A scientific explanation

This subject has been an eye-opener and one of the most interesting studies we have worked with over the last few years in our product development: SKIN pH. Based on the knowledge we gained, we have created a new type of skincare product – which, basically, optimises skin health.

Read about our HERO pH solution 02 here and dive into the important knowledge of skin pH below.

What is pH?

pH is a numeric value that is applied to measure the acidity of a hydrous solution, skincare products and on the surface of the skin. The pH scale measures how acidic or alkaline a substance is, and the scale ranges from 0 to 14; a pH of 7 is neutral, a pH of less than 7 is acidic and a pH higher than 7 is alkaline. Balanced skin thrives with a pH value of approximately 5, meaning that the skin pH is slightly acidic. Conversely, the inner body thrives at a neutral pH value of 7.

Is your skin’s pH in balance or is it out of sync?




Why is the skin’s pH so significant?

The skin deserves the best conditions and the most significant starting point for achieving healthy skin is a stabilised pH value. The pH of the skin plays a crucial role in the skin’s condition and appearance. Changes in the pH value affect the enzyme activity and disrupt the natural cell renewal processes that are vital to the skin’s health.

The skin has a delicate protective layer on the surface; the acid mantle, which consists of sebum and sweat from the many microscopic pores in the skin. The acid mantle’s most important job is to protect the skin by maintaining an optimal balance of moisture, natural protective oils and the skin’s vital bacterial flora. At the same time, it has to protect from harmful exogenous bacteria, fungal infections, UV radiation and pollution. The acid mantle functions as an essential protective barrier and “a knight in shining armour” for the skin’s immune system.


What happens if the skin’s pH is out of sync?

If the skin’s pH is affected in a neutral, alkaline or overly acidic direction, the acid mantle is put under stress and its balance is temporarily disrupted. It can take hours until the protective barrier is stabilised and restored, and in the meantime, the skin is left vulnerable and susceptible to infection, irritation and desiccation. If this occurs on a daily basis, or multiple times a day, the acid mantle does not regenerate optimally.

As a result, the skin takes longer to restore its pH balance and remains dry, vulnerable or stressed, and this is the main reason for many skin issues.

Many different factors can affect the skin, and when something as simple as tap water pushes the skin in an alkaline direction, a lot of people will be exposed to a high pH for many hours of the day. If we include all the other factors, the acid mantle can be negatively affected over a long period, leaving the skin less resistant and more vulnerable as a result.

The time it takes for the skin to stabilise its pH depends, among other things, on the person’s skin type, age and biological sex and more.

What affects the skin's pH?

The pH of the skin is affected by various endogenous and exogenous factors. The skin’s pH value can vary according to where it is measured on the body, and many dermatological skin conditions such as different types of dermatitis will show deviations on the pH scale.

Exogenous factors

Exogenous factors that affect the pH balance:

/ Contact with water: showering and washing hands/cleansing the skin.

/ Contact with soap and detergents.

/ Use of harsh, astringent face and body products, including cosmetics.

/ Abrasive treatment with exfoliating and peeling skincare products.

/ Dirt and pollution.

/ Changes in temperature and weather.

/ Visits to the public pool.

Endogenous factors

The body’s endogenous environment: hormones, biological sex, age, genes and lifestyle can affect the skin’s pH balance.

/ Factors such as the biological sex can play a role as the pH value is often slightly lower on men’s skin than on women’s skin as men’s skin often produces more sebum.

/ Just as our age manifests itself in our skin, so, too, does the pH value to a certain degree. A new-born baby, who does not yet have a fully developed protective acid mantle, has a slightly alkaline pH and therefore extra sensitive skin. As hormones change during puberty, pregnancy and menopause, the skin’s pH can also change.

/ Healthy diet and lifestyle choices can help the skin maintain a healthy pH.

What if the skin is affected in a neutral/alkaline direction? (7 or higher)

The skin is affected to a more neutral or alkaline level by contact with water, soap and detergents, visits to the public pool, hand sanitiser or if the skin is cleansed or exfoliated. When the skin is too alkaline, it can suffer from extreme dryness or have a tight or fragile surface. Skin with a pH value of around 7 or above is at a greater risk of developing inflammation and unbalanced enzyme activity, which accelerate the skin’s ageing process and break down collagen fibres.

The skin can also have a tendency towards impurities and acne due to the lack of the skin’s moisturising and protective sebum.

What if the skin’s pH is in balance (around 5)

This is the best basis for healthy skin. A slightly acidic pH helps maintain the skin-friendly bacterial flora in the skin. These bacteria are a part of the skin’s immune system, which impedes harmful bacteria from penetrating the skin. What’s more, the skin’s natural sebum production is in balance, and the acid mantle is functioning optimally. The skin is smooth and does not feel too dry or too oily.

What if the skin is acidic? (below 4)

Acid turns the skin acidic, and skin with a pH below 4 is often hypersensitive, susceptible to infection and looks red and irritated. This skin condition is less common but can occur if the skin is treated with a harsh chemical peel or by other cosmetic chemical treatments where the skin is “stripped” of its natural protective oils. Limescale remover, acidic cleaning products or something as natural as lemon juice can also push the skin in an acidic direction.

The majority of store-bought skincare products containing chemical peeling/fruit acid can be used on the skin without any problem, but it is still important to show caution when it comes to applying acidic skincare. If the skin begins to break out in a rash more frequently or becomes more sensitive, it may be that the product is too harsh for the skin or that it is applied too often.

The essential role pH value plays in wound healing, eczema and other dermalogical skin conditions

Scientific documentation shows that a neutral to alkaline pH value can be measured in chronic wounds and areas affected by eczema. Studies show that if a wound or other dermatological disorder on the surface of the skin is stimulated to an acidic pH, the skin’s defence mechanism undergoes a better or more effective healing process than if it remains in its neutral or alkaline state. A stabilised pH value plays an essential role in wound healing as well as skin disorders and general dermatological skin diseases such as seborrheic dermatitis, psoriasis, rosacea, eczema and acne*.

We, at Karmameju would really love us to start talking a lot more about the skin’s pH in the skincare industry, as it is key to the health, general condition and appearance of our skin.

All the best /


*Links to scientific articles that emphasise the importance of a stabilised pH value on the skin.