Vitamin C: All You Need to Know About This Active Ingredient

Identity Sheet: Vitamin C and Its Stable Derivatives

Fiche d'identité : Vitamine C et ses dérivés stables.

Commonly known as: Ascorbic acid, Vitamin C.

I.N.C.I. list name: Ascorbic Acid, Magnesium Ascorbyl Phosphate, Sodium Ascorbyl Phosphate, Ascorbyl Tetraisopalmitate, Ascorbyl Palmitate, Tetrahexyldecyl

Extraction process: Synthesis from D-glucose by the Reichstein-Grüssner process, combining chemical steps and a microbiological step.

Source: Synthetic.

Botanical name: /

Family: /

Extracted part of the plant: /

Origin, provenance: France.

Chemical properties: Soluble in any aqueous medium; pH < 3.5 (ascorbic acid); pH: 9.0 - 10.0 (stable derivatives of vitamin C) Sparingly soluble in alcohol and polyols; Insoluble in ether and chloroform.

Properties: Emulsion, colloidal solution, true aqueous solution, balm, solid soap, suspension.

Required dosage in cosmetic products: At least 0.2%; Optimal concentration between 5 and 20%; Maximum concentration not regulated.

Function: Antioxidant, pH regulator, masking agent, skin care agent.

Specificities: Antioxidant, lightening, depigmenting, regenerating, unifying, antibacterial, anti-inflammatory, restoring.

Benefits: All skin types, especially dull, pigmented, mature skin prone to imperfections; All hair types, especially dull hair.

Properties

Antibacterial: Reduce the appearance of imperfections (pimples, etc.) by inhibiting the proliferation of bacteria;
Anti-inflammatory: Prevents and reduces redness by inhibiting NF-kB, a transcription factor involved in the immune response and responsible for the activation of a number of pro-inflammatory cytokines;
Antioxidant: Protects intracellular structures from oxidative stress by neutralizing free radicals in the aqueous compartments of the cell by giving up an electron to make them stable and less reactive. In addition, it plays a role in the regeneration of vitamin E, another antioxidant;
Depigmenting, lightening, unifying: Reduces the visibility of brown spots by inhibiting tyrosinase, an enzyme essential in the synthesis of melanin, then interrupting melanogenesis;
Regenerating: Improves the appearance and rigidity of the skin by having the ability to trigger the differentiation of keratinocytes;
Restorative: Provides firmness and suppleness to the skin in order to slow the appearance of signs of aging by stimulating dermal fibroblasts to intensify collagen production, in addition to promoting the synthesis of hydroxyproline, an essential component for the formation of collagen fibers.

Contra-Indications and Precautions

There are no adverse reactions to the use of a vitamin C-based skin care product. On the other hand, it is not recommended to apply this acid on your epidermis if you have a wound in the course of healing to avoid the risks of irritation.

Pure vitamin C must be kept at an acidic pH of around 3.5 in order to avoid oxidation problems. Reducing the pH of a skin care formula can lead to skin sensitivity.

Vitamin C was first discovered in the 18th century. Sailors who sailed long distances and did not eat fruit often suffered from scurvy (a serious disease that can lead to tooth loss). An English naval physician, Dr. James LIND, established a correlation between the consumption of citrus fruits and scurvy. He confirmed this hypothesis with the first clinical trial in human history. In 1928, it was isolated for the first time from lemon juice by Albert SZENT GYÖRGYI, who received a Nobel Prize for this discovery. Scurvy was therefore due to a vitamin C deficiency. It is a water-soluble organic molecule, antioxidant, which neutralizes the action of free radicals generated by exposure to the sun, pollution, smoking etc. responsible for oxidative stress and therefore skin aging. Vitamin C also helps to increase collagen production, restoring firmness and elasticity to the skin. It also inhibits the production of melanin to reduce the appearance of pigmentation spots. To note: Vitamin C is a particularly unstable molecule in aqueous solution. Indeed, in its ionized form, it oxidizes easily and is therefore difficult to formulate, which requires that certain precautions be taken such as the exclusion of oxygen during formulation, oxygen-impervious packaging, a low pH (< 4), a minimal amount of water, and the addition of electrolytes and other antioxidants. This is why in the cosmetic industry, ascorbic acid derivatives are often used (ascorbyl palmitate, ascorbyl stearate, ascorbyl phosphate, magnesium ascorbyl phosphate, ascorbyl glucoside, ascorbyl glucosamine and magnesium ascorbyl PCA...) which are more stable molecules and therefore easier to formulate.