pH measures the concentration of hydrogen ions in gram equivalents per liter and is represented as a number from 0 to 14. The pH of water is 7; this is considered neutral pH. Anything less than 7 is considered an acid and anything greater than 7 is a base. The higher the pH the stronger the base. The lower pH the stronger the acid.
The pH of your skin is actually between 4.5 and 5.5 and can vary with location on your body and several other factors. When the pH gets higher than this, it can disrupt the microbiome and lead to problems such as dryness, acne, irritation, and other inflammation.
In talking with patients, we find that the acid base chemistry in different topicals can be particularly confusing. We love using terms like AHA’s, BHA’s, and HA’s... but it is important to understand what each of these compounds do and how they affect your skin.
AHA’s (alpha hydroxy acids) and BHA’s (beta hydroxy acids) are common ingredients in both over-the-counter and medical grade skin care products.
These are mild acids usually with a pH of around 3.5 that can help with exfoliation, pigment production, redness, and acne. In studies, your skin will return to its normal pH after about an hour of application. Both of these compounds can produce irritation and photosensitivity with use. When incorporating into a skin care regimen, a good rule of thumb is low concentration and slow introduction. Don’t grab the strongest AHA you can find and apply every night! We strategically use these compounds at higher concentrations for chemical peels.
If you have any skincare concerns, give us a call to set up your appointment.
