Brief Definition
Vitamin A belongs to the group of fat soluble vitamins (soluble in fat) is essential for the organism.
This vitamin is present in foods of animal origin as a pre-formed vitamin A and retinol is called while the plant appears as provitamin A, also known as carotenoids that stands out among the beta carotene.
Beta carotene are natural pigments that are found in fruits and vegetables red, orange and yellow, or in dark green vegetables. Beta-carotene is a chemical form required by the body for the formation of vitamin-A.
Approximately 80 and 90% of the retinol esters are absorbed while the beta carotene they do between 40 to 60%. The majority of vitamin A, almost 90% is stored in the liver, the remainder being deposited in the lungs, kidneys and body fat.
Functions of vitamin A and retinol in the body:
* Skeletal system: it is necessary for growth and bone development.
* Cell development: essential for growth, maintenance and repair of mucosal cells, epithelial, skin, vision, nails, hair and tooth enamel.
* Immune system: helps in the prevention of infectious diseases, especially respiratory creating protective barriers against different microorganisms. It stimulates immune functions, including antibody response and the activity of several cells produced by bone marrow involved in defending the body as phagocytes and lymphocytes. Therefore promotes the repair of infected tissues and increases resistance to infection.
* Reproductive System: helps in the normal function of reproduction, contributing to the production of sperm as well as normal female reproductive cycle. Due to its vital role in cell growth, vitamin A helps the changes that occur in the cells and tissues during development of the fetus to develop normally.
* Vision: It is essential for vision, since the Retinol helps improve night vision, preventing certain visual disturbances such as cataracts, glaucoma, vision loss, blindness twilight, also helps fight bacterial infections such as conjunctivitis.
* Antioxidant: Prevents cellular aging and the onset of cancer, since being a natural antioxidant eliminates free radicals and protects DNA from the mutagenic action. (more…)
