Lactic Acid at a Glance
- Exfoliates the surface of skin
- Has hydrating properties
- Strengthens skin’s barrier
- Helps positively influence skin’s microbiome
Lactic Acid Description
Lactic acid is an alpha hydroxy acid (AHA) that can be extracted from milk but those seeking to avoid animal-derived ingredients should know: Despite such natural origins, the lactic acid used in cosmetics is typically made via non-dairy fermentation, creating a bio-identical synthetic acid that’s easier to stabilize and formulate with, plus it’s vegan. This is the type of lactic acid Paula’s Choice Skincare uses.
In a pH-correct formula (ideally a pH between 3 and 4) and in concentrations between 5 and 12%, lactic acid exfoliates on the surface of skin. It does this by breaking down the material that holds dead skin together, allowing it to shed naturally as it once did. Lactic acid also has hydrating properties (as sodium lactate, it is part of skin’s natural moisturizing factor, or NMF).
In addition to these benefits, lactic acid strengthens skin’s barrier by encouraging it to make more ceramides, a key component of healthy skin. It also strongly influences skin’s microbiome, helping to keep its first line of defense strong by positively interacting with a neuropeptide in skin’s surface known as Substance P, resulting in quick diffusion of signs skin is stressed.
Like glycolic acid (another popular AHA), it helps brighten an uneven, dull skin tone.
Lactic Acid References
International Journal of Cosmetic Science, April 2020, pages 116-126
International Journal of Dermatology, March 2019, ePublication
Clinical, Cosmetic, and Investigational Dermatology, October 2018, pages 491-497
International Journal of Dermatology, September 2018, ePublication
Molecules, April 2018, ePublication
Journal of the American Dental Association, April 2016, pages 255-263
Cutis, January 2016, pages E9-E11
Clinical, Cosmetic, and Investigational Dermatology, November 2010, pages 135-142
The Journal of Dermatology, January 2006, pages 16-22