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Glossary

What does mcg RAE mean for vitamin A?

Written by the Full Measure editorial team, which sells supplements. Approved for publication by the Full Measure owners. Updated .

Drafted with AI assistance from the sources listed below. How we write these

Quick answer

RAE stands for retinol activity equivalents, the unit for vitamin A on labels. It counts how much vitamin A each form gives the body: 1 mcg RAE equals 1 mcg of retinol, 2 mcg of beta-carotene from supplements or 12 mcg of beta-carotene from food. The Daily Value is 900 mcg RAE.1,2

Key facts

  • RAEs exist because retinol and the provitamin A carotenoids differ in activity, and the body converts all of them into retinol.3
  • Alpha-carotene and beta-cryptoxanthin from food count at 24 mcg for each 1 mcg RAE.1
  • The adult RDA is 900 mcg RAE for men and 700 mcg RAE for women.3
  • A label may show how much of its vitamin A is beta-carotene, as in Vitamin A (90% as beta-carotene).4
  • The adult upper limit of 3,000 mcg applies only to preformed vitamin A, such as retinyl palmitate, not to beta-carotene.3

Conversion factors

How many mcg of each form make 1 mcg RAE1,5
Form of vitamin AAmount for 1 mcg RAE
Retinol (preformed vitamin A)1 mcg
Beta-carotene in a supplement, purified in oil2 mcg
Beta-carotene in food12 mcg
Alpha-carotene or beta-cryptoxanthin in food24 mcg

FDA notes that the supplement factor applies only to purified carotenoids in oil. Carotenoids from a food source in a supplement, and carotenoids added to foods, use the dietary factor.5

From IU to RAE

Vitamin A used to be labeled in IU. FDA's example: a supplement with 3,500 IU of vitamin A, all as purified beta-carotene in oil, now lists 1,050 mcg, which is 117% of the Daily Value.5

Older IU figures only convert cleanly when the source is known. One IU of retinol or of supplemental beta-carotene is 0.3 mcg RAE, while one IU of beta-carotene from food is 0.05 mcg RAE.3

Working out the preformed part

Because the upper limit covers only preformed vitamin A, the beta-carotene share on a label matters. NIH's example: a product with 3,000 mcg RAE, 60 percent of it from beta-carotene, provides 1,200 mcg RAE of preformed vitamin A. That is under the adult limit but over the limit for children up to 8.3

Amounts vary widely. NIH reports that 3,000 mcg RAE, or 333% of the Daily Value, is common in vitamin A supplements, while multivitamins often provide 750 to 1,050 mcg RAE.3

Pregnancy, smoking and high doses

Too much preformed vitamin A in pregnancy can cause birth defects. NIH notes that experts advise people who are or might be pregnant, and those who are breastfeeding, not to take more than 3,000 mcg RAE (10,000 IU) a day of vitamin A supplements.3

In two large trials in people who smoked or had smoked, high dose beta-carotene supplements of 20 to 30 mg a day, in one trial taken with retinyl palmitate, raised the risk of lung cancer. If you smoke or used to, ask your doctor before taking beta-carotene.3

Questions people ask

How many IU is 900 mcg RAE?

It depends on the form: 3,000 IU if it comes from retinol or supplemental beta-carotene, and 18,000 IU if it comes from beta-carotene in food.3

Does beta-carotene count toward the vitamin A upper limit?

No. The adult limit of 3,000 mcg covers preformed vitamin A from food and supplements. No limit is set for beta-carotene, though the board advises against beta-carotene supplements for the general population except as a source of vitamin A.3

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Sources

  1. Code of Federal Regulations, Title 21, Section 101.9: Nutrition labeling of food. Legal Information Institute, Cornell Law School (eCFR text). Opened 2026-10-07.
  2. U.S. Food and Drug Administration. Daily Value on the Nutrition and Supplement Facts Labels. Content current as of March 5, 2024. Opened 2026-10-07.
  3. NIH Office of Dietary Supplements. Vitamin A and Carotenoids: Fact Sheet for Health Professionals. Updated March 10, 2025. Opened 2026-10-07.
  4. Code of Federal Regulations, Title 21, Section 101.36: Nutrition labeling of dietary supplements. Legal Information Institute, Cornell Law School (eCFR text). Opened 2026-10-07.
  5. U.S. Food and Drug Administration. Converting Units of Measure for Folate, Niacin, and Vitamins A, D, and E on the Nutrition and Supplement Facts Labels: Guidance for Industry. August 2019. Opened 2026-10-07.

This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.