What Is Your Skin’s pH and Why Does It Matter?

Do you remember doing those high school chemistry experiments that tested the pH level of various substances? Your teacher passed out little strips of paper, and you exposed them to different kinds of liquid to see how acidic or basic they were.

If you didn’t grow up to become a scientist, you might think those tests (and those terms) would never be relevant to your life again. But if you care about your skin health, it’s worth revisiting those lessons of old.

Dermatology resident Taylor Bullock, MD, explains what pH means when it comes to your skin.

What is pH in skin?

pH stands for “potential hydrogen,” where “potential” means “power.” It refers to how acidic a substance is — in this case, your skin. Everyone’s skin has its own pH, and bringing yours into balance can go a long way toward achieving the healthy skin you’re hoping for.

pH is measured on a scale of 0 to 14, with 7, right in the middle, representing a neutral pH. The lower a substance’s pH, the more acidic it is; the higher the pH, the less acidic it is. Put simply:

• A pH below 7 is acidic.
• A pH of 7 is neutral.
• A pH above 7 is non-acidic (also known as basic or alkaline).

All kinds of things can affect the pH of your skin, including your diet, hygiene habits or which skin care products you use.

What is the best pH level for skin?

You might think that you’d want your skin to be a solid 7. Perfectly neutral, right? That’s a logical assumption, but it’s actually not the correct one.

“For adults, the skin’s normal pH is about 5.5, which is just a little bit acidic,” Dr. Bullock shares. “This acidity helps maintain the balance of the skin’s natural oils and protect it from harmful bacteria.”

The skin on your face and hands is typically more alkaline than the skin on parts of your body that aren’t exposed as often — think armpits, groin, etc.

If your skin is too acidic or too basic, how will it look?

“If your pH becomes too high or too low, that disrupts the skin’s natural microenvironment,” Dr. Bullock explains. “Your normal, healthy bacteria don’t grow as well, and the skin barrier doesn’t work as well.”

When the pH of your skin becomes too acidic or too basic, it can lead to skin issues:

• Dryness and flakiness: Too much or too little acid can strip your skin of its natural oils and dry it out.
• Acne: A disruption in the balance of your skin’s natural oils encourages bacteria to grow, which can lead to breakouts.
• Irritation: An off-balance pH can cause issues like redness, itching and inflammation.
• Sensitivity: Your skin may also be more prone to irritation, especially when it’s exposed to environmental factors like wind, cold or sun.

Disrupted skin pH is associated with chronic skin conditions like:

• Acne.
• Eczema.
• Psoriasis.
• Rosacea.

Can you test your skin’s pH level?

If you’re experiencing ongoing issues with your skin — like acne, flaking, dryness or irritation — that’s probably a good sign that something is off. Left to your own devices, though, there’s no real way to test your skin’s pH level.

At least one skin care company offers a wearable sensor that claims to be able to tell you your skin’s pH and propose a new, customized skin care regimen for you. But the best thing to do it is always to see a dermatologist, who’ll know exactly what questions to ask to help identify whether your skin’s pH is off-balance.

“Once they’ve learned more about your skin care habits, your environment and how your skin behaves, they can provide guidance about what sort of products and practices are likely to be best for you, along with what you should avoid,” Dr. Bullock states.

How to restore your skin’s pH balance

When you’re choosing skin care products, it can be tough to know what they’ll do for your pH level. But there are some helpful clues and rules of thumb:

• Trust in cleanser: Don’t wash your face with the same bar of soap that you use on your body! Bar soap usually has a higher pH than facial cleansers, so it can strip your skin of its natural oils and bacteria, disrupting the delicate pH balance. Instead, use a gentle cleanser on your face to help maintain a healthy pH.
• Read the label: “Some product labels advertise them as being ‘pH balanced,’ which is always a useful indicator,” Dr. Bullock notes. “Products that are categorized as being mild or are marketed for sensitive skin are also going to be much more pH balanced.”
• Pay attention to what your skin is telling you: Not everyone needs a mild product. “If you have oily skin, you might be able to tolerate or even need products that are a bit of a harsher wash,” Dr. Bullock says.
• Ask a professional: Why go it alone? Make an appointment with a dermatologist, who can help you figure out exactly what your skin needs and how to achieve it.