If you’re like me, you probably haven’t thought about the term “pH” since high school chemistry class. But if you want clear, radiant skin, it may be time to get science-y, stat.

Why? If your skin’s pH level is out of whack (either too acidic or too alkaline) it can lead to such skin woes as acne, dryness, rosacea, and even wrinkles, says Marisa Arredondo, founder of Phace Bioactive, a skin-care line formulated specifically around pH.

Pollution, sun, allergens, and other chemicals and particles all have a tremendous impact on skin’s pH. But so do the beauty products you’re using every day, says independent cosmetic chemist Ni’Kita Wilson. “Using a skin-care product with a higher or lower pH [than the optimal range] can take the skin longer to go back to normal, which some say can stress the skin.”

No need to start setting up beakers and pH strips in your bathroom to prevent beauty issues from popping up. Here are four things you need to know about skin-care pH:

1. Healthy skin should be slightly acidic, with a pH between 4–5.5. Your skin’s pH level is a measure of how acidic or alkaline it is. (And for a Chem 101 refresher: Zero is acid, and 14 is basic, or alkaline. Water is neutral, at 7. Anything in the 0–7 range is acidic.)

Keeping skin’s acid mantle—the thin protective barrier, made up of fatty acids and secretions from sweat and oil glands—in the optimal pH range of 4–5.5 keeps your glow going, Arredondo says.

2. Your cleanser could be throwing off your pH. Using a cleanser that’s too alkaline is one of the biggest skin-care mistakes people make, Arredondo says. And Arielle Kauvar, MD, founding director of New York Laser & Skin Care, agrees: “Products that are too alkaline (like soap detergents, i.e., sodium laurel sulfate) damage the skin’s acid mantle and make us vulnerable to pollutants and infections; bacteria thrive in an alkaline environment.” (Here are some cleaner choices and bar soaps.)

3. An alkaline state is great for your body, but not for your skin. It may seem counter-intuitive, especially if you’re familiar with the concept of alkalinity and how it’s great for your health. But you want to keep things alkaline (around 7.4) in your diet to promote healthy cell growth and inhibit disease, many experts say. These steps, plus managing stress, exercising, and getting enough sleep, all play a factor in keeping your body alkaline and healthy—and your overall health shines through in your complexion.

4. As you age, your skin naturally becomes more alkaline, Arredondo says, which is one more reason why it tends to get dry, brittle, and of course, wrinkly. (Swinging too far the other way isn’t the answer, either. There’s a reason that acid peels are in-office treatment at a certain point.)

So, to keep your skin in its pH sweet spot, it’s all about balance—not super scientific know-how. Though if you want to wear a lab coat while you moisturize, we won’t stop you. —Amy Marturana 

For more information, visit www.phacebioactive.com

(Photos: Phace Bioactive)

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