Skin pH: What Is Normal and Why Does It Matter?
The pH of your skin is crucial for its health. It affects its protective function, its moisture balance and its defence against harmful microorganisms. Healthy skin is slightly acidic, with a pH of roughly between 4.5 and 5.5. External influences such as hard water, UV radiation and the wrong skincare products can upset this balance.
The key points at a glance:
- Normal skin pH: around 4.5 to 5.5 – slightly acidic. Studies show that the natural value is, on average, even below 5.
- pH too high: leads to dryness, a feeling of tightness and sensitivity, and weakens the skin barrier.
- pH too low: is less common and is usually caused by acid peels that are too strong. The result is irritation and redness.
- Influencing factors: age, hormones, water, environment, cleansing and skincare products – and, to a small extent, diet too.
Quick tips: Use a skin-neutral pH cleanser instead of classic soap, avoid hot water and harsh soaps, and make sure you eat a balanced diet, for example with vitamin C and omega-3 fatty acids. A stable pH ensures healthy, resilient skin.
What is the pH of the skin?
The pH value indicates how acidic or basic (alkaline) something is. The scale ranges from 0 (very acidic) through 7 (neutral) to 14 (very basic). At around 4.5 to 5.5, the surface of healthy skin is in the slightly acidic range. A large measurement study with 330 participants even concluded that the natural pH of the skin is around 4.7 on average – and that skin with a value below 5 has a better barrier, holds more moisture and flakes less.
| For comparison | Typical pH |
|---|---|
| Healthy skin surface | approx. 4.5–5.5 (around 4.7 on average) |
| Skin of newborns | higher at first, falls in the first weeks of life |
| Skin in older age | tends to be slightly higher than in younger adults |
| Tap water in Europe | usually around 7–8 |
| Classic soap | approx. 9–10 |
| Skin-neutral pH wash lotion (syndet) | approx. 5–5.5 |
The acid mantle
The acidic film on the skin is called the acid mantle. It is made up of sweat, sebum, free fatty acids and acids such as lactic acid, which the skin produces itself. This film is more than just a protective shield:
- It keeps the good skin bacteria: the natural skin flora feels at home in an acidic environment, while many pathogens find it harder.
- It helps build the barrier: the enzymes that produce the skin's lipids (ceramides) work best in the acidic range. When the pH rises, on the other hand, enzymes become active that loosen the bonds between the horny cells – the barrier becomes more permeable.
You can read how the skin barrier is structured and what happens when it loses water in Understanding the skin barrier. We explain the role skin bacteria play in Understanding the skin microbiome.
What does “pH-neutral” actually mean?
This often causes confusion. Chemically neutral is a pH of 7. For the skin, however, that would already be slightly basic. When skincare products say “pH-neutral” or, better, “skin-neutral pH”, it usually means: the product has roughly the pH of the skin, i.e. around 5.5. That is exactly what's good for cleansing.
Problems caused by an unbalanced pH
When the pH gets out of balance, the health and appearance of the skin suffer. Whether it is too high or too low makes a difference.
When the pH is too high
A pH that is too high, i.e. too alkaline, is the more common case. It weakens the skin barrier and can lead to these problems:
| Symptom | Effect |
|---|---|
| Dryness | The skin loses moisture |
| Tightness | The skin feels taut and less elastic |
| Flaking | The outer layer of skin flakes off more |
| Sensitivity | Greater irritability in response to external influences |
In addition, the skin loses some of its natural protection against germs, because some bacteria can multiply more easily in a less acidic environment.
When the pH is too low
A pH that is too low, i.e. too acidic, rarely occurs naturally. It is usually caused by acid peels that are used too often or are too strong. The consequences:
- The skin burns, turns red and is irritated.
- The skin barrier is put under strain, making the skin more sensitive.
- The natural balance of the skin flora can be thrown off.
We show you how to recognise overstressed skin in Impaired skin barrier: 5 signs.
Skin conditions and pH
A shifted pH can intensify existing skin problems:
| Skin condition | Link to pH |
|---|---|
| Atopic dermatitis | The skin's pH is often raised, which weakens the barrier even further |
| Psoriasis | An alkaline environment can put further strain on the already stressed barrier |
| Eczema | pH fluctuations can make symptoms worse |
| Acne | A disturbed skin environment can encourage blemishes |
People with sensitive skin or skin prone to irritation in particular therefore benefit from a stable pH and from skin-neutral pH or slightly acidic skincare.
