What is pH and why does it matter in skincare? Let's take a look at the different layers of skin and the roles they play:
Epidermis: This is your skin barrier. The epidermis on your face has four layers - the top layer is called the stratum corneum and is comprised of layers of skin cells and lipids. The lipids surrounding the skin cells contain cholesterol, ceramides, and fatty acids.
Laying on top of the stratum corneum is a thin film called your acid mantle, this has a pH of ~4.5-6. The acidic pH of the acid mantle is crucial for a healthy functioning skin barrier.
Your skin barrier and acid mantle work to protect your skin from bacteria, infection, pollutants, and moisture loss. A damaged skin barrier can lead to dehydrated skin, skin disorders, excess oil production, acne, and sensitivity.
Damage to your epidermis has a chain reaction which then affects your dermis - including what we're all most concerned about as we age: collagen production.
Dermis: Contains your collagen, elastin, hair follicles, oil glands, and blood vessels.
Hypodermis: Made up of fatty tissue.
pH stands for "potential of hydrogen." The pH scale is used to specify how acidic or alkaline a water-based solution is by testing the hydrogen ion (H+) activity.
Since our skin's acid mantle is slightly acidic at around 4.5-6, it is best to use skincare products close to this range so as not to disrupt it more than necessary. Using products too often that majorly disrupt the pH balance can lead to a damaged skin barrier.
The exception would be slightly acidic (pH ~3-4) chemical exfoliants such as AHA's (alpha hydroxy acids such as lactic acid) and BHA's (beta hydroxy acids such as salicylic acid). Our skin naturally neutralizes the acids and returns to it's normal pH range within about 30 minutes. These chemical exfoliants have been shown to be beneficial to the skin by speeding up cellular turnover rate, stimulating collagen and elastin production, and keeping the skin smooth and hydrated. Physical exfoliants, on the other hand, scrape off the top layer of skin and can cause micro-tears in the skin (I'm looking at you apricot and walnut scrubs).
Using products on the skin that are too acidic or alkaline can cause significant damage, and the skin has a harder time returning to equilibrium (DIY using lemon and baking soda, anyone?). During this time the skin is vulnerable to outside irritants and repeated use can lead to a damaged skin barrier and accelerated skin aging.
But essentially, anything we put on our skin, pH balanced or not, is disrupting it's equilibrium. This is why I believe less is more when it comes to skincare. Do you really need a 10-15 step skincare routine twice a day? Probably not. Choosing a few high quality, effective products (and sticking with it!) is much more productive than bombarding your skin with lots of new products.
While we have made every attempt to ensure that the information contained on this site is obtained from reliable sources, Sophia Dee Skincare is not responsible for any errors or omissions, or for the results obtained from the use of this information. All information in this site is provided "as is", with no guarantee of completeness, accuracy, timeliness or of the results obtained from the use of this information.