Vitamin A Requirements

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Vitamin A is most commonly measured in international units (IU).
Vitamin A requirements vary depending on age, gender, and if pregnant or nursing.

Vitamin A most commonly is measured in international units (IU), a measure of biological activity. It also may be measured in retinol equivalents (RE) or in milligrams (mg). A retinol equivalent indicates the amount of retinol to which a substance (such as beta-carotene) can be converted in the body. One RE of vitamin A equals 3.3 IU. 1.5 mg of vitamin A equals 5000 IU.

Daily values (DV) are nutrient intake recommendations from the U.S. Institute of Medicine and are based on outdated recommendations from 1968. Most vitamin supplement labels continue to display daily values. The latest recommendations from the Food and Nutrition Board of the National Academy of Sciences are for dietary reference intake (DRI). They include the recommended daily allowance (RDA) and the adequate intake (AI). AI is used for nutrients with insufficient scientific data to calculate an RDA.

The Recommended Daily Allowance (RDA) for vitamin A, including the combination of diet and supplemental vitamin A, varies for different individuals and is dependant on gender and age:

•	Adult Men	3000 IU
•	Adult Women	2330 IU
•	Pregnant Women	2500-2565 IU
•	Nursing Women	3960-4300 IU
•	Children	1240-2310 IU

Adequate intake for infants:

	•	Age 0 - 6 Months	1320 IU
	•	Age 6 - 12 Months	1650 IU