In this article, you will find out what the pH of the skin is all about. Among other things, we will clarify the questions of which factors influence the pH value, how you can regulate your acid-base balance, what the symptoms of a too high pH value are, and what you can look out for in skin care products.

Skin pH – Definition And Importance

The letters P and H are derived from the Latin “potential hydrogen ii” and mean something like “potential of hydrogen.” So, pH indicates the level of hydrogen ions and measures the strength of the acid and base concentration in a solution. So, pH is a measure of measuring the difference between acids and bases and their strengths.

Skin pH - Definition And Importance

Depending on the body region and other factors, the optimal pH value of human skin is between 4.1 and 5.8. It suggests that our skin is naturally slightly acidic. It is because our body’s substances, such as sebum and sweat, are also somewhat acidic. Anything below the neutral value of 7 is considered acidic, and anything above it is considered alkaline or basic.

Inner Influences

  • Age
  • Gender
  • Body region
  • Genetics
  • Hormones
  • Skin diseases (e.g., neurodermatitis, psoriasis, acne – they usually have a higher pH value)

External Influences

  • Temperature fluctuations
  • Cosmetics and skin care products
  • Washing too often or too hot
  • Environmental influences
  • The protective acid mantle

The pH Of The Skin – Symptoms Of A Disturbed Acid-Base Balance

If the pH is too high and thus out of balance, you can probably recognize it from the following symptoms

  • Dry patches of skin
  • shed
  • the feeling of tightness (especially after cleaning)
  • Fold
  • blemishes
  • itching
  • redness
  • Pale complexion

If the skin’s pH gets out of control, it reduces its resistance. As a result, the regeneration of the skin is also slowed down. The consequences are that the skin becomes more sensitive, which can also be seen from the skin’s appearance based on the above symptoms.

In contrast, healthy skin shows a radiant glow. It does not stretch and is neither dry nor oily. These signs tell you that the pH is excellent and in balance.

What Ph Value Should Care Products Have?

As already described above, the pH value of care products should be between 4.1 and 5.8 in order not to unbalance the pH value of the skin. However, the pH of our skin increases with age. Therefore, it makes sense to use products designed for mature skin. Unfortunately, these products often have a low pH value and can thus permanently reduce the increased value.

Optimum pH Of Shampoo

Shampoo should ideally have a pH of 4.4 as the scalp’s pH is between 4.4 and 5.5. If the pH value of our scalp changes, for example, by using products that are too aggressive, symptoms similar to those on the skin of the face appear: the scalp begins to itch, flake, and dry out.

Slightly acidic shampoos can regulate the pH value of the scalp again and bring balance.

pH Of Soap

Since soap has a high alkaline pH (usually between 9 and 10), it is unsuitable for facial cleansing. In the long run, alkaline products such as soap can negatively affect the pH value of our skin and even damage the skin.


If the pH value is too alkaline, the natural balance of the skin and the protective barrier is disturbed. The skin then dries out. As a result, the protective barrier can no longer provide adequate protection, and the skin becomes more susceptible to irritation and infection.