Vitamin A
Why do you need Vitamin A?
Vitamin A is essential for skin and mucous membranes, required for reproduction (eg cell differentiation).It is necessary for normal vision/eyesight. It also provides immunity and protects against infections.
Vitamin A is found in two forms in our diet:
- retinol(vitamin A) in foods from animal sources, liver, whole milk, butter, cheese, fish (eg salmon)
- carotenoids(ß-carotene is the most common) in foods from plants, eg carrots, tomatoes, dark green leafy vegetables (eg spinach), sweet potatoes, mangos. Beta carotene and some other carotenoids are called vitamin A precursors or provitamins, because they can be converted into vitamin A within the body
How much Vitamin A do you need?
ICMR recommends an intake of 400 mcg/d of retinol for children from 1 to 9 years of age. 600 mcg of retinol is recommended for adolescents from 10 to 17 years of age and for normal adult male and females.
Pregnant and lactating women have higher retinol needs and the RDA for pregnancy is 800 mcg /d and that for lactating women is 950 mcg per day to account for vitamin A secreted in milk.
Vitamin A is a fat soluble vitamin that is utilized in our bodies only if we ingest it in combination with dietary fats. It dissolves in fat before being absorbed in the blood stream to carry out its functions. Excesses of fat soluble vitamins are stored in the liver. Because they are stored, they are not needed every day in the diet.