Why skin pH is critical for healthy skin
Skin pH levels are critical in maintaining healthy and balanced skin.
pH (short for the power of hydrogen) is a scale used to specify the acidity or basicity (alkalinity) of a solution. But what does it actually mean for something to be acidic or basic? The short answer is that acidic solutions have high concentrations of hydrogen ions and basic solutions have low concentrations of hydrogen ions. Acidic substances also tend to taste sour (e.g., lemon juice), and many basic substances tend to be slippery (e.g., soap or bleach).The pH scale ranges from 1 to 14, with lower numbers being more acidic, higher numbers being more basic, and around 7 being neutral. Healthy skin’s pH is acidic, at pH ≈4.5-5. This is significantly lower than the internal body pH (which is at ≈7.4). This difference might not seem significant at first, but a shift between one pH unit and the next can actually have a dramatic effect on biological processes. This is because pH units are logarithmic, meaning the difference between each number is 10 times in hydrogen ion concentration.
The pH scale ranges from 1 to 14
So why our skin takes the trouble to maintain this acidic pH on the skin surface? Well, it turned out that this acidic skin surface protects us against harmful microbes, such as pathogenic bacteria or fungi. Also, many critical skin enzymatic reactions have evolved to thrive in this acidic pH. Thus, if these ideal pH levels are disrupted, our skin defense and many crucial enzymatic reactions are compromised.
The harmful effects of low skin surface pH
Ceramides are a critical component of the skin barrier; when you develop a ceramide imbalance, skin barrier function is compromised. Ceramides and pH are closely related because two key ceramide-processing enzymes, beta-glucocerebrosidase, and acidic sphingomyelinase, require an acidic pH to function . Each time skin’s surface pH increases, these two ceramide-synthesizing enzymes slow down and eventually stop producing ceramides.
Unfortunately, it’s not as simple as applying more ceramides to pH-imbalanced skin. There is more at play: at ideal pH levels, good skin microflora that help support healthy skin are able to thrive. However, when pH levels are not properly managed, the skin microbiome is affected favoring the growth of pathogenic bacteria, fungi, or yeast. This disbalance can lead to skin infections and inflammation.
In addition to slowing ceramide-producing enzyme activity and throwing off microflora balance, high pH can also harm skin by activating destructive enzymes such as serine proteases. Once activated, these destructive enzymes degrade the main structures that keep your skin cells together. Serine proteases can also degrade the ceramide processing enzymes, further weakening ceramide production. It all begins to snowball from there and may result in skin barrier disruption, infection, inflammation, and trigger eczema –.
Skincare and pH
Disruptions to our skin surface pH levels happen frequently and we’re usually unaware of those occurrences. This is because when these disruptions are short-lived (such as with a shower), our skin is able to regulate and rebalance its surface pH. Every time we hop in the shower, wash our hands, or even apply cosmetics, we challenge our skin and temporarily disrupt the pH balance. Healthy skin is relatively unaffected by these pH fluctuations. However, when these disruptions are prolonged or repeated, our skin pH moves too far away from the optimal acidic pH and doesn’t have an opportunity to bounce back. These prolonged changes in skin pH greatly affect skin health and contribute to skin conditions such as dry skin, eczema, or even acne.
Every time we hop in the shower, wash our hands, or even apply cosmetics, we challenge our skin and temporarily disrupt the pH balance.
Leave-on skincare products (lotions, creams, serums) stay on your skin for several hours and can have a big impact on skin health as they can cause a prolonged shift in skin surface pH. This is why using products with optimal pH for your skin is critical, especially if you have dry or eczema-prone skin. Unfortunately, many current products on the market aren’t formulated at skin-optimal pH levels  and those that are don’t always list pH values.
Our SolutionScience has shown that maintaining the right skin surface pH levels is key to healing and maintaining healthy skin. Our products are here to help you with setting and maintaining this ideal pH level. Once that is established, your skin’s microflora and enzymatic reactions can function efficiently. However, the key takeaway here is an awareness of skin surface pH so you can make the right decisions with pH-balanced skincare products and in your approach to long-term skincare. After all, healthy skin is beautiful skin!
Our mission is to bring you products that have not only the optimal pH for your skin but also products that can maintain the optimal pH on your skin over a long time. Read more about how our products maintain skin pH at the optimal level.
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