Which skincare products contain lactic acid?

Lactic acid is a organic acid that belongs to the family of alpha-hydroxy acids (A.H.A.). This active ingredient is highly valued because compared to glycolic acid, another A.H.A., lactic acid is gentler and better tolerated. Indeed, the weight of lactic acid being 90.08 g/mol, it is higher than that of glycolic acid which is 76.05 g/mol. Thus, it penetrates the epidermis less deeply and acts in a superficial manner.

When applied topically, lactic acid offers numerous benefits:

• It possesses keratolytic properties meaning that it eliminates dead cells on the surface of the epidermis which clog the pores and dull the complexion. It dissolves intercellular bonds, thus stimulating cellular renewal. As such, it revives dull complexions and prevents the appearance of blackheads. Moreover, studies have shown that the application of lactic acid contributes to a reduction in inflammatory spots.

  Please note: In vivo studies have demonstrated that the application of 12% lactic acid for 3 months results in a reduction of wrinkles, an improvement in skin elasticity, and an increase in dermal cells.

• It effectively hydrates the epidermis. Indeed, researchers have shown that lactic acid improves the skin's Natural Moisturising Factor (NMF).

  Please note: the NMF or Natural Moisturising Factor accounts for 30% of the total dry weight of the stratum corneum. It is composed of amino acids, their derivatives, and extracellular compounds such as lactic acid or urea. Its hygroscopic properties allow it to capture and retain water in the stratum corneum, thus maintaining good skin hydration.

• It helps to fade pigmentation spots. Lactic acid inhibits the activity of enzymes involved in the process of melanogenesis (the mechanism responsible for the production of melanin): the tyrosinases. The results of studies prove that the topical application of lactic acid significantly reduces pigmentation spots. However, these studies were conducted on a peel with 82% lactic acid (this is above the concentration allowed in cosmetics, which is 10%). The use of high-dose lactic acid requires the intervention of a healthcare professional.

Although the merits of lactic acid are primarily praised for the skin, it also offers benefits for the hair :

• It possesses a dandruff-fighting action. Dandruff is a problem that affects many people. Indeed, this phenomenon is caused by an overly rapid cellular renewal. The skin cells, not mature enough to naturally eliminate themselves, remain clumped together. The use of kerato-reductive agents such as lactic acid allows for effective dandruff removal. Indeed, thanks to its keratolytic properties, it facilitates the elimination of dandruff.

• If your scalp is dry, this could be due to a malfunction of your hydrolipidic film. Lactic acid has hygroscopic properties that allow it toprevent insensible water loss and to strengthen the corneal layer which is responsible for skin protection.

It's important to note : the scalp is simply an extension of the facial skin! The only difference is the significant presence of hair follicles.

Lactic acid thus helps to purify the scalp.

Please note : Lactic acid is also used as a pH regulator. It serves to acidify hair care products, particularly conditioning and foaming products.

Due to the benefits previously mentioned, lactic acid is present in many cosmetic products. It comes in various forms such as lotions, serums, creams, cleansers, shower gels, masks, and even tonics. Furthermore, it is also used in cosmetic formulation as it is a pH regulator.

Typology has developed two treatments based on lactic acid: the gentle peeling serum and the peeling mask.

• Highly concentrated, (10% lactic acid), the gentle peeling serum provides your skin with a gentle exfoliation due to its superficial action. By ridding the skin of its dead cells, it revives the complexion's radiance and fights against imperfections. The skin is smooth and glowing. Moreover, it contains an antioxidant, theacerola extract , which combats the free radicals responsible for a dull complexion. Our serum is suitable for all skin types (oily, dry, and combination skin). It is also suitable for sensitive skin as unlike glycolic acid, it is non-irritating.

• Composed of an exfoliating complex based on four A.H.A.s and a P.H.A., the peeling mask eliminates dead cells to unclog pores and refine the skin's texture. Over time, it helps to reduce the presence of blemishes such as blackheads. Used once or twice a week, this gel mask leaves the complexion unified and the skin's texture smoothed.

Lactic acid being a photosensitising molecule, these treatments should be used only in the evening. The application of a broad-spectrum sunscreen is strongly recommended the following morning. Before any use, perform a skin tolerance test. Apply a few drops of your treatment to the crook of your arm or the back of your hand and wait 24 hours. If you observe any skin reaction, do not use the serum on your face.