Vitamin C

How many times have you heard it said that taking large amounts of vitamin C will prevent or cure a cold? Science has yet to prove this it true, but vitamin C is important in fighting infections. Vitamin C (also known as ascorbic acid) works as an antioxidant to protect our bodies from damage, is involved in the growth of our bones, tendons, ligaments and skin and increases the absorption of iron from our foods (particularly from vegetarian sources).

How much vitamin C do we need?

	Age	RDI* Vitamin C (mg/day)
Infants and toddlers	1-3	5
Children and adolescents	4-8	6
Men	19-70	45
Men	Over 70	45
Women	19-70	45
Women	Over 70	45
Pregnant and breastfeeding women	14-18	55
Pregnant and breastfeeding women	19-50	60

*Recommended Daily Intake

Who needs more and why?

Smoking causes vitamin C to be used up much more quickly by the body, so smokers should make sure to consume more foods and drinks rich in vitamin C.

Which foods contain vitamin C?

Vitamin C is found in most fruits and vegetables particularly citrus and kiwifruit.

Vitamin C content of foods

	Vitamin C (mg)
1 red capsicum	126
1 grapefruit	94
1 kiwifruit	93
1 cup strawberries	72
1 orange	64
1 boiled kumara	30
1 tomato	30
1 cup boiled silverbeet	27

Vitamin C deficiency

Severe deficiency of vitamin C can lead to scurvy, causing bleeding gums, poor wound healing and bone damage. This is why Captain Cook stocked up on vitamin C-rich limes to stop scurvy running rife amongst his sailors on long sea voyages. It is also why British sailors became known as ‘Limeys’ in North America. This deficiency is rare in New Zealand, although may occur very occasionally in older people.

Vitamin C supplements

Vitamin C supplements are usually unnecessary as it is easy to obtain enough from common foods – see the table above. As vitamin C is a water-soluble vitamin, any excess will be excreted in your urine. While vitamin C toxicity is very rare, taking supplements containing more than 2,000 mg per day can lead to stomach upsets and diarrohea.