Live Well Vitamins & Lifestyle Guide

Vitamin A (Retinoid)

Vitamin A is key for good vision, a healthy immune system, and cell growth. There are two types of Vitamin A. This entry is primarily about the active form of vitamin A -- retinoids -- that come from animal products. Beta-carotene is among the second type of vitamin A, which comes from plants.

Vitamin A Uses

Topical and oral retinoids are common prescription treatments for acne and other skin conditions, including wrinkles. Oral vitamin A is also used as a treatment for measles and dry eye in people with low levels of vitamin A. Vitamin A is also used for a specific type of leukemia.

Vitamin A has also been studied as a treatment for many other conditions, including cancers, cataracts, and HIV. However, the results are inconclusive. 

Most people get enough vitamin A from their diets. However, a doctor might suggest vitamin A supplements to people who have vitamin A deficiencies. People most likely to have vitamin A deficiency are those with diseases (such as digestive disorders) or very poor diets.

Vitamin A Dose & Instructions for Use

The recommended dietary allowance (RDA) includes the vitamin A you get from both the food you eat and any supplements you take.

The tolerable upper intake levels of a supplement are the highest amount that most people can take safely. Higher doses might be used to treat vitamin A deficiencies. But you should never take more unless a doctor says so.

* There is no upper limit for vitamin A from beta-carotene.

Vitamin A Food Sources

Good food sources of retinoid vitamin A include:

• Eggs
• Whole milk
• Liver
• Fortified skim milk and cereals

Plant sources of vitamin A (from beta-carotene) include carrots, spinach, and apricots.