The dangers of lactic acid.

Belonging to the same family as theglycolic acid, lactic acid is part of the alpha-hydroxy acids. It is often used in peels because it has excellent keratolytic properties, meaning it removes dead cells from the surface of the epidermis.

Indeed, it dissolves the intercellular bonds. By stimulating cellular renewal, it revives dull complexions and prevents the appearance of imperfections (pimples, blackheads...). Compared to glycolic acid, lactic acid is better tolerated because it has a higher molecular weight that allows it to stay on the surface of the epidermis and be less irritating.

However, although it is suitable for all skin types, lactic acid remains a potent active ingredient that can cause side effects :

• An increase in sun sensitivity : Like all molecules in the A.H.A. family, lactic acid is a photosensitizing molecule, meaning it increases the skin's sensitivity to the sun. Therefore, applying lactic acid followed by sun exposure can lead to sunburn or skin irritations ;

• Irritations: Although it is gentler than glycolic acid, lactic acid is still an acid. It can cause mild to moderate burning sensations that are temporary. However, these effects are rare because at a concentration of 10% or less (the concentration of lactic acid allowed in cosmetics), the use of lactic acid is safe.

Like other fruit acids, lactic acid does not mix well with the sun. Indeed, it increases the skin's sensitivity to the sun's UV rays and heightens the risk of sunburn, even without direct exposure.Due to its exfoliating power, the skin is left without its natural protection against the sun's rays until the complete reformation of the horny layer, as well as the hydrolipidic film.

to apply your lactic acid treatments in the evening, especially since our cellular renewal process is more active during the night. In the days following the application, remember to protect your skin from the sun by applying a broad-spectrum sun protection .

Furthermore, to avoid any adverse effects, perform a skin tolerance test. Apply a few drops of your skincare product to the inside of your arm or the back of your hand and wait 24 hours. If your skin begins to sting and/or turn red, reduce the acid concentration and/or space out the applications. Subsequently, you can gradually increase the frequency of application and the concentration.