Beyond the pH Balance:
Rethinking “pH‑Balanced” Skin Care
A clearer, science‑grounded look at a very popular claim
The phrase “pH‑balanced” appears everywhere — on cleansers, shampoos, deodorants, moisturizers, and even makeup. These products promise to “restore your skin’s natural pH” and imply that matching a specific number on the pH scale is essential for healthy, youthful skin.
As interest in natural and organic skin care has grown, so has the debate. There is quite literally a War on Natural Soap!
Many companies argue that traditional natural soaps are too alkaline and therefore harmful, while their synthetic “pH-balanced” cleansers are portrayed as the safer, more scientific choice.
However, it is worth questioning whether pH-balanced products formulated with synthetic detergents, surfactants, preservatives, and other synthetic chemicals are truly better for the health of our skin.
I’m not dismissing the importance of healthy, resilient skin. A strong, intact skin barrier absolutely matters.
What I do question is the way the skincare industry has simplified complex biology into a marketing slogan, and in the process, convinced people that a single number on a pH scale determines whether a product is good or bad for their skin.
So yes, I know I’m going against the grain by defending well-formulated natural soap in a world obsessed with “pH-balanced” cleansers.
My goal isn’t to convince you of anything. It’s to help you think critically about a concept that has been repeated so often it’s rarely questioned.
pH matters to the biology of the skin — but not in the way skin‑care marketing suggests.
What pH Actually Measures
If the last time you thought about pH was in high school chemistry, here’s a quick refresher. pH stands for “potential of hydrogen” and describes the concentration of hydrogen ions in an aqueous (water-based) solution. In simple terms, it tells us how acidic or alkaline something is.
The pH scale runs from 0 to 14. Values below 7 are acidic, values above 7 are alkaline (or basic), and 7 is neutral. Pure water sits right in the middle — and interestingly, so does human blood.
Since pH ONLY applies to water-based solutions, solids do not have a pH.
- No water means no free hydrogen ions.
- No free hydrogen ions means no pH to measure.
Skin is a solid organ. Hair is a solid fiber. Neither has a pH of its own.
For the same reason, pH does not apply to products made only with oils and butters, like facial oils, body butters, salves, or balms. Again, no water — no pH.
When people talk about “skin pH,” they’re really referring to the pH of a very thin, slightly acidic film on the surface of the skin — a mixture of sweat, sebum, shed skin cells, and helpful microbes. This tiny ecosystem is known as the acid mantle.
In other words, “skin pH” describes the chemistry of the fluid on your skin, not the skin itself.
The Acid Mantle: A Dynamic, Living Micro‑Environment
The acid mantle plays several important roles. It helps limit moisture loss, supports the skin barrier, and creates conditions that favor beneficial microorganisms while discouraging harmful ones. It also helps neutralize mild alkaline substances that come into contact with the skin.
It is a constantly changing biological system, but is often described as if it has a single ideal pH number — usually 5.5. In reality, its pH is not fixed.
It shifts throughout the day and varies across different areas of the body. Moist folds tend to be more alkaline, while drier areas tend to be more acidic. Age, hormones, menopause, diet, activity level, humidity, temperature, sweat, natural oils, hygiene habits, and even time of day all influence the pH of the acid mantle.
This variability is normal. The acid mantle is not a static number; it is a constantly changing reflection of your biology and your environment.
All of this reflects a larger truth: our skin is a dynamic organ that constantly renews itself.
Why “Ideal Skin pH” Is a Misleading Concept
Imagine you and a friend finish gardening on a warm day. Your skin is damp with sweat, your temperature is elevated, and your oil glands are more active than usual. If you both measured the pH of the fluid on your skin at that moment, your readings would almost certainly differ — and both would differ again an hour later.
And that’s just one moment. Skin pH isn’t a fixed personal trait. It’s a constantly shifting biological snapshot.
So, if skin pH is always changing, when a product claims to be “pH‑balanced,” the obvious questions become:
Balanced for which person? Which body area? What time of day? Under what conditions?
The marketing sounds scientific, but the biology tells a different story.
Healthy Skin Regulates Its Own pH
Skin is a living, adaptive organ designed to maintain its own balance.
One of the most important — and most overlooked — facts about skin biology is that healthy skin restores its acid mantle quickly. Even plain water, which typically has a pH between 6 and 8.5, temporarily disrupts the acid mantle.
All cleansers — whether true soap, syndet bars, or liquid body washes — temporarily shift the pH of the skin’s surface. Research consistently shows, however, that healthy skin naturally restores its slightly acidic environment within about one to two hours after washing.
In other words, your skin has built-in mechanisms designed to bring things back into balance.
Long‑term pH changes occur only with products that are extremely acidic or extremely alkaline, or when the skin barrier is already compromised. For people with healthy skin, a skin cleanser does not need to match the acid mantle’s pH. The skin corrects minor shifts on its own.
The Microbiome: The Missing Piece in the pH Conversation
This is where the science gets especially interesting — and where the marketing narrative really falls apart.
Your skin is home to about a trillion microorganisms: bacteria, fungi, and viruses.
Together, they form the skin microbiome, a vital part of your immune system and barrier function. This tiny ecosystem:
- thrives in a range of mildly acidic conditions
- helps maintain the acid mantle
- protects against pathogens
- regulates inflammation
- breaks down sebum into beneficial byproducts
- is resilient to small pH fluctuations
The microbiome is far more sensitive to preservatives and harsh surfactants than to small pH shifts.
Why does this matter? All water-based products labeled “pH balanced” must contain preservatives — and preservatives are specifically designed to control or destroy microorganisms.
Your skin’s microbiome is made up of microorganisms.
