We spent a ton of time researching the optimal pH for acne prone skin and went ahead and conducted a self-test to see how pH impacts our skin. The results of that little self assessment and extensive literature search showed that pH 6.0 is the optimal pH for products that work best on acne prone skin. This finding contradicts with some widely held views and articles just looking at the pH of our skin's surface, but acne starts below the surface, so why are we only paying attention to surface pH?
The pH of our skin shifts dramatically from the surface of the skin (typically 4.5 to 5.9) to the living skin layers of the epidermis and dermis, increasing by about two pH units over the first 100 microns of skin thickness. That means you don't have to go very deep to see a large shift in pH from the acid mantle (skin surface) closer to the living skin layers.
We didn't just rely on research when deciding on a target pH for our products. We took our products to the streets using them ourselves and requesting all our testers to try them out too. What we found after years of research is that a product with a target pH of 6.0 is less likely to cause breakouts than a product with a target pH of 5.5 or lower.
Go ahead and check out the article here to learn more.