Vitamin A (Retinol)

Found only in animal sources; particularly fish liver oils (as in cod liver oil), liver, milk, cream, cheese, butter, and eggs.

Vitamin A is essential for healthy eyes and good vision, especially night vision. It is required for the proper growth and maintenance of the skin, bones, and reproductive organs, and helps in building resistance to respiratory infections and boosting immunity. Vitamin A may also protect against cancer, and is useful in the treatment of skin conditions such as acne.

Night blindness or loss of adaptation to the dark; dry eye disease; sty in the eye; increased susceptibility to infection; sinus and bronchial infections; drying out of skin and mucous membranes; loss of taste and smell which leads to loss of appetite; loss of vigor; defective teeth and gums; slowed growth.

7,000 - 10,000 I.U. RDA is 3,000 I.U (900mcg) for men, and 2,300 I.U. (700mcg) for women. The European RDA is 800mcg.

2300mcg (long-term usage), 7500mcg (25,000 I.U.) (short-term usage). People over the age of 65 and those with liver disease are advised to take no more than 15,000IU of Vitamin-A. Vitamin A toxicity can be serious, thus, it is important to ensure that the recommended dose is not exceeded.

Women who are planning to become pregnant or those who are in the first three months of pregnancy should not eat liver, or take vitamin A supplements which contain more than the 800mcg, unless under medical supervision as too much vitamin A can cause birth defects. However, adequate vitamin A is essential during pregnancy. Results of a clinical trial published in 1999 revealed that people who took 25,000 IU of vitamin A each day for approximately four years experienced an 11% increase in triglycerides, a 3% increase in total cholesterol and a 1% decrease in "good" HDL cholesterol, suggesting that people at high risk of developing heart disease should be cautious when thinking about taking supplementary vitamin-A. Meanwhile another study published in 1998 linked a daily intake of just 5,000 I.U. of vitamin-A (the US RDA) with a significant reduction in bone mineral density.

The decrease in bone mineral density was so great that it approximately doubled the risk of hip fracture. Based on these findings, people at high risk of developing osteoporosis - in particular menopausal and postmenopausal women - may benefit from taking betacarotene supplements instead of vitamin-A. Vitamin-A should not be taken by people using the acne medications isotretinoin, resorcinol, topical sulfur, and tazarotene.

SOLUBILITY: Fat soluble