Vitamin C — Ascorbic Acid
What is vitamin C or ascorbic acid?
Vitamin C, or ascorbic acid, is probably the best-known and most widely used vitamin as a dietary supplement. It is often recommended at the approach of winter or in cases of temporary fatigue, as it is known for its anti-fatigue and toning action (even though it is not a stimulant and does not prevent sleep!), but it has many other beneficial properties. This water-soluble vitamin is not synthesized by the body, which does not know how to store it either, and it must therefore be provided from the diet.
What is its function and what are its benefits?
Vitamin C is first of all a powerful antioxidant: it intervenes both directly, by protecting the cells against the free radicals responsible for cellular aging, and indirectly, by participating in the regeneration of vitamin E, another antioxidant.
One of its most important roles is to stimulate the synthesis of collagen, a protein that is essential for the constitution and strengthening of tissues, skin, bones, teeth, ligaments, gums, etc., thereby contributing to the health of these organs. In addition, vitamin C structures collagen to make it more resistant, via a process called hydroxylation. It also plays an important role in physical energy by being involved in the metabolism of amino acids, especially carnitine.
It contributes to the immune system and protects against infections, and could have an effect on the common cold, even if studies tend to show that it would not have a preventive effect, but simply a reduction of the symptoms and duration, once the cold is established.
It participates in the synthesis of several chemical messengers in the brain, including noradrenaline. It also increases the absorption of iron and plays a role in the formation of red blood cells.
Where to find it?
The main sources of vitamin C in the diet are fruits and vegetables, and in particular: kiwis, citrus fruits (oranges, lemons, mandarins, grapefruits, etc.), red fruits (strawberries, raspberries, blackcurrants, cherries, blueberries, blackberries, etc.), cruciferous vegetables (broccoli, raspberries, blackberries, etc.), and peppers, tomatoes, parsley, mangoes, chestnuts, spinach, leeks, turnips, raw zucchini, green beans, lamb's lettuce, parsnips, etc.
Deficiency and excess
Excesses are rare, as vitamin C is hardly stored, and excesses are excreted in the urine.
Severe deficiency can lead to scurvy, a disease due to a defect in the structure of collagen that causes the fragility of tissues. This manifests itself in bleeding gums, spontaneous hematomas, hemarthrosis (blood effusion in a joint cavity), difficulty in healing and generalized fatigue: this disease, which can be fatal, has practically disappeared in the West. However, cases of deficiency are more common.
Needs may be greater in athletes, pregnant or breastfeeding women, smokers, the elderly, diabetics, people under chronic stress, people who eat little fresh fruit and vegetables, etc.
