Vitamin A is a fat-soluble vitamin found in two different forms in nature.
Vitamin C is a water-soluble vitamin. All animals and plants are capable of producing it, except humans. We therefore have to consume it every day, as our bodies' stocks of Vitamin C are very low.
Principal natural sources of Vitamin C
Plenty of Vitamin C can be found in food.
It is found principally in plants, fruit and fresh vegetables:
Fresh fruit, especially citrus fruit such as oranges, lemons, grapefruit and mandarin; and also red fruit such as strawberries, raspberries, blackcurrants, redcurrants and cherries, to say nothing of mangoes, guavas kiwi fruit, melons and apricots. Of the commonly available fruit, those most rich in Vitamin C are the acerola and kiwi fruit.
Fresh vegetables: green vegetables such as spinach, cress, parsley, green beans and peas; tomatoes, red and green peppers, asparagus, aubergines, turnips, leeks, radishes, onions and artichoke, and various brassicas including cauliflower, Brussels sprouts, cabbage and broccoli.
Potatoes and seeds (but only if they have germinated).
Smaller quantities of Vitamin C can be found in foods of animal origin: offal or giblets (liver), meat (beef and pork), game birds (duck), fish (salmon, tuna and others), crustaceans (oysters) and milk.
Properties of Vitamin C
Vitamin C, also known as ascorbic acid, works at different levels and helps:
- Reduce fatigue.
- Bring about a normal metabolism.
- Strengthen the body's natural defences.
- Protect cells against cellular ageing.
It is known to increase digestive absorption and use of iron, which helps speed red blood cell formation.
Vitamin C favours the formation of collagen, a protein essential for building up and restoring tissues such as skin, cartilage, bones, teeth, muscles and blood vessels.
Recommended Daily Intake
The recommended daily intake varies between 30 and 100 mg per day depending on the population in question, but can reach 1,000 mg (10 times higher) in sporting people and heavy smokers, who produce excessive numbers of free radicals which consume Vitamin C stocks. It is thought that a single cigarette can consume up to 25% of intake.
Apart from these specific cases, the average recommended intake has been set at 80 mg daily.
For whom ?
The following must watch their Vitamin C intake.
- Pregnant and nursing women
- Sporting people
- People whose diet is poor in vitamins
- People under stress
- Babies: cow's milk contains only a quarter of the Vitamin C found in mother's milk.
- Elderly people.