Vitamin A is essential for your health, supporting cell growth, immune function, fetal development and vision.
Perhaps one of the best-known functions of vitamin A is its role in vision and eye health.
Retinal, the active form of vitamin A, combines with the protein opsin to form rhodopsin, a molecule necessary for color vision and low-light vision.
It also helps protect and maintain the cornea — the outermost layer of your eye — and the conjunctiva — a thin membrane that covers the surface of your eye and inside of your eyelids.
Additionally, vitamin A helps maintain surface tissues such as your skin, intestines, lungs, bladder and inner ear.
It supports immune function by supporting the growth and distribution of T-cells, a type of white blood cell that protects your body from infection.
What’s more, vitamin A supports healthy skin cells, male and female reproduction and fetal development.
Though vitamin A deficiency is rare in developed countries like the US, it’s common in developing countries, as these populations may have limited access to food sources of preformed vitamin A and provitamin A carotenoids.
Vitamin A deficiency can lead to severe health complications.
According to the WHO, vitamin A deficiency is the leading cause of preventable blindness in children worldwide.
Vitamin A deficiency also increases the severity and risk of dying from infections like measles and diarrhea.
Additionally, vitamin A deficiency raises the risk of anemia and death in pregnant women and negatively impacts the fetus by slowing growth and development.
Less severe symptoms of vitamin A deficiency include skin issues like hyperkeratosis and acne.
Certain groups such as premature infants, people with cystic fibrosis and pregnant or breastfeeding women in developing countries are more at risk of vitamin A deficiency.