Grab some tea or a coffee before we delve into the world of acids.
Alpha Hydroxy Acids (HA) have been around for decades to clinically treat a range of skin conditions. They most common forms of HA’s are α-hydroxy acids (AHa), β-hydroxy acids (BHA), polyhydroxy acids (PHA), and bionic acids (PHA with an additional sugar molecule attached to the PHA structure). The most popular ones you probably have come across are glycolic acid, lactid acid and salicylic acid.
One of the most cited beneficial effects of HAs is the reported improvement of photoaged skin. These improvements have been linked to a decrease in skin roughness, discoloration, solar keratoses, overall pigmentation and also increased density of collagen and improved quality of elastic fibers. The positive antiaging effects of HA’s has lead to its ubiquitous use in cosmetic products and skin care systems. You can find these acids in concentrations of 2% to 70%. The higher concentration are usually meant for chemical peels that are generally performed by esthetician or physicians.
For this particular post, I’m going to focus on AHA’s. AHA’s include glycolic acid, lactic acid, citric acid, and kojic acid. This post I will only focus on lacitid acid and glycolic acid. Glycolic acid in particular is derived from multiple sources, including cantaloupe, pineapple and sugar cane. Meanwhile lactic acid is derived from buttermilk. Interesting tidbit, we also produce lactic acid in our body. When performing strenous exercise your you have a build up of lactic acid in the blood stream due to not enough oxygen.
Studies have shown that glycolic acid can accelerate collagen synthesis in more than one way depending on the type of skin. Another study demonstrated improved levels of hyaluronic acid in the epidermal and dermal layers of the skin, increase of epidermal thickness and collagen expression. Both lactic and glycolic acid have been reported to treat hyper pigmentation formed by post inflammation and age spots. One of the contributing factors suggested is the change in the composition of the skin from the glycolic acid. The other is theory is that glycolic acid may be suppressing melanin production. Meanwhile lactic acid has been proven to be hydrating to the skin because of its ability to be small enough to penetrate into the skin. Furthermore, AHA’s are known to increase cellular turnover rate which goes down substantially as we age.
Now the important question is, how do I incorporate AHA’s into my skin care regime? For daily use of AHA, concentration should be no more than 10% at a pH level of 3.5. Glycolic acid is recommended for oily skin while Lactic acid provides better hydration to the skin. There are a lot of great brands that sell great quality lotions and serums that contain AHA’s. One of my favorite glycolic acid serum is by Peter Roth’s called 10% Glycolic acid hydrating gel. My favorite lactic acid product is by Sunday Riley called Good Genes. Let me know your favorite products that I should try out. If you are looking for a more aggressive treatment of AHA’s you can always look into chemically peeling. I personally have never dabbled into chemcially peeling, so let me know how was your experience.
When using glycolic acid it is absolutely paramount you wear sunscreen. Studies have shown that glycolic acid can make our skin more sensitive to the sun’s UV. However, whatever you are doing I generally recommend a good sunblock every day for your face because you don’t want to undermine all the hard work you are doing to reduce the effects of aging on your skin.
Stiller, Matthew J., et al. “Topical 8% Glycolic Acid and 8% L-Lactic Acid Creams for the Treatment of Photodamaged Skin: A Double-Blind Vehicle-Controlled Clinical Trial.” Archives of Dermatology, vol. 132, no. 6, 1996., pp. 631-636doi:10.1001/archderm.1996.03890300047009.
Ditre, C. M., et al. “Effects of Alpha-Hydroxy Acids on Photoaged Skin: A Pilot Clinical, Histologic, and Ultrastructural Study.” Journal of the American Academy of Dermatology, vol. 34, no. 2 Pt 1, 1996., pp. 187.
Green B. After 30 years … the future of hydroxyacids. J Cosmet Dermatol. 2005;4(1):44–45. [PubMed]