In skin care, there are two things we’re always trying to keep balanced: oil levels and pH levels. A terrific skin toner will help manage both matters, but that’s tough to achieve because many toners that help to control oil levels might be so drying—or overly acidic—they, in turn, throw your pH levels out of whack. This brings us to the biggest question of them all: What are pH levels, and why is it important to keep them balanced? Understanding the answer will transform your skin care regimen—often, simplifying it—and the result will be calmer, happy skin day in and day out.
What is pH?
While it’s not imperative to get into the textbook-level definition here, know that pH stands for “potential hydrogen,” and it is a measurement along a spectrum of something’s acidity or basicity. Remember in high school chemistry, having to classify substances as acidic or alkaline (basic)? It’s that IRL. There is a zero to 14 scale denoting if something is acidic (low pH) or basic (high pH). The middle, seven, is neutral, and anything less than that increases in acidity to zero, whereas anything above it increases in alkalinity to 14. Different elements and organisms carry different pH levels; a neutral seven isn’t necessarily equilibrium. Skin’s own pH levels are just south of that number. In fact…
Skin’s pH Explained
Most important for this topic is the skin’s natural pH level, which, depending on the individual, is usually somewhere between five or six on the pH scale, says board-certified dermatologist Tsippora Shainhouse, MD, of SkinSafe Dermatology in Beverly Hills. She adds that some people’s natural pH might even be as low as 4.7.
Yes, that means that skin leans slightly acidic. So, while a pH level of seven is purely neutral on the spectrum itself, human skin needs to stay in a more acidic range to be balanced, and there are many things that can work against this harmony, especially when certain skin care products and environmental factors are introduced. If you let skin skew too far away from this five to six region, you risk disrupting its barrier functions. “The skin’s acid mantle, a.k.a. the skin barrier, is made up of sebum, lactic acid, and amino acids. This barrier enables the skin to retain moisture, keep out germs, damaging UV rays, and environmental pollutants, and prevent it from becoming irritated by topical chemicals and skin care products,” explains Dr. Shainhouse.
There’s no easy way to check the pH balance of your skin. But there are other, more indirect, ways to monitor it.
How to Know Your Skin’s pH is Imbalanced
If your skin is inflamed, dry, irritated, and overly sensitive, it might be suffering from a high pH, Dr. Shainhouse says. “The alkali strips the skin of its protective properties. It can lead to premature skin aging and wrinkling.”
Low skin pH—again, meaning it has gotten too acidic—manifests as redness, irritation, oiliness, or increased acne. “Many skin care products are acid-based and can help treat some acne, but overusing them can remove the protective skin barrier, leaving skin irritated and hypersensitive,” Dr. Shainhouse says. (She’s speaking about lactic acid and glycolic acid, which, while both helpful in their own right, can be easy to over-exfoliate. On the other hand, salicylic acid is more neutral and less caustic on the skin.)
