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Vitamin A
By WLR Dietitian
How much you need each day:
• 600mcg for adult women
• 700mcg for adult men
Why you need it:
Vitamin A is essential for reproduction and growth and
development in children. It’s also necessary for keeping the
skin, hair and eyes healthy and is particularly needed for
vision in dim light. It also keeps the linings of organs such
as the lungs and digestive tract healthy, helping the body to
fight infections. Beta-carotene (which the body uses to make
vitamin A) is also a powerful antioxidant and may help to
protect against diseases such as cancer and heart disease.
Good food sources
There are two forms of vitamin A available to the body –
retinol and beta-carotene, the latter of which is converted
into vitamin A in the body. Retinol is found in foods of
animal origin such as whole milk, cheese, butter, egg yolk,
liver and oily fish. Margarines are also fortified with
vitamin A by law. Beta-carotene is found mainly in dark green
vegetables such as spinach and watercress, and yellow, orange
and red fruits such as carrots, tomatoes, dried apricots,
sweet potatoes and mangoes.
Too little
Low intakes of vitamin A can result in poor
vision, dry skin, impaired reproduction and growth and an
increased susceptibility to infection. In severe cases, it can
lead to xeropthalmia or night blindness, which is often seen
in third world countries. As retinol can be stored in the
liver, a deficiency in this country is rare, although figures
from the most recent National Diet and Nutrition survey show
that 7% of men and 9% of women have vitamin A intakes below
the LRNI. This increases to around one woman in five aged
19-24 years, indicating this group may be the most susceptible
to low intakes.
Top tip:
Reduced-fat dairy products are lower in vitamin A
than full-fat products because the vitamin is removed with the
fat portion of the milk. To get some vitamin A from dairy
products when you’re dieting, go for semi-skimmed rather than
skimmed milk, low-fat rather than fat-free yoghurts and
include small amounts of reduced-fat cheese in your diet.
How to get enough:
Food
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Vitamin A Content (mcg)
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60g boiled carrots
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756
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1/2 mango
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225
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1 boiled egg
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116
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1 tomato
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91
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300ml semi-skimmed milk
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68
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30g reduced-fat Cheddar cheese
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54
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Watch out!
Vitamin A toxicity, which can damage the liver,
bones and eyes, is rare and is usually due to excessive
intakes of vitamin A supplements rather than high intakes from
food. Research also shows a link between high intakes of
vitamin A and reduced bone density, which increases the risk
of hip fracture. Meanwhile, large amounts of vitamin A have
occasionally been linked with congenital abnormalities in
newborn babies, so the Department of Health currently advises
all women planning a pregnancy, or who find they are pregnant,
to avoid taking vitamin A supplements, except on the advice of
their doctor. Because liver can have a high vitamin A content,
pregnant women should also avoid liver and liver products such
as liver sausage or liver pâté.
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