Vitamin A is actually the name for a group nutrients called carotenoids as well as preformed vitamin A. When we think of vitamin A, we generally think of the beta carotene in carrots and how it will help our vision. Vitamin A is so much more than that though!
What does vitamin A do?
Vitamin A is important for vision, as well as the immune system, reproduction, growth and development (1). It’s crucial for many of your organs, like your lungs and heart, to work properly.
Where can you get vitamin A?
There are 2 main categories of vitamin A that we get in our diets: preformed vitamin A and provitamin A carotenoids. Preformed vitamin A does not need to be converted and is found in fish, liver, dairy products, and eggs. Provitamin A carotenoids, however, are converted into vitamin A in the body (like beta carotene). You can find them in fruits, vegetables, and other plants.
The recommended intakes are based on the recommended dietary allowance (RDA). The RDA is estimated to meet the needs of 97-98% of all healthy individuals (2). The recommendations are higher than the amounts to just protect from deficiency. For infants 0-12 months, the recommended amounts are based on the amounts in breastmilk (2).
Retinol Activity Equivalents
Because vitamin A can be taken in preformed vitamin A or provitamin A carotenoids, we use “retinol activity equivalents” (RAE) to standardize our recommendations. All forms of vitamin A are converted into retinol in the body. One mcg RAE = 1 mcg retinol = 2 mcg supplemental beta-carotene = 12 mcg dietary beta-carotene = 24 mcg dietary alpha-carotene or beta-cryptoxanthin (2).
Previously, we used international units for vitamin A, so that may still appear on some labels. 1 IU retinol or supplemental beta-carotene = 0.3 mcg RAE; 1 IU dietary beta-carotene = 0.05 mcg RAE; 1 IU dietary alpha-carotene or beta-cryptoxanthin = 0.025 mcg RAE.
|0-6 months||400 mcg RAE|
|7-12 months||500 mcg RAE|
|1-3 years||300 mcg RAE|
|4-8 years||400 mcg RAE|
What happens if you don’t get enough?
Vitamin A deficiency is not common in the US. There are certain groups, however, who are at increased risk: premature infants, infants/children in developing countries, people with cystic fibrosis, people with Crohn’s disease, ulcerative colitis, or celiac disease.
The most common sign of a deficiency is an eye condition where it’s difficult to see in low light called xerophthalmia. A long term deficiency can increase risk for respiratory diseases and infections. It can also cause anemia.
Can you get too much?
You can definitely get too much preformed vitamin A. This usually happens from supplements, however, not food. It can lead to headaches, nausea, dizziness, muscle aches, problems with coordination, coma, and death (1). Too much preformed vitamin A during pregnancy can lead to birth defects.
High intakes of beta-carotene do not cause the same problems, however. You may notice that your skin turns yellow-orange, but it is otherwise harmless and goes away when you eat less of it. The upper limit is only established for preformed vitamin A.
Vitamin A Rich Foods for Kids
- baked beans
- bell pepper
- black-eyed peas
- breakfast cereals (fortified)
- ice cream
- summer squash
- sweet potato
Krystyn Parks is a Registered Dietitian and Lactation Consultant who specializes in feeding children. She has a Master’s Degree in Nutritional Science from California State University Long Beach. She is an International Board Certified Lactation Consultant and has been registered with the Commission on Dietetic Registration since 2013.