Vitamin A

Vitamin A is a fat-soluble vitamin that is important for proper eye sight, growth, cell recognition (cell communication), embryonic development, and immune system. Sources can be both from plants and animal foods.

From fruits and vegetables we get provitamin, the most common being beta-carotene. Beta-carotene is transformed into retinol in the body, which then can execute vitamin A's designated functions.

  From animal foods we get preformed vitamin. These come from all animal sources, such as meat, dairy, poultry, fish, but the concentration is greater in fish oils. These are already in the form of retinol. 

Fun fact:

Beta-carotene is a carotene, which are common red/yellow/orange hued pigments in nature. If too much is consumed for the body to handle, the pigment goes straight into the blood stream. If this happens regularly over time, the skin can get a faint shade of yellow.

Sources:

https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/, https://sml.snl.no/A-vitamin, https://www.hsph.harvard.edu/nutritionsource/vitamin-a/, https://www.britannica.com/story/can-eating-too-many-carrots-make-your-skin-turn-orange,