Glow & Shine: Why the pH value is so important for beautiful skin and hair

We have probably all heard about it many times, but very few of us know exactly what it is: we are talking about the pH value. Yet it has a great significance when it comes to whether we have healthy skin or tend to have problems. But why is it like that at all?

The abbreviation "pH" stands for the Latin term "potentia Hydrogenii". Translated, it means something like "concentration of hydrogen ions". The pH value is used to measure the content of hydrogen ions in a solution. The concentration is limited to a scale from 0 (acidic) to 14 (basic). Pure water lies in the golden mean on the scale with a pH value of 7. As a general rule, a value of less than 7 is called acidic, and greater than 7 is called alkaline. Important: At a pH value lower than 2 or higher than 12, the extremes begin, which are very harmful to the skin and can lead to chemical burns. So much for the theory.

The horny layer and the protective acid mantle (consisting of sebum, sweat and horny cells) of our skin consist partly of water and therefore have their own pH value. Depending on the person and body region, the value varies, but normally lies between 4.1 and 5.8. The average value is 5.5. This means that our skin is slightly acidic - and that is a good thing. The interaction of the acid mantle with healthy bacteria forms our skin's microbiome, which fends off harmful microorganisms and other external environmental influences.

If the pH value of the skin rises into the alkaline or basic range for any reason, its natural balance is disturbed. Important lipids can no longer be built up, the skin loses water and dries out. In this state, the outer layer of skin (also called the epidermis) can no longer provide sufficient protection. This, in turn, increases the skin's susceptibility to infections or even disease flare-ups, such as with neurodermatitis or rosacea.

Normally, the skin's acid mantle is stable, but massive over-care or an unhealthy lifestyle with too much sugar, sun, stress, alcohol or nicotine can throw it out of balance. The result can be dark circles under the eyes, a sallow, sagging complexion, loss of skin elasticity, allergic reactions or even inflammation.

You should also take a look at your skin care products. The pH value is usually indicated on the packaging. Generally, the higher the pH value, the more water the product extracts from the skin and dissolves salts. This makes the skin more sensitive and susceptible. On some skin care products you can often read the term "pH-neutral". In effect, this means that the pH value of the product corresponds or harmonises with the natural pH value of the skin. The average value of 5.5 mentioned at the beginning is considered particularly tolerable. 

Even though you might not think of it at first, but in fact the pH value of the scalp is also very important - on the one hand for the scalp itself and of course for beautiful and shiny hair. The crux of the matter is: The scalp has a natural pH value that lies in the acidic range. The average value here is also 5.5. However, the majority of hair care products have an alkaline pH value. Care products with a much higher, alkaline pH value can in turn negatively change the value of our scalp. The result: it dries out and is irritated. The hair also suffers from the alkaline pH value: It causes more friction between the individual hair fibres, which promotes damage. This leads to frizz and brittle hair. 

That's why acids are THE beauty trend of the moment when it comes to hair care. Because they are actually able to rebuild fractures between the amino acids within the hair fibre and thus strengthen the hair. This is possible by optimising the pH value of hair and scalp. Acid-based care can also help to build up the hair. Apple, almond, amino or lactic acids are particularly frequently used for this purpose. Thanks to them, the hair gets more shine, is strengthened, is less prone to frizz and the colour also remains intense for longer. 

We already know the nurturing effect of acids from our daily skincare routine. But hair and scalp also benefit from them and will therefore become a beauty trend in 2022. Amino acids, for example, can penetrate deep into the hair. They accumulate in the weakened areas of the shaft and thus strengthen the hair from the inside out. Thanks to tartaric acid, conditioning substances can adhere to its surface more easily. In addition, tartaric acid helps the hair to ward off oxidative stress, such as UV radiation. 

But acids are not only found in care products. Hair styling products can also provide additional support and strength to the hair. Malic acid contained in hair serums, styling creams or anti-frizz sprays, for example, is able to rebuild fractures between amino acids within the hair fibre, strengthen the hair and prevent hair breakage.