Vitamin C protects the skin from free radicals.

Free radicals are reactive oxygen species naturally produced by the body. However, when cells are faced with a stress, they produce them in excessive amounts. The sources of stress are numerous, the main ones being exposure to UVA, pollution, smoking, and a diet too rich in fats and/or sugars.

Free radicals are particularly unstable molecules due to their single electron. They tend to react with other molecules to form an electron pair, and consequently cause damage to the body's cells, DNA, and proteins. This accelerates ageing and wrinkles appear on the skin's surface.

Vitamin C, or L-ascorbic acid, is a water-soluble vitamin derived from glucose metabolism, present in the body and essential for its proper functioning. When applied topically, it protects the skin from oxidative stress. Its mechanism of action relies on a sequential donation of its electrons to neutralise free radicals. Moreover, several studies have shown that this molecule reduces the production of free radicals such as superoxide radicals, hydroxyl radicals, and simple oxygen molecules. Therefore, it is relevant to apply a vitamin C treatment in the morning to protect one's skin from external aggressions.