Vitamin C or L-ascorbic acid is an essential nutrient for humans and certain other animal species, in which it functions as a vitamin. Ascorbate (an ion of ascorbic acid) is required for a range of essential metabolic reactions in all animals and plants.

Vitamin C, also know as ascorbic acid, is found in a wide variety of fruit and vegetables. Good sources include peppers, broccoli, Brussels sprouts, sweet potatoes, oranges and kiwi fruit.

Vitamin C is a water-soluble vitamin that is necessary for normal growth and development. Water-soluble vitamins dissolve in water. Leftover amounts of the vitamin leave the body through the urine. That means you need a continuous supply of such vitamins in your diet. The pharmacophore of vitamin C is the ascorbate ion. In living organisms, ascorbate is an anti-oxidant, since it protects the body against oxidative stress, and is a cofactor in several vital enzymatic reactions.

Vitamin C is required for the growth and repair of tissues in all parts of your body. It is necessary to form collagen, an important protein used to make skin, scar tissue, tendons, ligaments, and blood vessels. Vitamin C is essential for the healing of wounds, and for the repair and maintenance of cartilage, bones, and teeth.

Vitamin C is one of many antioxidants. Vitamin E and beta-carotene are two other well-known antioxidants. Antioxidants are nutrients that block some of the damage caused by free radicals, which are by-products that result when our bodies transform food into energy.

The build up of these by-products over time is largely responsible for the aging process and can contribute to the development of various health conditions such as cancer, heart disease, and a host of inflammatory conditions like arthritis. Antioxidants also help reduce the damage to the body caused by toxic chemicals and pollutants such as cigarette smoke.

The body does not manufacture vitamin C on its own, nor does it store it. It is therefore important to include plenty of Vitamin C-containing foods in your daily diet.

Scurvy has been known since ancient times. People in many parts of the world assumed it was caused by a lack of fresh plant foods. The British Navy started giving sailors lime juice to prevent scurvy in 1795. Ascorbic acid was finally isolated in 1933 and synthesized in 1934. The uses and recommended daily intake of Vitamin C are matters of on-going debate, with RDI (Recommended Daily Intake) ranging from 45 to 95 mg/day. Proponents of megadosage propose from 200 mg to more than 2000 mg/day. The fraction of Vitamin C in the diet which is absorbed, and the rate at which the excess is eliminated from the body, vary strongly with the dose.

Here are few of the most common questions about Vitamin C answered:

How much do I need?

Vitamin C is a water-soluble vitamin, which means you need it in your diet every day because it can't be stored in the body. You should be able to get all the vitamin C you need from your daily diet. Adults need 40 mg a day.

What does it do?

Vitamin C has a number of important functions. For example it:

•helps protect cells and keeps them healthy

•might help the body absorb iron from food

What happens if I take too much?

It is possible to overdose on Vitamin C and you should take care not to take too much. Taking large amounts of Vitamin C suppliments can cause stomach pain, diarrhoea and flatulence. But these symptoms should disappear once you stop taking them. If you should suffer any side efects, stop taking Vitamin C suppliments for one week and then resume gradually.

What is the current medical advice?

You should be able to get all the vitamin C you need by eating a varied and balanced diet. But if you decide to take vitamin C supplements it's important not to take too much because this could be harmful.

Taking 1000 mg or less of vitamin C supplements a day is unlikely to cause any harm.