Vitamin A
Vitamin A has two categories: that which comes from an animal sources and that which is plant-based. Vitamin A from animals is known as preformed vitamin A, and is absorbed in the active form as retinol. Retinol comes from a variety of animal sources, most notably milk, whole eggs, cheese, some fish, and liver.
The vitamin A that is plant-based is called
provitamin A cartenoid. This source can be made into
retinol inside the body. One of the more common provitamin A cartenoids is
beta-carotene, which is very efficiently made into retinol.
Great sources of vitamin A from beta carotene include
carrots and carrot juice,
spinach, vegetable soup, cantaloupe, and apricots. Vitamin
A is required for normal
vision, healthy
skin and hair, reproduction/embryonic development and a
healthy
immune system.
How much vitamin A does one need?
The RDA (Recommended Dietary Allowance) for males age 14+ for vitamin A is 900 mcg (micrograms) or 3,000 IU (international units). The RDA for women 14+ is 700 mcg (2,300 IU). Higher levels of vitamin A are recommended for women who are pregnant or lactating: 750 mcg (2,500 IU) minimum for those pregnant and 1200 mcg (4,000 IU) minimum for those in lactation. Food labels will often times not have vitamin A content listed. Instead you will see the % Daily Value (%DV), which indicates the percentage of the nutrient from one serving. For vitamin A the % DV is 5,000 mcg. Some specific examples of high vitamin A (both plant- and animal-based) are:
- Three ounces of cooked beef liver: 27,000 IU (545% DV)
- Three ounces cooked chicken liver: 12,300 IU (245% DV)
- Fortified skim milk, one cup: 500 IU (10% DV)
- Carrot juice, 1/2 cup canned: 22,500 IU (450% DV)
- Frozen spinach, boiled 1/2 cup: 11,400 IU (230% DV)
- Vegetable soup, canned (chunky), 1 cup: 5,820 IU (115% DV)
- Cantaloupe, 1cup, 5,400 IU (110% DV)