye diseases, including cataract, macular degeneration, and glaucoma, are associated with night blindness.

Retinitis Pigmentosa. Doctors commonly recommend 15,000 IU of vitamin A daily for people with retinitis pigmentosa, an inherited disease that accelerates the breakdown of the retina. A recent study found that adding 12 mg of lutein daily further slows vision deterioration in people with this disease.

Cancer protection.Researchers have established the benefits of vitamin A in protection against epithelial cancers, including cancers of the breast and ovary. (Carcinomas are epithelial-related cancers.) In one recent animal study, vitamin A protected against radiation- and estrogen-induced breast cancers. Vitamin A promotes normal differentiation of cells, whereas cancer cells are undifferentiated.

Infection resistance. A 1928 article in the British Medical Journal described vitamin A as the “anti-infective” vitamin-so impressive was its effect on countering bacterial infections, including those of the lungs and urinary tract.

Vitamin A Checklist: How to Get the Best Results

  • Use vitamin A: While beta-carotene has many health benefits, recent research has found that many people do not efficiently convert it to vitamin A. In addition, intestinal bacteria are needed to convert beta-carotene to vitamin A. Unbalanced intestinal bacteria and acid-blocking drugs likely interfere with this conversion.
  • Think zinc: Some research indicates that zinc deficiency may interfere with vitamin A activity, and that vitamin A deficiency can worsen iron-deficiency anemia.
  • Take precautions if pregnant: A 1995 study found that pregnant women who took more than 5,000 IU of vitamin A daily were more likely to deliver babies with cranial-facial birth defects. Although the risk is small, pregnant women should not take more than this amount of vitamin A.
  • Consider taking 10,000 IU of vitamin A daily. This is a typical dosage if you experience night blindness or susceptibility to infections (and are not pregnant).

Go Shopping!

Source Naturals Active A with Beta Carotene 25,000 IU Tablets contain 10,000 IU of vitamin A. and 15,000 IU of beta-carotene in one tablet.
NOW Foods Vitamin A 25,000 IU Softgels provide high-quality vitamin A from fish liver oil.

Nature’s Plus Vitamin A Water Dispersible 10,000 IU Tablets are enriched with lemon grass oil, which is used in the chemical synthesis of vitamin A.

Carlson Vitamin A with Pectin 25,000 IU Softgels provide an emulsified and highly absorbable form of vitamin A.

Nordic Naturals Children’s DHA Strawberry 250 mg Chewable Softgels are made from 100% Arctic cod livers and contain naturally occurring vitamins A and D.