What changes the pH of the skin
Physical factors
With increasing age, the skin tends to become somewhat more alkaline. Hormonal fluctuations, for example during puberty, pregnancy or the menopause, can also change the pH. Then there is your general state of health and metabolic processes, as well as the area of the body: in skin folds, such as the armpits, the value is naturally higher.
External influences
| Influencing factor | Effect on pH |
|---|---|
| Tap water | Raises the skin's pH – according to a study for up to six hours |
| Hard water | Raises the skin's pH even further and leaves limescale residue |
| Chlorinated water | Can shift the pH into the alkaline range and dry out the skin |
| UV radiation | Puts strain on the skin barrier and can change the pH |
| Air pollution | Puts strain on the skin barrier and can disturb the skin environment |
Cleansing and skincare products
You have the biggest influence yourself, through how you cleanse. Classic soaps are strongly alkaline and raise the skin's pH considerably. Healthy skin rebalances this within a few hours; sensitive or impaired skin needs longer or can barely manage it any more. Mild, skin-neutral pH wash lotions without harsh surfactants are better.
Ingredients such as parabens, silicones or synthetic colourants don't change the pH themselves, by the way. People with sensitive skin often avoid them anyway, though, because they offer no skincare benefit or can irritate. More on this in 10 ingredients sensitive skin should avoid.
Natural ingredients such as neem extract can support the skin during this phase: they soothe and help the barrier recover. The pH itself, however, is determined mainly by the formulation of a product, not by a single active ingredient.
Measuring the pH of the skin
To determine the skin's pH precisely, you need standardised conditions and special measuring devices such as those used in dermatology and in studies. For use at home, there are pH test strips. However, they only give a rough indication, because sweating, washing and creams strongly influence the result, and there are no clear instructions on how to interpret the values. So if you're unsure or have persistent skin problems, get advice from a dermatologist.
Restoring the skin's pH: here's how
With the right habits and suitable skincare, you help your skin preserve or rebuild its acidic protective mantle.
1. Cleanse gently and with a skin-neutral pH
Use a mild, skin-neutral pH cleanser morning and evening instead of classic soap, and water that isn't too hot. Our Body Wash, for example, has a skin-neutral pH and is sulphate-free. Avoid washing your hands frequently with harsh soaps – and moisturise your hands afterwards.
2. Use skincare that supports the barrier
Choose dermatologically tested skincare without harsh ingredients that suits your skin type. Our Med Care line with the active complex NEEMAVERA® supports the skin barrier and soothes irritated skin. For specific skin problems, the rich Cream forte or the Skin Balm can be helpful.
3. Stay consistent
A consistent routine is crucial for the skin to stabilise in the long term. Watch how your skin reacts and adjust your skincare if necessary.
4. Go easy on acid peels
Don't use fruit acid and other acid peels too often or too strongly – once or twice a week is usually enough.
5. Pay attention to diet and everyday life
The direct influence of diet on the skin's pH is small. But a balanced diet is good for your skin overall:
- drink enough, around 1.5 to 2 litres a day,
- include foods rich in vitamin C,
- add omega-3 fatty acids, for example from linseed oil, walnuts or fish,
- eat fewer sugary foods.
Summary
| Area | Recommended | Better to avoid |
|---|---|---|
| Cleansing | Mild, skin-neutral pH products, lukewarm water | Classic soap, harsh surfactants, hot water |
| Skincare | Dermatologically tested natural products | Irritating additives |
| Peels | In moderation, once or twice a week | Acid peels that are too frequent or too strong |
For healthy skin in the long term:
- a daily, tailored skincare routine,
- special care for skin problems,
- regularly keeping an eye on the condition of your skin.
A pH of roughly between 4.5 and 5.5 is the foundation for healthy and resilient skin. With the right skincare and mindful habits, you can maintain this balance in the long term.
Frequently asked questions
What is the pH of healthy skin?
Healthy skin is slightly acidic, with a pH of around 4.5 to 5.5. Studies show that the natural value is, on average, even around 4.7.
Why is the skin's pH important?
The acidic pH keeps the skin barrier intact, protects against germs and ensures the skin holds on to moisture. If it rises, the skin becomes drier, more sensitive and more prone to irritation.
What happens if the skin's pH is too high?
The skin becomes dry, feels tight, flakes and reacts more sensitively. The barrier becomes more permeable, and some germs can multiply more easily. A common cause is cleansing with classic soap.
How can I restore my skin's pH?
With mild, skin-neutral pH cleansing, lukewarm water, barrier-strengthening skincare and moderate use of peels. Healthy skin then usually restores its pH by itself within a few hours.