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 comes from animal products. Beta-carotene is among the second type of vitamin A, which comes from plants.

The American Heart Association recommends obtaining antioxidants, including beta-carotene, by eating a well-balanced diet high in fruits, vegetables, and whole grains rather than from supplements until more is known about the risks and benefits of supplementation.

High doses of antioxidants (including vitamin A) may actually do more harm than good. Vitamin A supplementation alone, or in combination with other antioxidants, is associated with an increased risk of mortality from all causes, according to an analysis of multiple studies.

Why do people take vitamin A?

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 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.

How much vitamin A should you take?

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

Category

Vitamin A: Recommended Dietary Allowance (RDA) in micrograms (mcg) of Retinol Activity Equivalents (RAE)

CHILDREN

1-3 years

300 mcg/day

4-8 years

400 mcg/day

9-13 years

600 mcg/day

FEMALES

14 years and up

700 mcg/day

Pregnant

14-18 years: 750 mcg/day 19 years and over: 770 mcg/day

Breastfeeding

Under 19 years: 1,200 mcg/day

19 years and over: 1,300 mcg/day

MALES

14 years and up

900 mcg/day

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.

Category (Children & Adults)

Tolerable Upper Intake Levels (UL) of Retinol* in micrograms (mcg) of Retinol Activity Equivalents (RAE)

0-3 years

600 mcg/day

4-8 years

900 mcg/day

9-13 years

1,700 mcg/day

14-18 years

2,800 mcg/day

19 years and up

3,000 mcg/day

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

Can you get vitamin A naturally from foods?

Getting enough vitamin A can easily be obtained through a healthy diet.

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 sweet potatoes, carrots, spinach, and apricots.

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