Skintegra Clarion 2% BHA čistač za lice

Why is the pH of cosmetic products important?

Do you know the pH value of the products you use? If skin care is important to you, the pH value of the cosmetic products you use should also be important to you.

In order to understand why we emphasize this topic, find out what the pH value is, how it is defined and what the pH of the skin itself is, which will help you with the correct selection and combination of products.

The acidity of the solution depends on the concentration of hydrogen ions H + , and is expressed by the physical quantity pH, which is defined as the negative decade logarithm of the concentration of H + ions. At 25 ℃, the pH value can be between 0 and 14. Acidic solutions are those whose pH is less than 7, neutral solutions have a pH value of 7, while alkaline solutions are those whose pH is greater than 7.

In the 19th century, it was discovered that the surface of the skin is acidic , and in the 20th century it was called the "acid mantle" . The pH of the skin surface varies between 4.5 and 5.5 and plays an important role in skin physiology. It is important in the regulation of the process of keratinization and desquamation, wound healing, the action of the enzymes phospholipase and glucocerebrosidase, and the protection of the skin against the colonization of pathogenic bacteria.

The pH value of the skin is affected by substances that are excreted on its surface, such as sweat, sebum and natural moisturizing factors (NMF). Likewise, the sebaceous and eccrine glands secrete acids such as amino acids, free fatty acids, lactic and butyric acid. Also, on the surface of the skin there are bacteria that produce lipases and esterases that break down triglycerides into free fatty acids, which leads to a decrease in pH, which creates unfavorable conditions for the colonization of pathogenic bacteria. 

It is important to emphasize that various external factors, such as soaps, detergents and cosmetic products, can affect the pH of the skin surface. Theirs use can cause a change in the pH of the skin, which negatively affects the function of the epidermal barrier and the microbiome of the skin. Maintaining the physiological pH of the skin is a very important task, and therefore it is necessary to pay attention to the pH value of the cosmetic products we use. 

Skintegra Amphibian facial cleansing gel texture

Facial cleansing products are an important example. Skin cleansing is a complex physico-chemical interaction of skin, surfactants (PAT) and water. Skin cleansing products must be mild and selective in order to remove dirt, sweat, sebum and fat from the skin without damaging the stratum corneum, the main protective barrier of the skin. When cleaning the skin, irritation may occur through the interaction of PAT and the structure of the stratum corneum, lipids and proteins, but the pH of the product also plays an important role in causing irritation. Soap-based cleaning products are alkaline by nature, while most cleaning products with synthetic PAT, so-called syndeti, are close to neutral pH or slightly acidic. Alkaline facial cleansing products have a significantly higher pH than naturally acidic skin. By such a drastic increase in the pH of the skin, the hydrolipidic barrier is significantly compromised, which makes the skin less able to defend itself against the proliferation of microorganisms that can cause acne and infections. Using mild non-ionic and/or amphoteric PATs and conditioning ingredients in a skin-like pH medium reduces the irritant potential of skin wash products. 

After removing surface impurities, the skin needs to compensate for the moisture lost during cleaning. Likewise, after cleansing the face, the pH of the skin is elevated and it needs to be brought back to an optimal pH of 5.5 in order to preserve the barrier function of the skin. Therefore, it is recommended to use a moisturizing essence with a balanced pH.

The pH value is important in every cosmetic product, but especially in pH-sensitive products such as chemical exfoliants. In order for AHA and BHA acids to be effective and for the difference to be visible on the skin, they should be in an acidic pH medium, ideally between 3 and 4 . 

An interesting example is vitamin C, a powerful antioxidant that prevents damage caused by solar radiation . Products with ascorbic acid should be in a medium with a pH value of 3.5, which is necessary to optimize the absorption of vitamin C, which also increases the possibility of unwanted reactions such as irritation and redness of the skin. Vitamin C derivatives in a pH neutral medium are therefore a more suitable choice for products for sensitive skin.

It should be pointed out that not all cosmetic ingredients are suitable for combining with each other , and such examples are niacinamide and AHA and BHA acids. Since acids are most often found in a medium with a pH value of 3-4, and niacinamide 5-7, it is important not to mix them so that their effects do not cancel each other out. In other words, niacinamide would raise the pH of the acids, making them less effective, and the acids cause the conversion of niacinamide to niacin, which can cause transient reddening of the skin. It is necessary to wait at least 30 minutes between the application of acids and niacinamide or to use them at different times of the day; niacinamide in the morning routine, and acids in the evening routine.

It is important to emphasize that all Skintegrina products are formulated so that the pH of the product is optimized! 

Choose wisely, because a well-adjusted pH medium of the product is the way to healthier skin.


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  2. Ananthapadmanabhan KP, Moore DJ, Subramanyan K, Misra M, Meyer F. Cleansing without compromise: the impact of cleansers on the skin barrier and the technology of mild cleansing , Dermatol Ther 17(1) (2004) 16-25.
  3. Babilas P, Knie U, Abels C. Cosmetic and dermatologic use of alpha hydroxy acids , J Dtsch Dermatol Ges 10(7) (2012) 488-491.
  4. Pullar J, Carr A, Vissers, M. The Roles of Vitamin C in Skin Health , Nutrients, 9(8) (2017) 866.
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