So while a “pH balanced” cleanser may match some ideal number on a scale, its preservatives and other formula choices can still disrupt the very ecosystem that helps maintain the acid mantle in the first place.
Ingredients Matter More Than pH
A product’s pH tells you surprisingly little about how it will actually behave on your skin. What matters far more is the chemistry of the ingredients themselves — how they interact with your natural oils, your barrier lipids, and especially your skin’s microbiome.
Look at the ingredient list on many so-called “pH-balanced” cleansers, and you’ll often find a long lineup of synthetic detergents, foam boosters, stabilizers, solvents, fragrances, and preservatives.
Each of these ingredients affects the skin in its own way, yet very few have been carefully studied for their long-term impact on the acid mantle or the microbiome.
We tend to talk about pH as if it’s the only variable that matters, but real skin biology is far more complex.
Preservatives are designed to kill microorganisms — and your microbiome is made of microorganisms. Fragrances and solvents can irritate the barrier regardless of pH. Synthetic detergents remove oils indiscriminately, taking the protective lipids along with the dirt, which can leave skin stripped even when the formula is technically “skin friendly.”
So when a product claims to be “pH balanced,” it’s worth asking a simple question: balanced compared to what — and at what cost?
A cleanser can match the acid mantle’s acidity and still contain ingredients that interfere with the very systems that naturally keep skin healthy.
The truth is, we don’t yet fully understand how many modern cosmetic ingredients interact with the acid mantle or the microbiome over time. What we do know is this: skin is a living, adaptive organ, and its health depends on far more than a single number on a pH scale.
True gentleness comes from the quality and behavior of the ingredients, not from the pH printed on the label.
Syndets vs. Natural Soap
The term syndet is a blended term made by combining the words “synthetic and detergent.” Syndets are cleansing products made with synthetic surfactants rather than true soap, regardless of whether they are sold as bars or liquids.
To be clear, all cleansers—whether natural soap or syndets—work because they contain surfactants.
Surfactants allow water and oil to mix so dirt and sebum can be rinsed away.
Soap is a natural surfactant formed through saponification. Detergents are synthetic surfactants created in a lab.
Because syndets can be easily formulated to an acidic pH, manufacturers often promote them as inherently gentler and more “skin compatible.” This has become a powerful marketing advantage in a crowded marketplace.
But again, pH alone does not determine how mild or harsh a cleanser will be. A cleanser can match the acid mantle’s pH and still disrupt lipids, irritate the barrier, or disturb the microbiome.
The Reality of Rinse-Off Products
Body cleansers are rinse-off products. They remain on wet skin for seconds or minutes, and are washed away with large amounts of water.
Tap water itself has a pH, typically between about 6.0 and 8.5, depending on location and mineral content. The moment a “pH-balanced” cleanser meets that water, its original pH is diluted and altered.
In real use, the final pH at the skin’s surface depends on the formulation, the amount used, your tap water, how long it stays on the skin, and your own skin secretions. The number on the label doesn’t survive contact with real-world conditions.
Formulation Matters More Than a Number
When people ask whether our soaps and shampoos are “pH balanced,” I understand the concern. It stems from a desire for products that are gentle and supportive of skin health — and from the widespread misconception that “mild” is defined by a low pH.
But testing the pH of solid soap presents a basic scientific limitation: pH can only be measured in water-based solutions. A finished bar of soap is mostly solid fatty acid salts, not liquid water.
That means you cannot directly measure the true pH of a dry soap bar.
To get a reading at all, you have to dissolve or wet the soap in water and measure the pH of the resulting soap solution. At that point, you are testing soapy water — not the solid bar itself — and the result will vary depending on how much soap is dissolved, how much water is used, and even the pH of the water itself.
So while pH strips can provide a rough reference, they don’t tell the full story of how a soap will behave on skin.
Cold-process soap has a higher pH because it is real soap.
When natural oils react with lye, they are transformed into soap and glycerin through a chemical reaction called saponification. This is where many people misunderstand the science.
- Soap is alkaline by nature.
- Alkaline does not mean harsh.
- Harshness comes from poor formulation — not from the chemistry of soap itself.
Gentleness comes from expertise — from understanding how formulation choices shape the final bar. Accurate oil-to-lye ratios, complete saponification, thoughtful oil selection, generous superfatting, and long curing times are what create a soap that is genuinely mild and conditioning, not a number on a pH strip.
And in the end, the most meaningful test isn’t a lab strip. It’s how your skin responds over time.
You don’t need specially engineered “pH-balanced” products to have healthy skin. You need well-formulated products made with simple, purposeful ingredients — and the confidence to let your skin do its job.
Healthy skin restores its own balance naturally.
Listen to your skin.
Trust how it feels.
That will tell you far more than a pH reading ever will.
Conclusion: pH Matters, But Not the Way You’ve Been Told
The idea that skin care products must match some ideal pH is a marketing oversimplification that ignores how skin actually works.
Yes, the acid mantle is very important.
Yes, the microbiome is essential.
Yes, extreme pH levels can damage skin.
But beyond that, the story becomes far more complex.
There is no single ideal skin pH for everyone.
There is no universal pH value that every product should match.
And there is no evidence that pH alone determines whether a cleanser is gentle or harmful.
Healthy skin doesn’t come from chasing a perfect pH. It grows out of the ongoing relationship between your skin and the products you use — their ingredients, how they behave on the skin, and how your own biology responds over time.
pH is one small piece of a much larger picture.
Your skin is not a chemistry experiment that needs constant correction. It is a living, adaptive system designed to maintain its own balance.
The more we respect that, the better our skin tends to do.
