Vitamin A is found in several food sources and adequate amounts are generally provided by a healthy, balanced diet with no need for extra supplementation. Vitamin A is available in both animal and plant foods, as well as in the form of artificial supplements.
Some of the food sources of Vitamin A are described below:
The form of vitamin A absorbed when animal sources are consumed is retinyl palmitate, which gets converted into an alcohol called retinol. Retinol acts as a storage form of vitamin A, which can be converted to and from retinal, the active aldehyde form of the molecule. A particularly rich animal sources of Vitamin A is liver, and consuming liver more than once a week may even cause vitamin A levels to rise too high. High levels of Vitamin A intake can be toxic and lead to a condition called hypervitaminosis A. This is a condition seen in some Eskimos due to consumption of very high amounts of Vitamin A from polar bear liver.
Other examples of animal foods that are rich in vitamin A include:
- Spreads that have been fortified with vitamin A
Plant sources of Vitamin A include orange and yellow fruits and vegetables. The orange/yellow pigment occurs due to the presence of provitamin A carotenoids such as beta-carotene. These compounds need to be converted into vitamin A or retinol in the body before they can be used. Examples of plant sources that contain vitamin A are given below:
- Sweet potatoes
- Spinach and broccoli
- Collard greens
- Cantaloupe melon
The daily amount of vitamin A required by adults is 0.7 mg for men and 0.6 mg for women. Any vitamin A that is not required immediately is stored for future use in bodily functions, meaning vitamin A deficiency is rare in individuals who maintain a healthy, balanced diet.
Reviewed by Sally Robertson, BSc