Vitamin A
Teenagers may have been told vitamin A could help them with troublesome acne. This is right, but it is not all vitamin A does. This vitamin is also important for growth, helping us fight infection and maintaining good eyesight, particularly night vision. That’s why we grew up believing carrots could help us to see in the dark.
How much vitamin A do we need?
|
|
Age
|
RDI*
Vitamin A
(µg /day)
|
|
Infants and toddlers
|
1- 3
|
300
|
|
Children
|
4- 8
|
400
|
|
Boys
|
9-13
|
600
|
|
|
4-18
|
900
|
|
Girls
|
9-13
|
600
|
|
|
14-18
|
700
|
|
Men
|
19-70+
|
700
|
|
Women
|
19-70+
|
900
|
|
Pregnant and breastfeeding women
|
14-18
|
700
|
|
19-50
|
800
|
|
|
Breastfeeding women
|
14-50
|
1100
|
Which foods contain vitamin A?
Vitamin A is a fat-soluble vitamin found in two forms: as retinol (in animal foods) and as carotenoids (in plant sources). The most common of these is beta carotene, which gives the orange colour to carrots. Carotenoids are also found in dark green leafy vegetables (spinach, broccoli) and yellow-orange coloured fruits and vegetables (capsicum, kumara). Retinol is found in liver, milk, cheese and butter.
Vitamin A content of foods
|
|
Vitamin A (µg) |
|
1 slice beef liver
|
17100
|
|
1 cup cheddar cheese
|
273
|
|
1 tablespoon butter
|
148
|
|
1 cup standard milk
|
124
|
|
|
Vitamin A (µg) (as retinol equivalents)(as b-carotene equivalents) |
|
1 carrot
|
1130 (6760)
|
|
1 cup spinach
|
608 (3650)
|
|
1 red capsicum
|
181 (1090)
|
|
1 cup boiled broccoli
|
102 (605)
|
|
1 red kumara
|
19 (110)
|
Vitamin A toxicity
Too much vitamin A (retinol) can be toxic. High levels of vitamin A during pregnancy may increase the risk of birth defects. Women who are pregnant should avoid eating more than 100g of liver a week (as this may be high in vitamin A) and should not take supplements containing vitamin A, including fish oils, unless advised by their doctor.